Instruction Sheet 664-510 [English, 291 KB, 7/24/1995]

Instruction Sheet 664-510 [English, 291 KB, 7/24/1995]
S&C Remote Supervisory PMH Pad-Mounted Gear
Outdoor Distribution (14.4 kv and 25 kv)
Fusing and
Manual Switching
INSTRUCTIONS
For Operation
This publication contains instructions for operation of fuses and manual Mini-Rupter
Switches in S&C Remote Supervisory PMH Pad-Mounted Gear. For operating instructions
regarding Type PM Switch Operators or the control-equipment-group components, refer to
the applicable S&C instruction sheets.
TABLE OF CONTENTS
Section
Page Number
INTRODUCTION
Qualified Persons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
SAFETY INFORMATION
Understanding Safety-Alert Messages. . . . . . . . . . . . . . . . . . . . . 6
Following Safety Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Replacement Instructions and Labels . . . . . . . . . . . . . . . . . . . . . 6
SAFETY PRECAUTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
MANUAL SWITCHING WITH MINI-RUPTER
Operating the Mini-Rupter Switch . . . . . . . . . . . . . . . . . . . . . . . . 9
Front Barriers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
FUSING
Assembling the Fuse . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Installing the Fuse in the Mounting . . . . . . . . . . . . . . . . . . . . . . 12
Warranty Qualifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
SWITCHING WITH UNI-RUPTER
Installing and Closing the Fuse . . . . . . . . . . . . . . . . . . . . . . . . . 13
A Note on Single-Pole Switching . . . . . . . . . . . . . . . . . . . . . . . . 17
Opening and Removing the Fuse . . . . . . . . . . . . . . . . . . . . . . . . 17
RE-FUSING
How to Detect and Replace a Blown Fuse . . . . . . . . . . . . . . . . 21
Installing the Fuse in the Mounting . . . . . . . . . . . . . . . . . . . . . . 22
Supersedes Instruction Sheet 664-510 dated 3-16-92
Section
23
24
24
25
25
26
27
28
31
32
ç1995
INSTRUCTION SHEET
s
Page Number
MAINTENANCE
Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Returning Equipment to Service . . . . . . . . . . . . . . . . . . . . . . . .
Enclosure Finish . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
APPENDIX A
Dielectric Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
APPENDIX B
Ratings for S&C Mini-Rupter Switches . . . . . . . . . . . . . . . . . . .
Ratings for S&C Power Fuses with Uni-Rupter . . . . . . . . . . . .
APPENDIX C
Control Equipment Groups. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
APPENDIX D
Optional Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
APPENDIX E
Current-Limiting Fuses for Use in
S&C PMH Pad-Mounted Gear. . . . . . . . . . . . . . . . . . . . . . . . . .
S&C ELECTRIC COMPANY • Chicago
S&C ELECTRIC CANADA LTD. • Toronto
664-510
Page 1 of 33
July 24, 1995
S&C Remote Supervisory PMH Pad-Mounted Gear
Outdoor Distribution (14.4 kv and 25 kv)
Fusing and
Manual Switching
INTRODUCTION
Qualified Persons
Ç WARNING
The equipment covered by this publication must be installed, operated, and maintained by qualified persons
who are knowledgeable in the installation, operation,
and maintenance of underground electric power distribution equipment along with the associated hazards. A
qualified person is one who is trained and competent in:
• The skills and techniques necessary to distinguish
exposed live parts from non-live parts of electrical
equipment.
• The skills and techniques necessary to determine
the proper approach distances corresponding to the
voltages to which the qualified person will be
exposed.
• The proper use of the special precautionary techniques, personal protective equipment, insulating
and shielding materials, and insulated tools for
working on or near exposed energized parts of electrical equipment.
These instructions are intended only for such qualified persons. They are not intended to be a substitute
for adequate training and experience in safety procedures for this type of equipment.
Ç NOTICE
When an S&C Voltage Sensor is used to provide ac
power input for an S&C Battery Charger (Catalog
Number Suffix “-Y1,” “-Y4,” or “-Y7”), the gear must
be applied at system line-to-line voltages ranging
from 11.43 kv through 17.0 kv for 14.4-kv models, and
from 20.44 kv through 29 kv for 25-kv models. In addition, when voltage sensors are used to provide ac
power input for the battery charger, single-phase
voltage sensing (Catalog Number Suffix “-Y1,” “-Y2,”
or “-Y3”), or optional three-phase voltage sensing
(Catalog Number Suffix “-W1”), the voltage sensors
must be connected to the voltage limiter at all times.
If the voltage sensors are disconnected from
the voltage limiter while the gear is energized,
the voltage sensors will be damaged.
Ç CAUTION
The equipment in this publication must be selected
for a specific application. The application must be
within the ratings furnished for the equipment.
Ratings for this gear are listed on a ratings label on
the interior of the doors (right-hand door only for
double-door models).
664-510
Page 2 of 33
July 24, 1995
INSTRUCTION SHEET
S&C ELECTRIC COMPANY • Chicago
S&C ELECTRIC CANADA LTD. • Toronto
s
INTRODUCTION — Continued
General
• Control-equipment-group components (see Appendix
Instruction manuals regarding installation and operation
of the pad-mounted gear, switch operators, and controlequipment-group components are included in the “Installation and Operation Information Kit” provided with each
unit of S&C Remote Supervisory PMH Pad-Mounted Gear.
Wiring diagrams and a catalog dimensional drawing showing cable-locating and anchor-bolt dimensions are also
provided in the information kit. All personnel involved
with installation and operation of the gear should be thoroughly familiar with the contents of the kit.
The following instructions cover operation of fuses
and manual Mini-Rupter Switches in S&C Remote Supervisory PMH Pad-Mounted Gear. For operating instructions regarding Type PM Switch Operators or the controlequipment-group components, refer to the applicable
S&C instruction sheets.
S&C Remote Supervisory PMH Pad-Mounted Gear
permits automated switching and provides fault protection for underground distribution systems. See Figures 1,
2, and 3. This gear contains the following:
• 600-ampere S&C Mini-Rupter Switches for three-pole
live switching of three-phase source circuits.
• Type PM Switch Operators to provide power operation
of the associated Mini-Rupter Switches.
C) and interconnecting-control-wiring base spacer with
low-voltage wiring for each switch operator.
• 200- or 400-ampere hookstick-operated S&C Power
Fuses with Uni-Rupter for single-pole live switching of
single-phase or three-phase load circuits. Models available offer a choice of S&C Type SML-20 or SML-4Z
Power Fuses, S&C Fault Fiter Electronic Power Fuses,
or a variety of single-barrel current-limiting fuses.
• Penta-Latch Mechanism on doors for access control.
Mechanism provides automatic door latching and permits padlocking only when the door is latched closed.
Doors can be opened only with a pentahead socket
wrench or tool except when hexhead actuators (Catalog Number Suffix “-B1” or “-B2”) are specified.
A variety of optional features are available for S&C
Remote Supervisory PMH Pad-Mounted Gear. The catalog number stamped on the nameplate affixed to the
enclosure door is suffixed with letter-number combinations applicable to the gear furnished. Refer to Appendix
D for descriptions of the optional features.
Low-voltage compartment contains a WESDAC DART RTU
(Catalog Number Suffix “-Y1”) or mounting provisions for a usersupplied and installed RTU (Catalog Number Suffix “-Y2,” “-Y3,” or
“-Y4”)
Type PM Switch Operator for power
operation of associated Mini-Rupter
Switch
Penta-Latch Mechanism
Interconnecting-control-wiring base
spacer shields low-voltage wiring from
high voltage
Figure 1. Remote supervisory Model PMH-9 with Type PM Switch Operator and low-voltage compartment. When furnished
with the communication and control equipment group (Catalog Number Suffix “-Y1”), the WESDAC DART (Distribution Automation Remote Terminal) by Westronic, Inc. is provided in the low-voltage compartment.
INSTRUCTION SHEET
s
S&C ELECTRIC COMPANY • Chicago
S&C ELECTRIC CANADA LTD. • Toronto
664-510
Page 3 of 33
July 24, 1995
S&C Remote Supervisory PMH Pad-Mounted Gear
Outdoor Distribution (14.4 kv and 25 kv)
Fusing and
Manual Switching
INTRODUCTION — Continued
Dual-purpose front barriers guard against inadvertent
contact with live parts when in normal vertical position.
Inserted into open gap of a fuse, barrier provides isolation from bus and upper contacts
S&C Penta-Latch Mechanism provides
automatic three-point door latching—only
after actuator is secured can a padlock be
installed
Compartment-identification and
phase-identification labels
Storage rack holds up to
six SM-4 Refill Units or
three SMU-20 Fuse Units
S&C Uni-Rupter
Grappler—the S&C
fuse-handling fitting
Interphase and end barriers
Ground studs
Terminals accept a wide
variety of field assembled
cable-terminating devices
Fault Fiter Electronic
Power Fuse with Uni-Rupter
SML-20 Power Fuse
with Uni-Rupter
Figure 2. Fuse-side view of a Model PMH-9 with SML-20 Power Fuses in the right-hand compartment and Fault Fiter Electronic Power Fuses in the left-hand compartment. (This nonstandard combination of fuses is shown for comparison only.)
