Request

Ensure that this Instruction Manual is delivered to the end users and the maintenance manager.

1 JEP0-IL9370-B

－

Safety section

－

This Safety section should be read before starting any work on the relay.

Be sure to read the instruction manuals and other related documents prior to commencing any work on the relay in order to maintain them in a safe condition.

Be sure to be familiar with the knowledge, safety information and all caution items of the product prior to use.

CAUTION

Caution means that failure to observe safety information, incorrect use, or improper use may endanger personnel and equipment and cause personnel injury or physical damage.

I tems as classified to the caution may become to occur more sever results according to the circumstance. Therefore, all items described in the safety section are important and to be respected without fail.

CAUTION

1. Items concerning transportation

(1) Be sure the equipment to be kept in normal direction

(2) Avoid the bumps, shock, and vibration, otherwise the product performance /life might be unfavorably affected.

2. Items concerning storage

(1) Environment shall be below, otherwise the product performance/life might be unfavorably affected.

-Ambient temperature: -20 ℃～ +60 ℃ (with no condensation nor freezing)

-Relative humidity: 30~80% average of a day

-Altitude: Less than 2000m

-Avoid applying unusual shock, vibration or leaning or magnetic field

-Not expose to harmful smoke, gas, salty air, water, vapor, dust, powder, explosive material or wind, rain.

3. Items concerning mounting/wiring work

(1) Mounting and wiring work should be done correctly.

Otherwise, damage, burning or erroneous operation might occur.

(2) Screw terminal should be tightened securely.

Otherwise, damage and burning might occur.

Tightened torque of screw shall be as below table

Material Size Standard torque

1.10N

・ m

Steel M3.5

(11.2kgf

・ cm)

Brass M4

0.961N

・ m

(9.8kgf

・ cm)

Permissible range

0.932

(9.5

～

～ 1.27N

12.9kgf

・

・ m cm)

0.824

～ 1.11N

・ m

(8.4

～

11.3kgf

・ cm)

Application

Terminals of back side

Type MZT Secondary terminal(k, ℓ )

(3) Grounding should be as done correctly in case it is required.

Otherwise, electric shock, damage, burning or erroneous operation might occur.

(4) Wiring should be done without mistake especially observing the correct polarity.

Otherwise, damage, burning or erroneous operation might occur.

(5) Wiring should be done without mistake especially observing the phase ordering.

Otherwise, damage, or erroneous operation might occur.

(6) Auxiliary power source, measuring transformer and power source which have enough capacity for correct operation of product should be used.

Otherwise, an erroneous operation might occur.

(7) Be sure to restore the front cover, terminal cover, protection cover, etc to the original position, which have been removed during the mounting/ wiring work.

Otherwise, electrical shock might occur at the time of checking.

(8) Connection should be done correctly using designated and right connectors.

Otherwise, damage or burning might occur.

4. Concerning equipment operation and settings

(1) Operational condition should be as below.

Otherwise, the product performance/life might be unfavorably affected.

-Deviation of auxiliary power: within +10%~-15% of rated voltage

-Deviation of frequency: within ±5% of rated frequency

2 JEP0-IL9370

-Ambient temperature: 0 ℃～ +40 ℃ (-20 ℃～ +50 ℃ is permissible during couples of hour per day, with no condensation nor freezing)

-Relative humidity: 30~80% average of a day

-Altitude: Less than 2000m

-Avoid to be exposed to unusual shock, vibration, leaning or magnetic field

-Not expose to harmful smoke, gas, salty air, water, vapor, dust, powder, explosive material, wind or rain.

(2) Qualified personnel may work on or operate this product, otherwise, the product performance/life might be unfavorably affected and/or burning or erroneous operation might occur.

(3) Be sure to read and understand the instruction manuals and other related documents prior to commencing operation and maintenance work on the product. Otherwise, electrical shock, injury, damage, or erroneous operation might occur.

(4) While energizing product, be sure not to remove any unit or parts without permissible one. Otherwise, damage, or erroneous operation might occur.

(5) While energizing product, be sure to make short circuit of current transformer secondary circuits before setting change or drawing out the sub unit. Otherwise, secondary circuit of live current transformer might be opened and damage or burning might occur due to the high level voltage.

(6) While energizing product, be sure to open trip lock terminal before setting change or drawing out the internal unit of product. Otherwise, erroneous operation might occur.