664-510
Page 4 of 33
July 24, 1995
INSTRUCTION SHEET
S&C ELECTRIC COMPANY • Chicago
S&C ELECTRIC CANADA LTD. • Toronto
s
INTRODUCTION — Continued
Left-hand door retainer—rotate latch upward to
open door. To secure left-hand door closed, rotate
latch downward over stop mounted on outer edge
of door
Viewing window for visible verification of switch position is
removable for phasing. To remove window, loosen wing-head
screws and lift window off alignment bolts
Main bus
Optional mounting provisions for
user-supplied fault indicators
Door holder
Ground pad on inside at bottom door stile
in each compartment, accommodates connectors for attachment of cable concentricneutral ground leads and ground studs
Ground
studs
Optional fuse-storage
feature
Circuit diagram
Interphase and end barriers
Instruction manual holder
Dual-purpose front barrier guards against inadvertent
contact with live parts when in normal vertical position.
Inserted into open gap of a switch, barrier provides isolation from bus and upper contacts
S&C Mini-Rupter Switch—manually operated
switches are furnished with a manual operating handle
which folds for storage behind the switch-operatinghub cover
Figure 3. Switch-side view of a Model PMH-9.
INSTRUCTION SHEET
s
S&C ELECTRIC COMPANY • Chicago
S&C ELECTRIC CANADA LTD. • Toronto
664-510
Page 5 of 33
July 24, 1995
S&C Remote Supervisory PMH Pad-Mounted Gear
Outdoor Distribution (14.4 kv and 25 kv)
Fusing and
Manual Switching
SAFETY INFORMATION
Understanding Safety-Alert Messages
There are several types of safety-alert messages which
may appear throughout this instruction sheet as well as
on labels affixed to the S&C Remote Supervisory PMH
Pad-Mounted Gear. Familiarize yourself with these types
of messages and the importance of the various signal
words, as explained below.
Following Safety Instructions
Ç NOTICE
Thoroughly and carefully
read this instruction sheet
before operating your
S&C Pad-Mounted Gear.
Ç DANGER
“DANGER” identifies the most serious and immediate
hazards which will likely result in serious personal
injury or death if instructions, including recommended
precautions, are not followed.
Ç WARNING
“WARNING” identifies hazards or unsafe practices
which can result in serious personal injury or death if
instructions, including recommended precautions, are
not followed.
Ç CAUTION
“CAUTION” identifies hazards or unsafe practices
which can result in minor personal injury or product or
property damage if instructions, including recommended precautions, are not followed.
If you do not understand any portion of this instruction
sheet and need assistance, contact your nearest S&C
Sales Office or S&C Authorized Distributor, or call S&C
Headquarters at (312) 338-1000, Monday through Friday
between 8:30 AM and 5:00 PM Central Standard Time. (In
Canada, call S&C Electric Canada at (416) 249-9171.)
Replacement Instructions and Labels
If you need additional copies of this instruction sheet,
contact your nearest S&C Sales Office or S&C Authorized
Distributor, or call S&C Headquarters.
It is important that any missing, damaged, or faded
labels on the equipment be replaced immediately.
Replacement labels are available by contacting your nearest S&C Sales Office, S&C Authorized Distributor, S&C
Headquarters, or S&C Canada.
Ç NOTICE
“NOTICE” identifies important procedures or
requirements that, if not followed, can result in product
or property damage if instructions are not followed.
664-510
Page 6 of 33
July 24, 1995
INSTRUCTION SHEET
S&C ELECTRIC COMPANY • Chicago
S&C ELECTRIC CANADA LTD. • Toronto
s
SAFETY PRECAUTIONS
Ç DANGER
Pad-mounted gear contains high voltage. Failure to observe the precautions
below will result in serious injury or death.
Some of these precautions may differ from company operating procedures and rules.
Where a discrepancy exists, users should follow their company’s operating procedures and
rules.
1.
2.
3.
4.
5.
6.
7.
QUALIFIED PERSONS. Access to pad-mounted
gear must be restricted only to qualified persons. See
“Qualified Persons” on page 2.
SAFETY PROCEDURES. Always follow safe operating procedures and rules.
PERSONAL PROTECTIVE EQUIPMENT. Always
use suitable protective equipment such as rubber
gloves, rubber mats, hard hats, safety glasses, and
flash clothing in accordance with safe operating procedures and rules.
SAFETY LABELS. Do not remove or obscure any of
the “CAUTION,” “WARNING,” or “DANGER” labels.
KEY INTERLOCKS.
v If optional key interlocks were furnished, they
must be in place.
v Check the operating sequence of key interlocks to
verify proper sequencing.
v After the pad-mounted gear is installed, either: (1)
destroy the extra set of keys or (2) make them accessible only to qualified persons. This will maintain the
integrity of the key-interlock scheme.
v Key interlocks are not security locks and are not
substitutes for padlocks.
OPENING DOORS. Do not force doors open. Forcing a door open can damage the latching mechanism.
If optional key interlocks are furnished, correctly
position the interlocks so the doors can be opened.
CLOSING AND LOCKING DOORS.
v Doors must be securely closed and latched, with
padlocks in place at all times unless work is being
performed inside the enclosure.
v Manual Mini-Rupter Switches have switch-operating-shaft access covers located on the sides of the
pad-mounted gear enclosure. They must be closed
and padlocked at all times unless the switches are
being operated.
v Do not close a door on a fuse in the open position.
The door will strike the fuse pull ring which will
interfere with door closing. The door may be closed if
the fuse is removed from the mounting.
8. ENERGIZED TERMINALS. Always assume that
both sets of power terminals on any Mini-Rupter
Switch or fuse are energized unless proved otherwise
by test, by visual evidence of open-circuit conditions
on both sets of terminals, or by observing that both
sets of terminals are grounded.
9. BACKFEED. Mini-Rupter Switches, switch terminals, fuses, and fuse mountings (Uni-Rupter, load-side
hinge, and terminals) may be energized by backfeed.
10. DE-ENERGIZING. Before touching any device that
is to be inspected, replaced, serviced, or repaired in
the high-voltage compartments, always disconnect
Mini-Rupter Switches, fuses, and other devices such
as voltage sensors from all power sources (including
backfeed) and control sources, test for voltage, and
properly ground.
11. TESTING. Test for voltage on both sets of power terminals of any Mini-Rupter Switch or fuse using
proper high-voltage test equipment before touching
any device that is to be inspected, replaced, serviced,
or repaired in the high-voltage compartments.
12. GROUNDING.
v Make sure that the pad-mounted gear enclosure is
properly grounded to the station or facility ground.
v After the gear has been completely disconnected
from all sources of power and tested for voltage,
install suitable grounding cables in all compartments
before touching any device that is to be inspected,
replaced, serviced, or repaired in the high-voltage
compartments.
13. SWITCH POSITION.
v Always confirm the open/close position of the
Mini-Rupter Switches by visually observing the position of the switch blades.
v Switches and switch terminals may be energized
by backfeed.
v Switches and switch terminals may be energized in
any position.
Continued
INSTRUCTION SHEET
s
S&C ELECTRIC COMPANY • Chicago
S&C ELECTRIC CANADA LTD. • Toronto
v
664-510
Page 7 of 33
July 24, 1995
S&C Remote Supervisory PMH Pad-Mounted Gear
Outdoor Distribution (14.4 kv and 25 kv)
Fusing and
Manual Switching
SAFETY PRECAUTIONS — Continued
Ç DANGER — Continued
Pad-mounted gear contains high voltage. Failure to observe the precautions
below will result in serious injury or death.
Some of these precautions may differ from company operating procedures and rules.
Where a discrepancy exists, users should follow their company’s operating procedures and
rules.
14. FUSE POSITION. Fuses and fuse mountings (UniRupter, load-side hinge, and terminals) may be energized by backfeed even when the fuse is in the fully
open position.
15. S&C GRAPPLER.
v The Grappler (Catalog Number 4423) is the S&C
fuse-handling fitting supplied with each unit equipped
for fuses.
v The Grappler improves grip, balance, and control
of fuses during handling.
v Always use the S&C Grappler attached to a suitable universal pole (1¹⁄₄ diameter) to handle barriers
and to install, remove, open, or close fuses. The universal pole must be at least 4 feet long (S&C Catalog
Number 4451R2-E, or equal) for 14.4-kv gear or at
least 6 feet long (S&C Catalog Number 4452R2-E, or
equal) for 25-kv gear.
16. MAINTAINING PROPER CLEARANCE.
v When working in the high-voltage compartments,
always maintain proper clearance from energized
components.
v When handling barriers or when installing, removing, opening, or closing fuses, always use an S&C
Grappler attached to a suitable universal pole (see 15
above).
17. DUAL-PURPOSE FRONT BARRIERS.
v Always use an S&C Grappler attached to a suitable
universal pole to handle barriers in the high-voltage
compartments.
v Do not leave dual-purpose front barriers in the
“slide-in” position for more than one week. If the barriers are left in the “slide-in” position for an extended
period of time, there is the possibility of corona discharge to the barriers. Prolonged exposure to corona
664-510
Page 8 of 33
July 24, 1995
discharge can damage the barriers and result in a
flashover, injury, and equipment damage.
v Switch Side: These barriers are intended for temporary use to isolate the blades of the Mini-Rupter
Switch from the main contacts while work is being
performed.
v Fuse Side: These barriers are intended for temporary use to isolate the fuse from the contacts of the
Uni-Rupter while work is being performed.