(7) Be sure to use the product within rated voltage and current.

Otherwise, damage or erroneous might occur.

5. Items concerning maintenance and checking

(1) Be sure that only qualified personnel might work on or operate this product.

Otherwise, electrical shock, injury, damage, or erroneous operation might occur.

(2) Be sure to read and understand the instruction manuals and other related documents prior to commencing operation and maintenance work on the product. Otherwise, electrical shock, injury, damage, or erroneous operation might occur.

(3) In case of replacing the parts, be sure to use the ones of same type, rating and specifications, etc.

If impossible to use above parts, be sure to contact the sales office or distributor nearest you.

Otherwise, damage or burning might occur.

(4) Testing shall be done with the following conditions.

-Ambient temperature: 20 ℃ ±10 ℃

-Relative humidity: Less than 90%

-Magnetic field: Less than 80A/m

-Atmospheric pressure: 86~106×103 Pa

-Installation angle: Normal direction±2°

-Deviation of frequency: within ±1% of nominal frequency

-Wave form(in case of AC): Distortion factor less than 2%

(Distortion factor=100%×effective value of harmonics/effective value of fundamental)

-Ripple (in case of DC): Ripple factor less than 3%

(Ripple factor=100%×(max-min)/average of DC)

(5) Deviation of auxiliary power: within ±2% of nominal voltage

(6) Be sure not to inject the voltage or current beyond the overload immunity.

Otherwise, damage or burning might occur.

(7) Be careful not to touch the energized parts.

Otherwise, the electric shock might occur.

(8) While energizing product, be sure not to clean up the product . Only wiping a stain on the front cover of product with a damp waste might be allowable. (Be sure to wring hardly the water out of the waste.)

6. Items concerning modification and/or repair work

Be sure to ask any modification and/ or repair work for product to the sales office or distributor nearest you.

Unless otherwise, any incidents occurred with modification or repair works (including software) done by any other entity than MITSUBIHI ELECTRIC CORPORATION shall be out of scope on warranty covered by MITSUBISHI

ELECTRIC CORPORATION.

7. Items concerning disposal

Particular regulations within the country of operation shall be applied to the disposal.

3 JEP0-IL9370

－

Guarantee

－

１． Guarantee period

The guarantee period of this product should be one year after delivery, unless otherwise specified by both parties.

２． Scope of guarantee

When any fault or defect is detected during the period of guarantee and such fault or defect is proved to be caused apparently at the responsibility of MITSUBISHI ELECTRIC CORPORATION, the defective unit concerned will be repaired or replaced by a substitute with free of charge. However, the fee for our engineer dispatching to site has to be covered by the user. Also, site retesting or trial operation caused along with replacing the defect units should be out of scope of our responsibilities. It is to be acknowledged that the following faults and defects should be out of this guarantee.

① When the faults or defects are resulted from the use of the equipment at the range exceeding the condition/environment requirements stated in the catalogue and manual.

② When the faults or defects are resulted from the reason concerning without our products.

③ When the faults or defects are resulted from the modification or repair carried out by any other entity than MITSUBISHI

ELECTRIC CORPORATION.

④ When the faults or defects are resulted from a phenomenon which can not be predicted with the science and technology put into practical use at the time of purchase or contract.

⑤ In case of integrating our products into your equipment, when damages can be hedged by the proper function or structure in the possession of your equipment which should be completed according to the concept of the de fact standard of industry.

⑥ In case of that the faults or defects are resulted from un-proper application being out of instruction of MITSUBISHI

ELECTRIC CORPORATION.

⑦ In case that the faults or defects are resulted from force majeure such a fire or abnormal voltage and as an act of God such as natural calamity or disaster.

３． Exclusion of loss in opportunity and secondary loss from warranty liability

Regardless of the gratis warranty term, MITSUBISHI ELECTRIC CORPORATION shall not be liable for compensation of damages caused by any cause found not be the responsibility of MITSUBISHI ELECTRIC CORPORATION, loss in opportunity, lost profits incurred to the user by failures of MITSUBISHI ELECTRIC CORPORATION products, special damages and secondary damages whether foreseeable or not, compensation for accidents, and compensation for damages to products other than MITSUBISHI ELECTRIC CORPORATION products and other tasks

４． Applications of products

① The user is requested to confirm the standards, the regulations and the restrictions which should be applied, in case of utilizing products described in this catalogue and another one in combination.

Also, the user is requested to confirm the suitability of our products to your applied system or equipment or apparatus by yourself. MITSUBISHI ELECTRIC CORPORATION shall not be liable for any suitability of our products to your utilization.

② This MITSUBISHI ELECTRIC CORPORATION products described in the catalogue have been designed and manufactured for application in general industries, etc. Thus, application in which the life or an asset could be affected, such as medical system for life-sustaining, in nuclear power plants, power plants, aerospace, and transportation devices(automobile, train, ship, etc )shall be excluded from the application. In addition to above, application in which the life or an asset could be affected by potentially chemical contamination or electrical interference and also in which the circumstances and condition are not mentioned in this catalogue shall be excluded. Note even if the user wants to use for these applications with user’s responsibility, the user to be requested to approve the specification of MITSUBISHI ELECTRIC CORPORATION products and to contact to the technical section of MITSUBISHI ELECTRIC CORPORATION prior to such applications. If the user applies MITSUBISHI ELECTRIC CORPORATION products to such applications without any contact to our technical section, MITSUBISHI ELECTRIC CORPORATION shall not be liable for any items and not be insured, independently from mentioned in this clause.

③ In using MITSUBISHI ELECTRIC CORPORATION product, the working conditions shall be that the application will not lead to a major accident even if any problem or fault occur, and that backup or duplicate system built in externally which should be decided depend on the importance of facility, are recommended.

④ The application examples given in this catalogue are reference only and you are requested to confirm function and precaution for equipment and apparatus and then, use our products

⑤ The user is requested to understand and to respect completely all warning and caution items so that unexpected damages of the user or the third party arising out of un-correct application of our products would not be resulted.

５． Onerous repair term after discontinuation of product

① MITSUBISHI ELECTRIC CORPORATION shall accept onerous product repairs for 7(seven) years after production is terminated. (However, please consider the replacement of products being in operation during 15 years from ex-work.)

② Product supply (including repair parts) is not available after production is discontinued.

６． Changes in product specification

The specification given in the catalogue, manuals or technical documents are subject to change without prior to notice.

７． Scope of service

The technical service fee such as engineer dispatching fee is excluded in the price of our products. Please contact to our agents if you have such a requirement.

4 JEP0-IL9370

MDG-A1 Series Directional Ground Relay [Standard: JIS C 4609]

Features

1.

A digital type relay corresponding ZVT, which has high accuracy and stable operating characteristics.

2.

High sensibility and wide setting range.

3.

High reliability by the self-monitoring function

The rely monitors control circuit, electric circuit and program data at all times, which are indicated by the

LED “RUN”. (The LED “RUN” lights up in the normal condition and goes out in the abnormal condition.)

4.

Enriched measurement and display functions

It is available to measure and display the input voltage, current and phase. The settings are also can be displayed.

5.

Fault record function

It can record and save the last 2 fault data including zero-phase voltage and zero-phase current and phase. So can assist with fault analysis.

6.

Standardization of the model <all specification are covered by a single model>

The relay is compatible with each specification by item setting switch changing. (50/60 Hz switching, compatibility and switching with combined, phase characteristics 45°/10° switching, output contact reset system:

Self reset/self-holding switching)

7.

High vibration and impulse resisting performance

The use of a filter circuit allows the relay to operate without the effect of higher harmonics on the distorted wave input, and this relay is also resisting to electromagnetic interference and noise and noise surge.

8.

Forced operation is available by a test button.

9.

Not need outside auxiliary power supply

The auxiliary power supply can be supplied by inside circuit of relay.

10.

20 relays can be connected from one relay with Vo expansion terminals.

5 JEP0-IL9370

1. Rating and Specifications

Type Name MDG-A1V-R MDG-A1V-RD

Element

Style No.