18. CLOSING FUSES.
Closing a fuse into a faulted circuit will cause a loud
noise, a flash of light at the Uni-Rupter contacts, and
the fuse to blow. Closing a fuse into a faulted circuit is
always a possibility. When closing a fuse, always turn
your face away then use a swift, unhesitating thrust
since the closing operation is completely operator
dependent. With Uni-Rupter, the fuse can be closed
into a fault current once or twice as specified in
Appendix B, and the Uni-Rupter will remain operable
and able to carry and interrupt rated current.
19. FUSE STORAGE AND HANDLING.
v Always store fuses in a clean, dry location.
v Never store end fittings, holders, interrupting modules, or fuses in high-voltage compartments unless
the unit is equipped with the optional fuse-storage
feature (Catalog Number Suffix “-E1,” “-E2,” or “-E3”).
v If equipped with the fuse-storage feature, do not
handle spare fuses unless dual-purpose front barriers
for switches are in their normal, suspended positions
to help avoid contact with live parts.
INSTRUCTION SHEET
S&C ELECTRIC COMPANY • Chicago
S&C ELECTRIC CANADA LTD. • Toronto
s
MANUAL SWITCHING WITH MINI-RUPTER
The following instructions are for operation of manual
Mini-Rupter Switches. For Mini-Rupter Switches operated
by Type PM Switch Operators, refer to Instruction Sheet
669-515. Complete ratings for Mini-Rupters as applied in
S&C Remote Supervisory PMH Pad-Mounted Gear are
shown in Appendix B. Before proceeding, refer to the
“DANGER” on pages 7 and 8.
Operating the Mini-Rupter Switch
1. Remove the padlock and open the switch-operatingshaft access cover. See Figure 4.
2. Remove the folding switch-operating handle from its
storage pocket behind the access cover. Unfold the
handle and slide it onto the hex switch-operating shaft.
Note the switch-position indicator which is attached
to the hex switch-operating shaft and rests against a
stop in either the open or closed position. Arrows indicate switch-open or switch-closed position.
3. Rotate the handle in the appropriate direction to open
or close the switch, and check the switch-position indicator to verify that the switch is in the desired position.
Hood shields padlock shackle
Ç WARNING
Always confirm the open/close position of the MiniRupter Switch by visually observing the position of the
switch blades.
4. Remove and fold the switch-operating handle, and
return the handle to its storage position. Then close
and padlock the access cover.
Ç CAUTION
Do not leave the switch-operating-shaft access cover
unlocked if the gear is left unattended by qualified
persons.
Hex switch-operating shaft
Folding switch-operating
handle in storage pocket
Access cover in
padlocked position
Folding switch-operating
handle in operating position
Switch-position
indicator
Access cover opened
Connection diagram
Figure 4. Switch-operating handle access.
INSTRUCTION SHEET
s
S&C ELECTRIC COMPANY • Chicago
S&C ELECTRIC CANADA LTD. • Toronto
664-510
Page 9 of 33
July 24, 1995
S&C Remote Supervisory PMH Pad-Mounted Gear
Outdoor Distribution (14.4 kv and 25 kv)
Fusing and
Manual Switching
MANUAL SWITCHING WITH MINI-RUPTER — Continued
Front Barriers
Ç WARNING
Ç DANGER
When working in the high-voltage compartments,
always maintain proper clearance from energized
components. Failure to maintain proper clearance
will result in serious injury or death.
Always use an S&C Grappler (Catalog Number 4423)
attached to a suitable universal pole (1¹⁄₄ inches in
diameter) to handle barriers and to install, remove,
open, or close fuses. The universal pole must be at least
4 feet long (S&C Catalog Number 4451R2-E, or equal)
for 14.4-kv gear or at least 6 feet long (S&C Catalog
Number 4452R2-E, or equal) for 25-kv gear.
Place the dual-purpose front barrier in the “slide-in” position whenever the Mini-Rupter Switch is open. When the
barrier is in the “slide-in” position, the switch blades are
isolated from the main contacts. This also keeps the
blades from closing if, for any reason, the Mini-Rupter
Switch is operated.
To insert the barrier in the “slide-in” position, use an
S&C Grappler attached to and in line with a suitable universal pole. Figures 5 through 7 show the suggested insertion method. The Grappler prongs are pointed upward
when lifting the front barrier.
Figure 5. Dual-purpose front barrier for switch in its normal, suspended position.
664-510
Page 10 of 33
July 24, 1995
Do not leave dual-purpose front barriers in the “slide-in”
position for more than one week. These barriers are
intended for temporary use to isolate the blades of the
Mini-Rupter Switch from the main contacts while work
is being performed. If the barriers are left in the “slidein” position for an extended period of time, there is the
possibility of corona discharge to the barriers.
Prolonged exposure to corona discharge can
damage the barriers and result in a flashover,
injury, and equipment damage.
Ç NOTICE
Before closing a Mini-Rupter Switch, remove the dualpurpose front barrier from the “slide-in” position.
Closing a switch on the barrier will block the
switch blades and result in a stalled condition.
If the Mini-Rupter Switch is inadvertently closed with
the front barrier in the “slide-in” position, it will be necessary to unblock the blades. To do this, rotate the switchoperating handle all the way to the “OPEN” position. This
will return the blades to the open position. If a poweroperated Mini-Rupter Switch is closed with the dual-purpose front barrier in the “slide-in” position, refer to “IF
OPERATOR STALLS” in Instruction Sheet 669-515.
Figure 6. Grappler being used to lift barrier. Note that door
holder is in place and adjacent door is latched closed to
reduce exposure to high voltage.
INSTRUCTION SHEET
S&C ELECTRIC COMPANY • Chicago
S&C ELECTRIC CANADA LTD. • Toronto
s
MANUAL SWITCHING WITH MINI-RUPTER — Continued
To restore the dual-purpose front barrier to the normal
suspended position, use an S&C Grappler attached to a
suitable universal pole. With the Grappler prongs pointed
upward (as shown in Figure 7), slowly and carefully withdraw the barrier so that, as it clears the “slide-in” position,
the holes in the barrier catch on the hooks of the gear.
Then lower the barrier to its normal, suspended position.
(If, for any reason, the barrier was completely removed
from the enclosure, a suggested method of placing it in its
normal, suspended position is shown in Figure 8. Note
that the barrier is supported on the Grappler prongs and
held there by engagement of the lifting ring with the Grappler cone. Place the barrier on the hooks of the gear, and
lower the barrier to its suspended position.)
Figure 7. Grappler, after lifting and pivoting the barrier, is
used to lower it into the “slide-in” position. Also shows
Grappler being used to return the barrier to its normal, suspended position.
Figure 8. Alternate method of replacing front barrier using
Grappler. Inset shows close-up of Grappler in position to
replace the barrier.
INSTRUCTION SHEET
s
S&C ELECTRIC COMPANY • Chicago
S&C ELECTRIC CANADA LTD. • Toronto
664-510
Page 11 of 33
July 24, 1995
S&C Remote Supervisory PMH Pad-Mounted Gear
Outdoor Distribution (14.4 kv and 25 kv)
Fusing and
Manual Switching
FUSING
S&C Remote Supervisory PMH Pad-Mounted Gear is furnished with S&C Fuse Mountings with Uni-Rupter that
accommodate S&C Type SML-20 Power Fuses, S&C Type
SML-4Z Power Fuses, or S&C Fault Fiter Electronic
Power Fuses. Fault Fiter Electronic Power Fuse Mountings also accommodate a variety of current-limiting fuses.
Ç WARNING
When selecting current-limiting fuses, the voltage rating
of the fuses must conform to the recommendations in
Appendix E. Failure to conform to these
recommendations can result in a flashover, injury,
and equipment damage.
Assembling the Fuse
S&C Power Fuses
Install an SMU-20 Fuse Unit into each set of end fittings,
an SM-4 Refill Unit into each holder, or a Fault Fiter Interrupting Module and Control Module into each holder, in
accordance with the instruction sheet furnished with the
fuse unit, refill unit, or interrupting module.
Installing the Fuse in the Mounting
Follow the instructions found under “Installing and Closing the Fuse” on pages 13 through 16.
Warranty Qualifications
The standard warranty contained in seller’s standard conditions of sale (as set forth in Price Sheet 150) does not
apply to S&C Remote Supervisory PMH Pad-Mounted
Gear where fuse units, fuse-unit end fittings, holders, refill
units, or switch blades of other than S&C manufacture are
used in conjunction with S&C SML Mountings. Nor does it
apply to S&C Remote Supervisory PMH Pad-Mounted
Gear where other than Fault Fiter Electronic Power
Fuses, S&C Switch Blades, or the current-limiting fuses
listed in Appendix E are used in conjunction with Fault
Fiter Electronic Power Fuse Mountings and S&C Holders
designed therefor, or when current-limiting fuses are
applied other than as set forth under “Recommended Voltage Ratings” for current-limiting fuses in Appendix E.
Current-Limiting Fuses
S&C Holders for current-limiting fuses are designed for
use in pad-mounted gear models that include mountings
for Fault Fiter Electronic Power Fuses. These holders will
accommodate the current-limiting fuses listed in Appendix E. For instructions on installing current-limiting fuses
in current-limiting fuse holders, refer to S&C Instruction
Sheet 660-500.