Protection

Measure

Frequency

092PGA 511PGA

Directional earth-fault element(MZT,MPD correspondence ※２ )×１

Zero-phase current／Zero-phase voltage／Phase

50／60Hz（Changeover）

Rating

Setting

※１

Zero-phase Current

Zero-phase Voltage

0.2A (MZT type ZCT primary)

7V｛MPD type ZVT secondary｝

AC100／110V(90～120V) Auxiliary Power Supply

Zero-phase Current (I

0

Operation Settings

)

Zero-phase Voltage (V

0

)

Operation Settings

Operation Time

0.1-0.2-0.4-0.6-0.8-1.0A (MZT type ZCT primary Conversion)

V

0

(complete earth fault) ＝ Lock-2.5-5-7.5-10%

｛When 6.6kV complete earth fault 100% V

0

primary = 3810V,

MPD-2 or MPD-3 type ZVT secondary = 7V｝

Instantaneous-0.2-0.3-0.4-0.5-0.6-0.7-0.8-0.9-1.0s

Frequency ：50Hz(SW1-ON)/60Hz(SW1-OFF) changeover

Max. sensitivity angle：Lead 10 ﾟ(SW2-ON)／45 ﾟ(SW2-OFF) changeover

Using Condition

Range

Zero-phase Real Time

Update

Current

Fault Record Range

Combined ZVT ：MPD-1,2(SW3-ON)／MPD-3(SW3-OFF) changeover

Output contact ：Self hold(SW4-ON)／Auto reset(SW4-OFF) changeover

0.05～1.5A

Approx. 200ms

0.05～1.5A

Measure

Zero-phase

Voltage

Real Time

Range

Update

Fault Record Range

Display

Phase

Real Time

Range

Update

1.0～12.0%

Approx.200ms

1.0～100%

0～359 ﾟ (V

0 standard, I

0

leg display)

Approx. 200ms

Fault Record Range

Self Monitoring

Operation Display

Numerical Display

0～359 ﾟ (V

0 standard, I

0

leg display)

The LED “ RUN ” (green) lights up in normal relay condition.

The display turns from black into orange color as the relay is put in operation. (Manual resetting type)

SW. No Indication function

０ V

0

Measure(%) ：1.0～12.0(0.1 step)

１ I

0

Measure(A) ：0.05～0.1(0.01 step),0.1～1.5(0.1 step)

２ Phase Measure(ﾟ) ：0～359(V

0 standard,I

0

lag display)

３ V

0

, I

0

Pickup ：U.－I.

４ V

0

Settings(%) ：Lo, 2.5～10

５ I

0

Settings(A) ：0.1～1.0

６ T Settings(s) ：Inst., 0.2～1.0

７ Use condition ：Condition display

８ Fault record V

0

(Newest) ：1.0～100%

９ Fault record I

0

(Newest) ：0.05～1.5(A)

Ａ Fault record Phase(Newest) ：0～359(ﾟ) (V

0 standard,I

0

lag)

Ｂ Fault record V

0

(Last time) ：1.0～100%

Ｃ Fault record I

0

(Last time) ：0.05～1.5(A)

Ｄ Fault record Phase(Last time)：0～359(ﾟ) (V

0 standard,I

0

lag)

Ｅ Fault record reset：In holding 5s, reset with O.K. displayed.

6 JEP0-IL9370

Number of relay connection Max. 20 relays can be connected through V

0

extension terminals (M-N)

Configuration ２ａ

Output

Contact Capacity

Forced Operation

Closed circuit：AC110V 10A(Power factor=0.5) DC220V 10A(L/R＝0s)

DC110V 15A(L/R＝0s)

Opened circuit: AC110V 5A(Power factor=0.5)

AC220V 1A(Power factor=0.5) DC110V 0.2A(L/R＝40ms)

Executed by pressing the TEST switch located panel.

Power Consumption VA

Mass

Case

Normal ：Approx. 4.0VA, Operating：Approx. 7.0VA

Approx. 1.0kg

Compact cylindrical fixed type

(R type)

Color：N1.5

Approx. 1.1kg

Compact cylindrical draw-out type

(RD type)

Color：N1.5

Cover Open-close type Color：Transparent

Applicable Standard JIS C 4609－

1990

※1 “Lock” means that to let this element not to operate.

※2 It is necessary to combine the MZT type ZCT and MPD type ZVT with MDG-A1 relay.

Don’t combine other types with this relay please.

7 JEP0-IL9370

2. Phase Characteristics

Guaranteed conditions Guaranteed performance

Rating frequency

Ambient temperature：20℃

Auxiliary voltage：Rated voltage

Operation time settings：0.2s

Zero-phase current setting：0.1A

Zero-phase voltage settings：2.5%

Zero-phase current input：

Setting value × 1000% (1.0A)

Zero-phase voltage input：

Setting value × 150% (143V)

Io operating area at Max. sensitivity angle.

（V

0

standard）

Phase setting

Lag

Lead

Max. sensitivity angle

45°

45°±20°

135°±20°

Max. sensitivity angle

10°

80°＋5°

－30°

100°＋30°

－10°

Max .sensitivity angle 45 °

(For non-earthing)

0 °

Lead ←

V

０ → Lag

25 °

90 °

Operation area 65 °

90 °

0.2 0.4 0.6 0.8 1.0A

115 °

155 °

Non operation area

180 °

90 °

Max .sensitivity angle 10 °

(For preacher earthing)

0 °

V

０ Lead ← → Lag

Operation area

130 °

50 °

85 °

90 °

0.2 0.4 0.6 0.8 1.0A

Non operation area

180 °

8 JEP0-IL9370

3. Internal Connection

3.1 ＭＤＧ－Ａ１Ｖ－Ｒ

Y1

V

0 in

Y2

V

0

level judgment

Direction judgment

Z1

I

0 in

Z2

I

0

level judgment

P1

Auxiliary power supply

P2

Power supply

Continuously monitoring

Power circuit monitoring

3.2 ＭＤＧ－Ａ１Ｖ－ＲＤ

※CT short when the subunit drew out

Y1

V

0 in

Y2

V

0

level judgment

Direction judment

Z1

I

0 in ※

Z2

I

0 level judgment

P1

Auxiliary power supply

P2

Power supply

Continuously monitoring

Power circuit monitoring

Fig. 3-1 Internal Connection Diagram

M

V

0

Output contact

N

Operation status display

RUN display

X0

Output contact

X0

X1

Output contact X1 a11

Output contact a12 a21

Output contact a22

E

M

V

0

Out

N

Operation display

RUN display

X0

Output contact

X0

X1

Output contact X1 a11

Output contact a12 a21

Output contact a22

E

9 JEP0-IL9370

4. Construction

LED for numerical display

By switch setting, the following Operation is available.

●

V

0 measurement and display

Residual V

0

or test input: 1.0～12.0%

(realtime values and fault records)

●

I

0 measurement and display

Residual I

0 or test input: 0.05～1.50 A (ZCT primary)

(realtime values and fault records)

●

Phase measurement and display

Phase: 0～359°（I

0 based on V

O

）

(realtime values and fault records)

ＭＥＬＰＲＯ

－A

ＭＩＴＳＵＢＩＳＨＩ

RUN

TEST

0 V

7

※

ITEM SETTING

8

1 I

0

MEASURE (A) 9

2 PHASE MEASURE (ﾟ) A

FAULT

-REC.

V

0

(%)

I

0

(A)

(LAT.) PHASE(ﾟ)

INDICATOR SELECT

3 4 5

3 PICKUP

4 V

0

SETTING(%)

5 I

0

SETTING(A)

6 T SETTING(s)

B

C

D

FAULT

-REC.

(BEF.)

FAULT-REC.IS

V

0

(%)

I

0

(A)

PHASE(ﾟ)

RESET IN 5s OR MORE

0

1

IND.

2

OFF

D

C

B

6

7

8

A

9

2

1

3 4

0

V

0

NO

SETTING

SETTING

No 整定値

※

0 LOCK

1 2.5%

2 5%

3 7.5%

4 10%

0 0.1A

1 0.2A

2 0.4A

3 0.6A

4 0.8A

5 1.0A

2

1

3 4 5

0

I

0

NO

SETTING

SETTNG

2

1

3 4 5

6

7

0 8

NO

SETTING

9

TIME(T)SETTNG

0 INST 8 0.9s

1 0.2s 9 1.0s

2 0.3s

3 0.4s

4 0.5s

5 0.6s

6 0.7s

7 0.8s

ON

1 2 3 4

OFF

ITEM SETTING

1

ON

OFF

ON

2

OFF

ON

3

OFF

ON

4

OFF

FRECUENCY

M.S,A

ZVT TYPE

OUTPUT

CONTACT

50Hz

60Hz

LEAD 10ﾟ

LEAD 45ﾟ

MPD-2

MPD-3

SELF HOLD

AUTO RESET

SYSTEM VOLTAGE READING OF SETTNG/MEASURE VALUE

6.6kV

3.3kV

×1

×2

OP.