664-510
Page 12 of 33
July 24, 1995
INSTRUCTION SHEET
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SWITCHING WITH UNI-RUPTER
Installing and Closing the Fuse
Before proceeding with the instructions on installing and
closing the fuse,d refer to the “DANGER” on pages 7
and 8.
Ç DANGER
When working in the high-voltage compartments,
always maintain proper clearance from energized
components. Failure to maintain proper clearance
will result in serious injury or death.
Always use an S&C Grappler (Catalog Number 4423)
attached to a suitable universal pole (1¹⁄₄ inches in
diameter) to handle barriers and to install, remove,
open, or close fuses. The universal pole must be at least
4 feet long (S&C Catalog Number 4451R2-E, or equal)
for 14.4-kv gear or at least 6 feet long (S&C Catalog
Number 4452R2-E, or equal) for 25-kv gear.
Use an S&C Grappler attached to and in line with a
suitable universal polel to perform the procedures listed
below:
1. Open the appropriate fuse-compartment door and
secure it with the door holder. See Figure 9. On doubledoor models, the adjacent compartment door should
be closed and latched to minimize exposure to high
voltage.
2. If optional inner barrier panels (Catalog Number Suffix
“-G7”) are furnished, loosen the pentahead bolts and
Door holder
remove the panel.
Then remove only the dual-purpose front barrier
associated with the fuse mounting into which the fuse
will be installed. See Figure 10. Insert the barrier into
the “slide-in” position using the Grappler as illustrated
in Figure 11. Note that the barrier is supported on the
Grappler prongs and held there by engagement of the
lifting ring with the Grappler cone.
Ç WARNING
Do not leave dual-purpose front barriers in the “slide-in”
position for more than one week. These barriers are
intended for temporary use to isolate the fuse from the
contacts of the Uni-Rupter while work is being
performed. If the barriers are left in the “slide-in”
position for an extended period of time, there is the
possibility of corona discharge to the barriers.
Prolonged exposure to corona discharge can
damage the barriers and result in a flashover,
injury, and equipment damage.
d Although the operations as described in this section often refer simply to “fuses,” the procedures apply to S&C Type SML-20 and SML-4Z
Power Fuses, S&C Fault Fiter Electronic Power Fuses, and current-limiting fuses used in Fault Fiter Electronic Power Fuse Mountings with UniRupter.
l If the enclosure is furnished with an optional base spacer (or is
attached to a higher than normal mounting pad), it may be desirable, for
easier handling at the increased height, to reposition the Grappler on the
universal pole at a favorable angle.
S&C Grappler in storage
position
Storage rack for S&C SMU-20
Fuse Units or SM-4 Refill Units
Figure 9. Dual-purpose front barriers for fuses in their normal, suspended positions. Note that door holder is in place.
Figure 10. Removing or replacing dual-purpose front barrier with the S&C Grappler.
INSTRUCTION SHEET
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S&C ELECTRIC COMPANY • Chicago
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664-510
Page 13 of 33
July 24, 1995
S&C Remote Supervisory PMH Pad-Mounted Gear
Outdoor Distribution (14.4 kv and 25 kv)
Fusing and
Manual Switching
SWITCHING WITH UNI-RUPTER — Continued
3. For all fuses except 25-kv Fault Fiter Electronic
Power Fuses, install a fuse into its hinge as follows:
a. Position the Grappler cone in the fuse pull ring and
cradle the fuse in the Grappler prongs. See inset of
Figure 12.
b. Grasp the universal pole with both hands (approximately 2 feet apart), with one hand at the opposite
end of the pole from the Grappler.
c. Lift the fuse and lower it into its hinge. See Figure
12. Make sure that the fuse is securely seated in the
hinge; then disengage the Grappler from the fuse.
See Figure 13.
4. For 25-kv Fault Fiter Electronic Power Fuses,
de-energize, test, and properly ground the mounting in
accordance with safe operating procedures and rules,
and then install the fuse into its mounting by hand
using suitable protective equipment.
Ç NOTICE
Do not close a door on a fuse in the open position. The
door will strike the fuse pull ring which will
interfere with door closing. The door may be closed
if the fuse is removed from its mounting.
Ç DANGER
Keep the fuse away from the Uni-Rupter contacts when
installing the fuse into its hinge. Touching the
contacts will close the circuit which can cause a
flashover and serious injury. Always place the dualpurpose front barrier in the “slide-in” position whenever a fuse is open or is being removed from or installed
into its hinge.
Figure 11. Inserting dual-purpose front barrier into the
"slide-in" position using Grappler.
664-510
Page 14 of 33
July 24, 1995
Figure 12. Installing fuse using Grappler. Inset shows
close-up of Grappler in position to install the fuse.
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SWITCHING WITH UNI-RUPTER — Continued
5. Use the Grappler to remove the dual-purpose front barrier from the “slide-in” position. See Figure 14.
Ç DANGER
Closing a fuse into a faulted circuit will cause a
loud noise, a flash of light at the Uni-Rupter contacts, and the fuse to blow. Closing a fuse into a
faulted circuit is always a possibility. When closing a
fuse, always turn your face away then use a swift, unhesitating thrust since the closing operation is completely operator dependent. With Uni-Rupter, a fuse can
be closed into a fault current once or twice as specified
in Appendix B and the Uni-Rupter will remain operable
and able to carry and interrupt rated current.
6. With the Grappler prongs pointed downward, insert the
longer prong into the pull ring of the fuse. See inset of
Figure 15. Then with one’s face turned away, close the
fuse with a swift, unhesitating thrust. See Figure 15.
Figure 13. Fuse installed in mounting in the open position.
Remove the Grappler from the pull ring.
Ç NOTICE
After removing the Grappler from the pull ring, make
sure that complete fuse closure was attained by pushing
against the fuse with the Grappler. Failure to
completely close the fuse can result in damage to
the Uni-Rupter.
7. Use the Grappler to hang the dual-purpose front barrier in its normal, suspended position. See Figure 10.
Also install the optional inner barrier panel, if furnished.
8. Close and latch the doors and install a padlock. Pull on
the doors to verify that they are securely latched.
Figure 14. Removing dual-purpose front barrier from the
“slide-in” position using Grappler.
INSTRUCTION SHEET
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S&C ELECTRIC COMPANY • Chicago
S&C ELECTRIC CANADA LTD. • Toronto
664-510
Page 15 of 33
July 24, 1995
S&C Remote Supervisory PMH Pad-Mounted Gear
Outdoor Distribution (14.4 kv and 25 kv)
Fusing and
Manual Switching
SWITCHING WITH UNI-RUPTER — Continued
Uni-Rupter
Figure 15. Closing the fuse. Inset on right shows close-up of Grappler in position to close the fuse. Top inset shows close-up
of Uni-Rupter with the fuse fully closed.
664-510
Page 16 of 33
July 24, 1995
INSTRUCTION SHEET
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SWITCHING WITH UNI-RUPTER — Continued
Ç WARNING
A Note on Single-pole Switching
In single-pole switching of ungrounded-primary threephase transformers or banks (or single-phase transformers connected line-to-line), circuit connections or parameters may, in some cases, produce excessive overvoltages.
In particular, for the following applications above 22 kv,
single-pole switching by any means—including UniRupter—should be performed only under the conditions
stated in italics:
• Switching unloaded or lightly loaded delta-connected
or ungrounded-primary wye-wye connected threephase transformers or banks (or line-to-line connected
single-phase transformers), rated 150 kva or less threephase, or 50 kva or less single-phase—or of any kva
rating when combined with unloaded cables or
lines—where maximum system operating voltage
Opening and Removing the Fuse
Before proceeding with the instructions on opening and
removing the fuse, refer to the “DANGER” on pages 7
and 8.
exceeds 22 kv. Single-pole switching should be performed only if each phase is carrying 5% load or
more, or if the transformer or bank is temporarily
grounded at the primary neutral during switching.
• Switching loaded or unloaded ungrounded-primary
wye-delta connected three-phase transformers or
banks—alone or combined with unloaded cables or
lines—where maximum system operating voltage
exceeds 22 kv. Single-pole switching should be performed only if each phase is carrying 5% load or more
and if the lighting-load phase is always switched
open first (or switched closed last); or if the transformer or bank is temporarily grounded at the primary neutral during switching.
3. With the Grappler prongs pointed downward, insert the
longer prong into the pull ring of the fuse. See
Figure 16.
Ç DANGER
When working in the high-voltage compartments,
always maintain proper clearance from energized
components. Failure to maintain proper clearance
will result in serious injury or death.
Always use an S&C Grappler (Catalog Number 4423)
attached to a suitable universal pole (1¹⁄₄ inches in
diameter) to handle barriers and to install, remove,
open, or close fuses. The universal pole must be at least
4 feet long (S&C Catalog Number 4451R2-E, or equal)
for 14.4-kv gear or at least 6 feet long (S&C Catalog
Number 4452R2-E, or equal) for 25-kv gear.
Use an S&C Grappler attached to and in line with a
suitable universal pole to perform the procedures listed
below:
1. Open the appropriate fuse-compartment door and
secure it with the door holder. See Figure 9. On doubledoor models, the adjacent door should be closed and
latched to minimize exposure to high voltage.
2. If optional inner barrier panels (Catalog Number Suffix
“-G7”) are furnished, loosen the pentahead bolts and
remove the panel. Then remove only the dual-purpose
front barrier associated with the fuse to be opened,
using the Grappler for this purpose. See Figure 10.