Ｉ ＞

D I R E C T I O N A L G R O U N D R E L A Y

Ｍ Ｄ Ｇ － Ａ １ Ｖ － Ｒ

STYLE 092PGA

RATING V

0

=7V(MPD SECONDARY)

I

0

=0.2A(MZT PRIMARY) f=50/60Hz

DON’T TOUCH THE SCREW

(FOR INTERNAL FIXATION)

MITSUBISHI ELECTRIC CORPORATION

AUX.V

ZCT,ZVT

SERIAL

YEAR

JIS C 4609

AC100/110V

MZT TYPE，MPD TYPE

LEVER OPERATION

･INDICATOR AND

OPERATION RESET

･OPERATION LOCK

MADE IN JAPAN

●

V

0

/I

0 pickup display

“U” and “I” light up at each picked up.

●

Settings display

●

Operating conditions display

The operating condition settings are displayed sequentially at intervals of 2 seconds.

Display 50 2

Setting

ON

OFF

Display

50H

Z

60H

Z

60

10

Leading

10°

Leading

45°

45

MPD-1,2

MPD-3

3

HO.

Self holding

Self reset

FU.

RUN indicated LED（Green）

Continuously monitor the auxiliary power supply circuit, electric circuit, program data, etc., and the

RUN LED lights up in normal condition.

Test switch

By pressing the TEST button, forced operation is available.

Display reset lever on the operation flag unit

Pushing reset lever makes it possible to reset the operation display unit.

While the lever is being pushed up, the relay function is locked.

Note）Since the display plug of the operation display unit is of a very precise structure, avoid touching it directly by hand.

Selector switch for display selection

●

Set the display item

●

To change the setting with hand or a small (-) screwdriver.

Switches for V

0

, I

0

and operation time setting

●

Set the setting value

●

To change the setting with hand or a small (-) screwdriver.

Operating conditions setting switch

●

Frequency

●

Maximum senility angle (operating phase)

●

Used ZVT

●

Output contact reset system

The above operating condition can be set with the

ON/OFF switch.

Example 1: 50H

Z

-leading 45°（isolated system）

<Case of self-holding and MPD-3 using>

↓

ON

1 2 3 4

OFF

Example 2: 60H

Z

-leading 10°(reactor grounding system)

<Case of self-reset and MPD-2 using>

↓

1 2

ON

3 4

OFF

When the switch is set, do not use any tool with a sharp point. (It may cause damage to the switch lever.)

Operation flag indicator

During relay operating, this indicator changes from black to orange.

Fig. 3-2 MDG-A1 series construction（panel）

10 JEP0-IL9370

5. Operation Description

5.1 Relay Function

① This relay has a built-in regulated voltage circuit which derivers control voltage from the voltage (VT secondary voltage) input, therefore, particular control power supply is not required.

②Set the respective operating conditions (frequency , maximum operating sensitivity angle, combined ZVT and output contact) with the operating condition setting switch.

③Zero phase voltage input is supplied from secondary output of type MPD-2 or MPD-3 zero-phase voltage detector combined with the relay. And this zero-phase voltage will be changed to digital signal by a A/D converter and as data input microcomputer.

Zero phase voltage input, after passing through the filter circuit, is derived to Vo expanded output terminals (M .N) through small current transformer as a signal or Vo expansion besides the above.

④Zero phase current input is supplied from secondary output of type MZT zero-phase current detector combined with the relay.

And this zero-phase current will be changed to digital signal by a A/D converter and as data input microcomputer.

⑤To judge the direction based on the phase relation of zero-phase voltage and zero-phase current.

⑥ The microcomputer allows level judgment and computation by comparison of zero phase current and voltage signal data with the respective set point data, while the operation phase is jugged and computed with each rectangular wave data. If both zero phase current signal and zero phase voltage signal exceed the setting value, reaching the operation phase, the timer starts, and if the signals are present continuously longer than the operation time setting value the output relay and operation flag unit are actuated.

5.2 RUN Indication（Self-monitoring Function）

This relay monitors control voltage, electric circuit and

Program data at all time. The green LED (RUN) lights up in the normal condition, and goes out in the abnormal condition. Since control voltage is derived from VT secondary voltage input, the

LED goes out when the control voltage lower than approx. 85V.