Figure 16. Grappler, as positioned for opening stroke, with
longer prong inserted in the fuse pull ring.
INSTRUCTION SHEET
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S&C ELECTRIC COMPANY • Chicago
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664-510
Page 17 of 33
July 24, 1995
S&C Remote Supervisory PMH Pad-Mounted Gear
Outdoor Distribution (14.4 kv and 25 kv)
Fusing and
Manual Switching
SWITCHING WITH UNI-RUPTER — Continued
4. Pull the fuse vigorously through its full travel without
hesitation at any point. See Figure 17. A downward
force should be maintained on the universal pole
through the fuse-opening operation to counteract any
tendency the fuse may have to bounce toward the
closed position.
NOTE: The Uni-Rupter is designed to require a hard
pull to unlatch the fuse, thus reducing the possibility of
an incomplete opening operation.
5. Remove the Grappler from the fuse pull ring.
Ç DANGER
The fuse and fuse mounting (Uni-Rupter, load-side
hinge, and terminals) may be energized by backfeed
even when the fuse is in the fully open position. Always
assume that both terminals of a fuse are energized
unless proved otherwise by test, by visual evidence of
open-circuit conditions on both terminals, or by
observing that both terminals are grounded. Failure to
follow these precautions can result in serious
injury or death.
Ç NOTICE
Do not close a door on a fuse in the open position. The
door will strike the fuse pull ring which will
interfere with door closing. The door may be closed
if the fuse is removed from its mounting.
6. Place the dual-purpose front barrier associated with
the fuse to be removed in the “slide-in” position. Use
the Grappler for this, as illustrated in Figure 18. Note
that the barrier is supported on the Grappler prongs
and held there by engagement of the lifting ring with
the Grappler cone.
664-510
Page 18 of 33
July 24, 1995
Ç WARNING
Do not leave dual-purpose front barriers in the “slide-in”
position for more than one week. These barriers are
intended for temporary use to isolate the fuse from the
contacts of the Uni-Rupter while work is being
performed. If the barriers are left in the “slide-in”
position for an extended period of time, there is the
possibility of corona discharge to the barriers.
Prolonged exposure to corona discharge can
damage the barriers and result in a flashover,
injury, and equipment damage.
7. For all fuses except 25-kv Fault Fiter Electronic
Power Fuses, remove the fuse from its hinge as follows:
a. Grasp the universal pole with both hands (approximately 2 feet apart), with one hand at the opposite
end of the pole from the Grappler.
b. Position the Grappler cone in the fuse pull ring and
cradle the fuse in the Grappler prongs. See Figure
19.
c. Stand in a normal, upright position facing the universal pole. Move the pole forward until resistance
between the Grappler and the fuse is felt (approximately 2 inches). Then remove the fuse from its
hinge with a forward and upward lifting motion.
See Figure 20.
Ç DANGER
Keep the fuse away from the Uni-Rupter contacts when
removing the fuse from its hinge. Touching the
contacts will close the circuit which can cause a
flashover and serious injury. Always place the dualpurpose front barrier in the “slide-in” position whenever a fuse is open or is being removed from or installed
into its hinge.
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SWITCHING WITH UNI-RUPTER — Continued
Figure 17. Opening the fuse.
Figure 19. Grappler positioned for fuse removal.
Figure 18. Inserting dual-purpose front barrier into the
“slide-in” position using Grappler.
Figure 20. Removing fuse using the Grappler.
INSTRUCTION SHEET
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S&C ELECTRIC COMPANY • Chicago
S&C ELECTRIC CANADA LTD. • Toronto
664-510
Page 19 of 33
July 24, 1995
S&C Remote Supervisory PMH Pad-Mounted Gear
Outdoor Distribution (14.4 kv and 25 kv)
Fusing and
Manual Switching
SWITCHING WITH UNI-RUPTER — Continued
8. For 25-kv Fault Fiter Electronic Power Fuses,
de-energize, test, and properly ground the mounting in
accordance with safe operating procedures and rules,
and then remove the fuse from its mounting by hand
using suitable protective equipment.
9. Hang the dual-purpose front barrier in it’s normal, suspended position using the Grappler. See Figure 10. Also
install the optional inner barrier panel, if furnished.
Then close and latch the doors, and padlock securely.
Pull on the doors to verify that they are securely
latched.
Ç WARNING
Always store fuses in a clean, dry location. Do not store
end fittings, holders, interrupting modules, or currentlimiting fuses in high-voltage compartments unless the
unit is equipped with the optional fuse-storage feature
(Catalog Number Suffix “-E1,” “-E2,” or “-E3”).
664-510
Page 20 of 33
July 24, 1995
The optional fuse-storage feature, if furnished, can
accommodate three completely assembled spare Type
SML Fuses, two spare Fault Fiter Interrupting Modules,
one spare Fault Fiter Electronic Power Fuse Holder, or
one spare current-limiting fuse holder in each switch compartment, as applicable. The fuse-storage feature is
mounted inside the enclosure, between the interrupter
switch and the side wall of the enclosure. For storage,
orient the assembled fuses in the fuse-storage feature as
shown on the label headed “STORAGE AND HANDLING
OF SPARE FUSES” that is affixed to the inside of each
applicable switch-compartment door.
Ç DANGER
Do not handle spare fuses unless front barriers for
switches are in their normal, suspended positions to
guard against inadvertent contact with live parts.
Failure to follow this precaution can result in
serious injury or death.
INSTRUCTION SHEET
S&C ELECTRIC COMPANY • Chicago
S&C ELECTRIC CANADA LTD. • Toronto
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RE-FUSING
How to Detect and
Replace a Blown Fuse
Open the appropriate fuse-compartment door and secure
it with the door holder.
Ç WARNING
To minimize exposure to high voltage on double-door
models, close and latch the adjacent door.
Also remove the dual-purpose front barrier (using the
Grappler) or inner barrier panel, if furnished.
Ç DANGER
When working in high-voltage compartments, always
maintain proper clearance from energized components.
Failure to maintain proper clearance will result in
serious injury or death.
S&C Power Fuses
From a safe distance, observe the blown-fuse target for
the fuse type furnished (refer to Figure 21):
• SML-20 Power Fuse or Fault Fiter Electronic Power
Fuse—A red blown-fuse target projects from the top of
the SML-20 Power Fuse upper end fitting or the Fault
Fiter Holder when the fuse has operated . . . making it
easy to check fuse condition with the fuse in the closed
position. The blown-fuse target retracts within the end
fitting or holder when the blown fuse unit or interrupting module is replaced.
• SML-4Z Power Fuse—A fluorescent-orange target in
the translucent SML-4Z Holder moves to the “BLOWN”
indicator window when the fuse operates, permitting a
positive visual check of fuse condition without removing the fuse from its mounting. The target fluoresces
when illuminated.
NOTE ON HANDLING: The current-design upper end
fitting for use in SML-20 Power Fuses, and the Fault
Fiter Holder employ a free-floating blown-fuse target
which can move (by force of gravity) into the
“BLOWN” position should the fuse be inverted during
handling. Fuse condition can be verified by returning
the fuse to the upright position. If the fuse is blown, the
target will remain in the extended (projecting) position.
Remove the blown fuse from its mounting following
the instructions found under “Opening and Removing the
Fuse” on pages 17 through 20. Then follow the instructions for replacing blown SM-4 Refill Units, SMU-20 Fuse
Units, or Fault Fiter Interrupting Modules (as applicable)
that are provided with each new refill unit, fuse unit, or
interrupting module.
INSTRUCTION SHEET
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S&C ELECTRIC COMPANY • Chicago
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664-510
Page 21 of 33
July 24, 1995
S&C Remote Supervisory PMH Pad-Mounted Gear
Outdoor Distribution (14.4 kv and 25 kv)
Fusing and
Manual Switching
RE-FUSING — Continued
Current-Limiting Fuses
To find the blown fuses, remove each fuse in turn from its
mounting (the target cannot be seen while the fuse is in its
mounting), following the instructions found under “Opening and Removing the Fuse” on pages 17 through 20. Then
inspect the fuse and check for a blown-fuse target.
NOTE: Following a two- or three-phase fault at a
three-phase installation, any unblown fuses that carried
Red target projects from top of upper end
fitting when fuse has operated
the fault current should also be replaced. For instructions
on replacing current-limiting fuses in S&C Holders, refer
to S&C Instruction Sheet 660-500. S&C Holders will
accommodate the current-limiting fuses listed in Appendix E.
Installing the Fuse in the Mounting
Follow the instructions found under “Installing and Closing the Fuse” on pages 13 through 16.
Red target projects from top of
holder when fuse has operated
Fluorescent-orange
target appears in
“BLOWN” indicator
window when fuse has
operated (visible through
translucent holder)
SML-20 Power Fuse
SML-4Z Power Fuse
Fault Fiter Electronic Power Fuse
Figure 21. Blown-fuse target locations for the fuse types used in PMH models of S&C Pad-Mounted Gear.
664-510
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July 24, 1995
INSTRUCTION SHEET
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MAINTENANCEa
Components
No mechanical maintenance is required for S&C Remote
Supervisory PMH Pad-Mounted Gear. However, occasional inspection of the gear and exercising of the MiniRupter Switches is recommended. Exercising of Type PM
Switch Operators once per year in accordance with
“EXERCISING AND MAINTENANCE” in Instruction
Sheet 669-515 is also recommended to verify proper functioning of the system. In addition, inspection and cleaning—of insulators and cable terminators in particular—should be performed periodically, at intervals
based on environmental conditions.