5.3 Fault Record Function

When a fault occurs, the relay will output an operating signal, and as the same time the operating information (Vo, Io, phase) will be record. It can save and update the last 2 times fault records.

The fault records are save in a static memory inside relay, thereby the fault records can be read again after re-put power on.

About the fault record reset, please refer the item of ４.⑨

5.4 Numerical Display Function

By change the position of the selector switch, the following values can be displayed on the numerical display LED.

①Vo measurement（％）…（switch position：0）…

According to zero phase voltage signal data, zero phase voltage is measured and computed, then to display the input value of

Vo. The display range is 1.0% to 12.0%. (When more than 12.0%,

“O.F.” is displayed. And when less than 1.0%, nothing be displayed)

Here, “100%” denotes the 6.6 kV system: 3,180V is obtained with single phase completely grounded, and 7 V is obtained with

MPD type ZVT secondary output voltage.

This function makes it possible to measure residual Vo detection sensitivity setting.

②I

0

measurement（A）…（switch position：1）…

According to zero phase current signal data, zero phase current is measured and computed, then to display the input value of

I

0

. The display range is 0.05A to 1.5A.

（when less than 0.05A, nothing be display. When more than 1.5A,

“O.F.” is displayed.）

③Phase measurement（°）…（switch position：2）…

According to zero phase voltage and zero phase current signal data, phase is measured and computed, then to display the I

0 phase based on Vo. The display range is 0°to 359°(lag).

④Vo, Io pick up…（switch position：3）…

When the V

0

and I

0

input exceed each setting value,

U. ― I.

is displayed.

When set switch position 3 ― is displayed,

When the input are more than each settings (Vo and Io setting)

U. ― I. is displayed.

(Vo pick up： U. ― Io pick up： ― I. ）

Using this function, easy to test the Min. operating value.

When pressing the TEST button U. ― I. is displayed

⑤Setting value display…（Switch position：4～6）…

This function displays the relay setting condition: it displays the zero phase voltage Vo settings（％）, zero phase current

Io settings（A）and operation time T settings（ｓ）.

⑥Operating condition display…（Switch position：7）…

Once set the operating conditions setting switch on 7, with the setting of SW1～4, the following contents will be displayed in sequence at intervals of 2 seconds and then the LED goes out.

If you want to display it again, please change the display switch to other position first, and then return back position 7 again.

Setting(example) 50H

Z

Display 50 leading10° MPD-1.2

Self-holding

10 2 HO.

Setting(example) 60H

Z leading45° MPD-3 Auto-reset

Display 60 45 3 FU.

⑦Fault records（Newest）display…（Switch position：8～A）…

To display the newest fault data including V

0

, I

0

and phase ※ value recorded when fault occurred.

⑧Fault records（last time）display…（Switch position：B～D）

To display the fault data including V

0

, I

0

and phase ※ value recorded when fault occurred last time.

⑨fault records reset…（Switch position：E）…

This function uses to clear all of fault records.

When set the switch on this position and holding 5s, “O.K.” will be displayed, all of the fault record data will be cleared.

※The display range of the I

0

phase based on the V

0

is 0°to 359°

(lag)

11 JEP0-IL9370

6. Application Example

a) Single circuit

ZCT

“ MZT ”

３

DS

CB

PCT

ZVT(ZPD)

“ MPD

MDG-A1V

” b) Multiple circuits （Directly supply V

0

from MPD type ZVT）

MDG-A1V

ZCT

“ MZT ”

３

PCT

DS

ZVT

“ MPD ”

CB

CB

ZCT

“ MZT ”

３

CB

MDG-A1V

ZCT

“ MZT ”

３

MDG-A1V

In case of MPD-2 type ZVT: V

0

supply to Max. 10 units available

In case of MPD-3 type ZVT: V

0

supply to Max. 5 units available c) Multiple circuits (Directly supply V

0

from MPD type ZVT and V

0

expansion terminals（M,N）of MDG-A1 type relay)

MDG-A1V

ZCT

“ MZT ”

３

CB CB CB

DS

CB

PCT

CB

“

ZVT

MPD

ZCT

“ MZT ”

３

MDG-A1V

ZCT

“ MZT ”

３

MDG-A1V

ZCT

“ MZT ”

３

MDG-A1V

ZCT

“ MZT ”

３

MDG-A1V

”

CB CB

ZCT

“ MZT ”

３

MDG-A1V

ZCT

“ MZT ”

３

MDG-A1V

※

The ※ marked part means that the V

0 is supplied from V

0

expansion terminals（M,N）of MDG-A1 type relay.