Ç WARNING
Before cleaning, completely de-energize, test, and
ground the pad-mounted gear. Never use pressuresprayed abrasives to clean pad-mounted gear.
Pressure-sprayed abrasives will damage switch
and fuse components.
Place dual-purpose front barriers for switch and fuse
compartments into the “slide-in” position. See Figures 7
and 11. This will provide physical isolation for additional
security if it is necessary to work on the cables connected
to the Mini-Rupter Switch or fuse.
Ç DANGER
When access to high-voltage compartments is required
for inspection, service, or repairs, always observe the
precautions below. Failure to observe these precautions will result in serious injury or death.
1. Access to pad-mounted gear must be restricted only
to qualified persons. See “Qualified Persons” on
page 2.
2. Always follow safe operating procedures and rules.
3. Before touching any device, always disconnect
switches, fuses, and other devices from all power
sources (including backfeed) and control sources,
test for voltage, and properly ground.
4. Always assume that both sets of power terminals on
any switch or fuse are energized unless proved otherwise by test, by visual evidence of open-circuit
conditions on both sets of terminals, or by observing that both sets of terminals are grounded.
5. Test for voltage on both sets of power terminals of
any switch or fuse using proper high-voltage test
equipment.
6. After the gear has been completely disconnected
from all sources of power and tested for voltage,
install suitable grounding cables in all compartments.
7. For maintenance of non-S&C equipment, follow the
manufacturer’s instructions.
8. Make certain the enclosure is properly grounded to
the station or facility ground. Do not return equipment to service unless such grounds are properly
made.
NOTE: Occasionally, low-voltage components may
require maintenance. The maintenance of other lowvoltage components isolated from high-voltage compartments may be performed under the safety rules for
equipment rated 600 volts or less. If maintenance is to
be performed on devices connected to the secondary
of a voltage sensor, short-circuit the secondary connections. A separate drawing will be provided with the
replacement part explaining how to properly short-circuit the secondary connections.
a These recommendations may differ from company operating procedures and rules. Where a discrepancy exists, users should follow their company’s
operating procedures and rules.
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S&C ELECTRIC COMPANY • Chicago
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664-510
Page 23 of 33
July 24, 1995
S&C Remote Supervisory PMH Pad-Mounted Gear
Outdoor Distribution (14.4 kv and 25 kv)
Fusing and
Manual Switching
MAINTENANCE — Continued
Returning Equipment to Service
Enclosure Finish
When returning the equipment to service, the following
procedures should be observed:
1. Make sure that switch and fuse grounding means are
removed and that the dual-purpose front barriers are
removed from the “slide-in” position before closing the
associated Mini-Rupter Switch or power fuses.
2. Make certain that the Mini-Rupter Switches are in the
correct positions (open or closed) as dictated by system circumstances.
3. Close each door permitting access to high voltage.
Make sure that the associated Penta-Latch Mechanisms
are securely latched and padlocked before energizing
the circuit or operating any switching device.
4. For proper setting of Type PM Switch Operators, refer
to “FINAL CHECKS BEFORE WALKING AWAY” in
Instruction Sheet 669-515.
5. For proper setting of the components furnished with
the communication and control equipment group (Catalog Number Suffix “-Y1”), refer to S&C Instruction
Sheet 660-505.
6. Padlock all doors and switch-operating-shaft access
covers before leaving the installation site, even
momentarily. Observe this procedure even in those
cases where the gear is accessible only to qualified persons.
The responsibility for ensuring that a finish protects the
enclosure lies with both the manufacturer and the user.
S&C Remote Supervisory PMH Pad-Mounted Gear is finished with the S&C Ultradur™ Finishing System, which
provides lasting protection for the enclosure. To retain
this protection, the user should take periodic corrective
action as follows:
1. Touch up any penetration of the finish to bare
metal—such as scratches and abrasions due to shipping or vandalism—to maintain the original integrity.
S&C touch-up finish and primer are available in aerosol
spray cans—order by Catalog Number: 9999-058 for
olive green finish, 9999-080 for light gray finish, and
9999-061 for red-oxide primer. No other finish or
primer is approved. The area to be touched up should
be cleaned to remove all oil and grease. Sand the area,
removing any traces of rust that may be present, and
make sure all edges are feathered before applying
primer.
2. Provide an occasional simple washdown—such as an
automobile would be given—to remove surface contaminants. Use any ordinary mild household detergent
solution.
In those cases where the enclosure must be refinished
by the user before the finish has weathered—for example,
to match other equipment—a special precaution must be
taken. The entire surface must be sanded to provide a
tooth to bond the new coat to the unusually tough and
smooth S&C Ultradur Finish.
664-510
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July 24, 1995
INSTRUCTION SHEET
S&C ELECTRIC COMPANY • Chicago
S&C ELECTRIC CANADA LTD. • Toronto
s
APPENDIX A
Dielectric Testing
When high-voltage dielectric tests are to be performed on
S&C Remote Supervisory PMH Pad-Mounted Gear, special
precautions should be taken to prevent damage to the
voltage sensor(s) and voltage limiter. Refer to S&C
Instruction Sheet 591-500.
APPENDIX B
Ratings for S&C Mini-Rupter Switches
Complete ratings for Mini-Rupters as applied in S&C
Remote Supervisory PMH Pad-Mounted Gear are shown
in the table below. In addition to the load-dropping ratings
shown, Mini-Rupter is capable of interrupting transformer
magnetizing currents associated with the applicable
loads, as well as line-charging and cable-charging currents
typical for distribution systems of these voltage ratings.
For applications on systems rated higher than 7.2 kv and
involving load current with high harmonic content (such
as rectifier load currents), refer to the nearest S&C Sales
Office. The two-time duty-cycle fault-closing ratings
shown for Mini-Rupters define the ability to close the
Mini-Rupter twice against a three-phase fault with asymmetrical current in at least one phase equal to the rated
value, with the switch remaining operable and able to
carry and interrupt rated current.
RATINGS FOR S&C MINI-RUPTER SWITCHES
Kv
Amperes, Rms
Live Switching
Nom.
Max
14.4
17.0
25
29
BIL
Cont.
Load Splitting
(Parallel or
Loop Switching)
Load
Dropping
Duty-Cycle
Fault-Closing,
Two-Time (Asym.)
Momentary
(Asym.)
1-Second
(Sym.)
95
600
600
600
22 400
22 400
14 000
125
600
600
400
22 400
22 400
14 000
14,000 amperes rms symmetrical, 35,000 amperes peak.
INSTRUCTION SHEET
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S&C ELECTRIC COMPANY • Chicago
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664-510
Page 25 of 33
July 24, 1995
S&C Remote Supervisory PMH Pad-Mounted Gear
Outdoor Distribution (14.4 kv and 25 kv)
Fusing and
Manual Switching
APPENDIX B — Continued
Ratings for S&C Power Fuses with
Uni-Rupter
Complete ratings and capabilities of S&C Power Fuses
with Uni-Rupter as applied in S&C Remote Supervisory
PMH Pad-Mounted Gear are shown in the table below.
Uni-Rupter is also capable of carrying and interrupting
load currents up to and including the emergency peakload capabilities of the associated SML Power Fuses, or
up to 400 amperes at 14.4 kv and 200 amperes at 25 kv
when used with Fault Fiter Electronic Power Fuses. In
addition to the load-dropping capabilities shown, UniRupter is capable of interrupting transformer magnetizing
currents associated with the applicable loads, as well as
line-charging and cable-charging currents typical for distribution systems of these voltage ratings. The duty-cycle
fault-closing capabilities shown for S&C Power Fuses
with Uni-Rupter represent the fault-closing capabilities of
the fuse with Uni-Rupter when the fuse is closed with a
purposeful thrust without hesitation. Following the specified number of such closings (one or two), Uni-Rupter will
remain operable and able to carry and interrupt rated
current.
RATINGS AND CAPABILITIES FOR S&C POWER FUSES WITH UNI-RUPTER
Ratings
Live Switching Capabilities, Amperes, Rms
Kv
Fuse Type
Nom.
Max
14.4
17.0
25
27
14.4
17.0
25
27
14.4
17.0
25
29
Amperes, Rms
Load
Dropping
Duty-Cycle Fault-Closing
(Asym.)
Load Splitting
(Parallel or
Loop Switching)
One-Time
Two-Time
BIL
Max
Interrupting
(Sym.)
95
200E or
200K
14 000
200
200
22 400
13 000
125
200E or
200K
12 500
200
200
20 000
13 000
95
200E
12 500
200
200
20 000
13 000
125
200E
12 500f
200
200
20 000
13 000
95
400
14 000
400
400
22 400
13 000
125
200
12 500
200
200
20 000
13 000
SML-20
SML-4Z
Fault Fiter
f Applicable to solidly grounded-neutral systems only, with fuses con-
nected by single-conductor, concentric-neutral-type cable to a transformer or transformers. Rating is 9,400 amperes rms symmetrical for all
other applications.
664-510
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INSTRUCTION SHEET
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APPENDIX C
CONTROL EQUIPMENT GROUPS
Suffix
Added to
Pad-Mounted Gear
Catalog Number
Item
Communication and Control Equipment Group12—includes WESDAC DART (in low-voltage compartment); battery charger;
battery packs; voltage sensor for power input to battery charger and for single-phase voltage sensing; and current sensors for
three-phase current sensing on each power-operated switch
Switch-Control Equipment Groups for use with RTU by
others1234—includes provisions for mounting of user-supplied and
installed RTU, transceiver, etc. in low-voltage compartment; current
sensors (5-ampere ac output) for three-phase current sensing on each
power-operated switch; voltage sensor (user-selectable 5-volts ac or
69-volts ac output) for single-phase voltage sensing (except suffix “Y4”); with power for the switch operators supplied by
Switch-Control Equipment Groups for use without
RTU347—includes provisions in low-voltage compartment for connection of switch operators to user’s wiring; with power for the switch
operators supplied by
1 The S&C Voltage Sensor is mounted on the center phase at the jawcontact side of the switch in Compartment 2 (Compartment 1 of PMH-3
and PMH-5 Models).
2 Current sensors must not be installed on unshielded cables or on
cables where the insulation is exposed but ungrounded (for example,
where dielectric tape or heat-shrink tubing is used). These sensors are
intended for application at ground potential and may be damaged by the
voltage gradient between the cable insulation and ground.
3 The low-voltage compartment is not available on models with four
switch operators.
External control power—user-supplied 24-volt dc
source
-Y2
External control power—user-supplied 120-volt ac
source to an S&C Battery Charger and battery packs5
-Y3
Internal control power—S&C-supplied (voltage sensor)
20 volt-ampere source to an S&C Battery Charger and
battery packs56
-Y4
External control power—user-supplied 120-volt ac
source to an S&C Ac Power Supply (furnished) to
develop control power input to the switch operators
-Y5
External control power—user-supplied 120-volt ac
source to an S&C Battery Charger and battery packs
-Y6
Internal control power—S&C-supplied (voltage sensor)
20 volt-ampere source to an S&C Battery Charger and
battery packs1
-Y7
4 When this option is specified, the connectors from each switch operator for connection to user’s wiring are located in the low-voltage compartment. For models with four switch operators, these connectors are
located in the switch operator that is mounted on Compartment 3.
5 The battery charger and battery packs furnished with this option are
not intended to provide power to user-supplied and installed equipment.
6 Voltage sensing is not available with this option.
7 Current and voltage sensing are not included and cannot be provided.
INSTRUCTION SHEET
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S&C ELECTRIC COMPANY • Chicago
S&C ELECTRIC CANADA LTD. • Toronto
-Y1
664-510
Page 27 of 33
July 24, 1995
S&C Remote Supervisory PMH Pad-Mounted Gear
Outdoor Distribution (14.4 kv and 25 kv)
Fusing and
Manual Switching
APPENDIX D
OPTIONAL FEATURES
Suffix
Added to
Pad-Mounted Gear
Catalog Number
Item
Light Gray Outdoor Ultradur Finish instead of olive green
Stainless-Steel Enclosure1
Hexhead Actuator for use in lieu of pentahead actuator on all PentaLatch Mechanisms
-A2
With olive green finish
-A10
With light gray finish
-A12
For use except when option suffix “-F2” is specified
-B1a
For use when option suffix “-F2” is specified
-B2a
Key Interlocks to prevent paralleling of switches in Compartments 1 and 2
-C1
Key Interlocks to prevent opening fuse-compartment doors unless all switches are locked open
-C3
Key Interlocks. Combines functions of options “-C1” and “-C3” above
-C4
Fuse-Storage Feature for three spare fuse assemblies per
compartment2
Located in Compartment 1
-E1
Located in Compartment 2
-E2
Located in Compartments 1 and 2
-E3
Mounting Provisions for a Fault Indicator in each switch compartment
Without viewing window in door
-F1
Note: Accommodates three-phase indicator with single-phase sensors
With viewing window in door
Inner Barrier Panels—a panel inside the enclosure door for each compartment, secured by recessed pentahead bolt(s)34
1 When this optional feature is specified, the entire exterior of the
enclosure, including switch operator enclosures and low-voltage compartment, is fabricated from 11-gauge Type 304 stainless steel.
2 Fuse assemblies (fuse holders or fuse units with end fittings) are not
included. For units equipped with Fault Fiter Electronic Power Fuse
Mountings, only two spare Fault Fiter Interrupting Modules, one spare
Fault Fiter Electronic Power Fuse Holder, or one spare current-limiting
fuse holder can be accommodated in each compartment.
-F2a
-G7
3 Where the National Electrical Safety Code (ANSI Standard C2)
applies, this optional feature may be included to meet the requirements of
Section 381G.
4 Meets REA’s requirements for “dead-front.”
a When optional feature “-B1,” “-B2,” or “-F2” is ordered for use with a
stainless-steel enclosure, suffix “-B11” is specified instead of “-B1,” “-B12”
instead of “-B2,” or “-F12” instead of “-F2.”
Continued
664-510
Page 28 of 33
July 24, 1995
v
INSTRUCTION SHEET
S&C ELECTRIC COMPANY • Chicago
S&C ELECTRIC CANADA LTD. • Toronto
s
APPENDIX D — Continued
OPTIONAL FEATURES—Continued
Suffix
Added to
Pad-Mounted Gear
Catalog Number
Item
Carbon steel
Base Spacer, compartmented to match enclosure, increases cabletermination height1
Stainless steel
Carbon steel
Base Spacer, noncompartmented, increases cable-termination
height1
Stainless steel
6 inches
-K1
12 inches
-K2
18 inches
-K3
24 inches
-K4
6 inches
-K11
12 inches
-K12
18 inches
-K13
24 inches
-K14
6 inches
-K7
12 inches
-K8
18 inches
-K9
24 inches
-K10
6 inches
-K17
12 inches
-K18
18 inches
-K19
24 inches
-K20
Switch- and Bus-Terminal Adapters—for connection of two cables (through 750 kc mil) per terminal2
-M1
Note: Space limitations prevent use of these adapters where surge arresters are to be installed
Cable Guides, one at each terminal23
1 Remote supervisory pad-mounted gear includes a 6-inch interconnecting-control-wiring base spacer that accommodates wiring from switch
operators to low-voltage compartment and also provides a corresponding
increase in cable-termination space. Additional base spacers are specified
accordingly.
In switch and bus compartments. For conductor sizes
No. 2 through 1000 kc mil
-M2
In fuse compartments. For conductor sizes No. 2
through 4/0
-M3
2 When optional features “-M1” and “-M2” are both specified, only one
cable guide is provided at each switch terminal.
3 These devices extend below the base of the unit. A cable pit or
optional base spacer that provides a 6-inch or greater increase in cabletermination height is required.
Continued
INSTRUCTION SHEET
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S&C ELECTRIC COMPANY • Chicago
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664-510
Page 29 of 33
July 24, 1995
S&C Remote Supervisory PMH Pad-Mounted Gear
Outdoor Distribution (14.4 kv and 25 kv)
Fusing and
Manual Switching
APPENDIX D — Continued
OPTIONAL FEATURES—Continued
Suffix
Added to
Pad-Mounted Gear
Catalog Number
Item
Polymer-Housed Metal-Oxide Surge Arresters,1 base-mounted, at switch terminals and bus terminals in Compartments 1 and 2 (removed for shipment)
9 kv
-N6a
10 kv
-N7a
12 kv
-N8
15 kv
-N9
18 kv
-N10f
9 kv, 10 kv, or 9/10 kv
-P3
15 kv
-P4
18 kv
-P5f
1200-bps modem6
Transceiver with remote
maintenance module8
-T2d
4800-bps data interface7
Transceiver with remote
maintenance module8
-T4d
9600-bps data interface7
Transceiver with remote
maintenance module8
-T6d
1200-bps modem6
Transceiver with remote
maintenance module8
-T12h
4800-bps data interface7
Transceiver with remote
maintenance module8
-T14h
9600-bps data interface7
Transceiver with remote
maintenance module8
-T16h
Mounting Provisions for Base-Mounted Surge Arresters,2 at switch terminals and bus terminals in
Compartments 1 and 2
900-Mhz Microwave Data Systems, Inc. Transceiver (Model
MDS-2310)345
400-Mhz Microwave Data Systems, Inc. Transceiver (Model
MDS-4310)3459
For
RTU
Communication Processor Module (CPM) for WESDAC DART—provides for emulation of a wide variety of commonly
used communication protocols. (Refer to the nearest S&C Sales Office for complete list)3
Three-Phase Voltage Sensing using S&C Voltage Sensors0
1 Surge arresters are base-mounted only (without isolators).
2 These provisions accommodate Ohio Brass Type PDV (metal oxide),
McGraw-Edison Type AZL19C (metal oxide), General Electric Tranquell®
(metal oxide), or McGraw-Edison Type ES (silicon carbide) distributionclass surge arresters. Surge arresters must be base-mounted only (without isolators).
-P1a
12 kv
-V1
-W1
8 Provides loopback and diagnostic capabilities including over-the-air
diagnostics and control functions such as remote display and adjustment
of transceiver power, frequency, and deviation settings.
9 Programmable within the 406-Mhz to 430-Mhz sub-band. For other
sub-bands within the 390-Mhz to 470-Mhz frequency range, contact the
nearest S&C Sales Office.
3 Only available for models specified with the communication and control equipment group (suffix “-Y1”).
0 Not available with switch-control equipment group suffixes “-Y4”
through “-Y7.”
4 Includes surge protector. Antenna, antenna support, and coaxial feedline are to be provided by others. Propagation study, frequency selection,
and FCC license application are also to be provided by others.
a Not applicable to 25-kv models.
5 Channel bandwidth is 12.5 Khz.
6 Bell 202/CCITT V.23 compatible, 1200-bps asynchronous modem is
included with the WESDAC DART.
f Not applicable to 14.4-kv models.
d Only
for use in conjunction with Microwave Data Systems’
MDS-1000HS or MDS-2100 master station.
h Only for use in conjunction with Microwave Data Systems’ MDS-4100
master station.
7 Included in transceiver—permits direct digital transmission of data.
The WESDAC DART includes RS-232 data port.
664-510
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July 24, 1995
INSTRUCTION SHEET
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APPENDIX D — Continued
ACCESSORIES
Item
Catalog Number
Grounding Jumpers, set of three, with eye-type clamps for installation with a standard shotgun
clamp stick
Shotgun Clamp Sticks for installation of grounding jumpers and for use with voltage testers
3´ cable length
4210
6´5¹⁄₂˝ length
9933-150
8´5¹⁄₂˝ length
9933-151
For grounding jumpers
Storage Bag, heavy canvas
For shotgun clamp stick
9933-149
6´6˝ length
9933-152
8´6˝ length
9933-153
Voltage Tester with audio and visual signals, includes voltage tester, batteries, adapter for shotgun clamp sticks, and storage
case1
9931-072
Current Sensors, set of three—split core, rated 600/5 amperes for application in conjunction with manually operated switches for
monitoring load currents—for conductors of up to 3¹⁄₂-inch diameter2
TA-2224
Orderwire Module and Telephone Handset for MDS Transceiver—permits connection of telephone handset to transceiver for
voice communication with master-station radio3
9931-313
Programmer/Test Set for MDS Transceiver—permits programming of transceiver operating parameters (e.g., transmit and
receive frequencies, etc.) and review of performance parameters (e.g., transmit-power output, receive signal-strength, etc.).
Transceiver must include remote maintenance module
9931-301
Maintenance Cable—for use in configuring DART RTU and
optional communication processor module (if specified). Connects communication port of user-supplied personal computer
to DART maintenance port or CPM maintenance port4
For personal computers having 25-pin serial communication
port
TA-2247
For personal computers having 9-pin serial communication
port
TA-2248
Test Cable—for use in testing functioning of remote supervisory pad-mounted gear by means of suitable user-supplied
protocol test software. Connects communication port of usersupplied personal computer to DART communication port or
CPM communication port4
For personal computers having 25-pin serial communication
port
TA-2249
For personal computers having 9-pin serial communication
port
TA-2250
For Communication and Control
Equipment Group
Suffix “-Y1”
RD-3601
Suffix “-Y2”
RD-3602
Suffix “-Y3”
RD-3603
Suffix “-Y4”
RD-3604
Suffix “-Y5”
RD-3605
Suffix “-Y6”
RD-3606
Detailed Hardware Manual—includes schematic diagrams,
circuit-board layouts, parts lists, bench-check procedures,
and operating descriptions for the switch control and battery
charger, as applicable
For Switch-Control Equipment
Groups for use with RTU by
others
For Switch-Control Equipment
Groups for use without RTU
Suffix “-Y7”
RD-3607
DART Configuration Manual—includes DART Configuration System, data files, and documentation
RD-3581
CPM Configuration Manual—includes basic version of ConfigPro Configuration System,5 data files, and documentation. Specify
protocol emulation project number
RD-3689-B
Pentahead Socket, for ¹⁄₂-inch drive
9931-074
1 For ultimate users other than electric utilities, also specify a shotgun
clamp stick of the appropriate length.
3 Only for use in conjunction with Microwave Data Systems’
2 Current sensors must not be installed on unshielded cables or on
4 A Black Box® Corp. DB-9 RS-232 Protector Part Number SP-361A-R2
cables where the insulation is exposed but ungrounded (for example,
where dielectric tape or heat-shrink tubing is used). These sensors are
intended for application at ground potential and may be damaged by the
voltage gradient between the cable insulation and ground.
is included with the maintenance and test cables to protect the DART
from damage due to electrostatic or cable capacitance discharge.
MDS-1000HSµ, MDS-2100, or MDS-4100 master station.
5 For availability of extended and developers versions of ConfigPro,
contact the nearest S&C Sales Office.
INSTRUCTION SHEET
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S&C ELECTRIC COMPANY • Chicago
S&C ELECTRIC CANADA LTD. • Toronto
664-510
Page 31 of 33
July 24, 1995
S&C Remote Supervisory PMH Pad-Mounted Gear
Fusing and
Manual Switching
Outdoor Distribution (14.4 kv and 25 kv)
APPENDIX E
Current-Limiting Fuses for Use in
S&C PMH Pad-Mounted Gear
Types Accommodated and Adapters Required
S&C Holders for current-limiting fuses are designed for
use in pad-mounted gear models that include mountings
for Fault Fiter Electronic Power Fuses. In PMH PadMounted Gear, these holders will accommodate the
single-barrel current-limiting fuses listed in the table
below when the fuses are equipped with 5/8 -inch diameter
mounting studs at both ends. Depending on the length and
diameter of the current-limiting fuse to be used, adapters
may be required in order to fit the fuse in the holder.
Adapters, when required, are furnished with the S&C
Holder and are signified by a suffix to the catalog number
of the holder. For instructions on installing current-limiting fuses in S&C Holders, refer to S&C Instruction Sheet
660-500.
CURRENT-LIMITING FUSES—Types Accommodated and S&C Holders Required
For use in
PMH Models
Rated, Kv
Current-Limiting Fuse1
Manufacturer
Catalog Number4
Type
Max, Kv
Max Amperes, Rms
B
8.3
30—112
3142-A1
Q
8.3
8.3
15.5
15.5
15.5
6—30
40—100
6—30
40—50
65—100
3142-A3
3142-A1
3142-A2
3142-A1
3142
McGraw-Edison
NX®
8.3
8.3
15.5
15.5
1.5C—40C
50C—100C
1.5C—40C
50C—100C
3142-A3
3142-A1
3142-A2
3142
RTE® ELX
8.3
15.5
3—50
3—50
3142-A3
3142-A2
Westinghouse
CX
8.3
15.5
3.5C—40C
4C—40C
3142-A3
3142-A2
Combined
Technologies, Inc.
X Limiter™
8.3
8.3
15.5
15.5
12—40
50—140
12—40
50—100
3142-A3
3142-A1
3142-A2
3142
B
15.5
22
30—100
25—65
3143R1-A1
3143R1-A1
Q
15.5
15.5
6—30
40—100
3143R1-A3
3143R1-A1
McGraw-Edison
NX®
15.5
15.5
23
1.5C—40C
50C—100C
6C—40C
3143R1-A3
3143R1-A1
3143R1-A3
RTE® ELX
15.5
23
3—50
3—40
3143R1-A3
3143R1-A3
Kearney
14.4
S&C Holder3
Rating2
Cooper Power Systems
Kearney
Cooper Power Systems
25
CX
15.5
4C—40C
3143R1-A3
CXN
15.5
45C—60C
3143R1-A1
X Limiter™
15.5
15.5
23
12—40
50—100
12—40
3143R1-A3
3143R1-A1
3143R1-A3
Westinghouse
Combined
Technologies, Inc.
1 The single-barrel current-limiting fuses listed in this table are to be
3 S&C Holders for use in 14.4-kv models of PMH Pad-Mounted Gear are
purchased from the appropriate current-limiting fuse manufacturer.
rated 14.4 kv nominal, 17.0 kv maximum, and 200 amperes maximum.
S&C Holders for use in 25-kv models of PMH Pad-Mounted Gear are rated
25 kv nominal, 29 kv maximum, and 200 amperes maximum.
2 The maximum voltage and maximum ampere ratings listed in this
table apply when the corresponding current-limiting fuse is used. Consult the appropriate current-limiting fuse manufacturer for complete fuse
ratings.
664-510
Page 32 of 33
July 24, 1995
4 Includes adapters when required.
INSTRUCTION SHEET
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APPENDIX E — Continued
Recommended Voltage Ratings
• Protection of single-phase transformers serving single-
In general, current-limiting fuses should have a maximum
voltage rating equal to, but not greater than 140% of, the
system line-to-line voltage since, for most applications,
the fuses can be exposed to full system line-to-line voltage
in clearing faults. Although there may be economic or
space-saving incentives for using current-limiting fuses
with voltage ratings “appropriate for system line-toground voltage” (i.e., fuses with a voltage rating lower
than line-to-line voltage but greater than or equal to maximum system line-to-ground voltage), S&C can only recommend such use in the following applications:
phase loads.
• Protection of three-phase lateral circuits fed by singleconductor shielded cable (provided each transformer
on that lateral is individually fused so that the currentlimiting fuse serving the lateral will not be required to
clear secondary faults).
• Protection of single-phase lateral circuits fed by singleconductor shielded cable where the load is line-toground connected.
INSTRUCTION SHEET
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S&C ELECTRIC COMPANY • Chicago
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664-510
Page 33 of 33
July 24, 1995
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