Consider that the MDG-A1V relays which supplies V

0

for expansion is supplied with V

0 directly from the MPD type ZVT. 20 relays can be connected for per unit.

Fig. 3-3 Application of MDG-A1V type relay

Note）For type MPD-2, provide DS or PCS on ZVT primary side please.

12 JEP0-IL9370

７．External Connection Diagram (Example)

ZCT

“MZT”

K

L

AC110V kt lt k Z1

P1 P2

MDG-A1V l Z2

(M)

Y1

(N)

Y2 E a11 a12 a21 a22

(E

D

)

PCT

VT PF

DS

AC110V

To P1-P2 of

MDG-A1V-R

(E D )

CB

BP

To alarm circuit

Voltage tripping coil

N N

MPD-3W type special shield cable

52a

Pallet switch

T

BN

MPD-3C type high-voltage capacitor

N

N

MPD-3T type transformer box

Y1(50Hz)

Y1(60Hz)

Y2

E

(E A ) (E D )

CB

K

ZCT

“MZT”

L

CB CB CB

AC110V

ZCT kt lt k Z1 l Z2

P1 P2

MDG-A1V

(M) (N)

Y1 Y2 E

M

N

MDG-

A1V

As left

Y1 Y2 E

ZCT

MDG-

A1V

As left

Y1 Y2 E

K

ZCT

“MZT”

L

(E D )

(E

D

) (E

D

)

CB

AC110V kt k Z1 l Z2

P1 P2

MDG-A1V

(M) (N)

Y1 Y2 E lt

ZCT

“MZT”

M

K

N

L

(E

D

)

(E

D

)

CB

AC110V kt lt k Z1 l Z2

P1 P2

MDG-A1V

(M) (N)

Y1 Y2 E

M

N

(E

D

)

ZCT

MDG-

A1V

As left

Y1 Y2 E

(E D )

Notes）

1.For write materials from ZCT and ZVT to the relay , and write materials for connection from V

0

expansion terminals（M-N）,use

2-core shielded wire of 0.75～1mm 2 please.

The both ways load shall be less than 5 Ω.(The cable length, at case of 0.75mm

2 2-core shield, is approx.

less than 100m one way.)

2.In case of multiple relays connected with ZVT, supply V

0 to each feeder, from V

0 expansion terminals（M、N） of MDG-A1V relay please. (Max. 20 relays can be connected. but for the MPD-2, Max.10 relays can be connected, and for the MPD-3, Max. 5 relays can be connected.)

3.The MDG-A1V relay which supplies V

0 to other units shall receive V

0

directly from the MPD type .

4.The CB tripping circuit and alarm circuit of MDG-A1V relay for feeder protection are omitted in this figure above.

But the corresponding circuit of the power receiving part is required

5.In this figure the voltage tripping system is shown. For CT tripping, the MGX-1 type auxiliary box is necessary.

6.For MDG-A1V-RD type relay, please connect terminals Z

2

and Y

2

with 2mm 2 cable when sub-unit is drew out.

7.Do not connect the “l” terminal of MZT type ZCT to ground please.

8.If ZVT is of a type MPD-2, provide DS or PCS at the primary side of ZVT please.

図 3-4 External Connection Diagram

13 JEP0-IL9370

８．Setting and Operation conditions setting

8.1 Setting (1) Frequency

Normally, the operating values are set as follow, but When use 50Hz, set SW-No.1 to ON position (up side). these values should be set with due consideration given to various conditions of the systems, such as residual voltage and current, and protection coordination.

＜Sample setting of MDG relay＞

・Power receiving point：

I

0

＝0.2～0.4A（※）

V

0

＝5～10％ （※） T＝0.2～0.3ｓ（※）

・Branch feeder：

I

0

＝equivalent to power receiving point or smaller

V

0

＝5～10％ （※） T＝Instantaneous（Approx.75ms）

※ about the setting, please discussion with electric power company and then set it.

In addition, when take V

0

setting, can set it more than

V

0 measured value in order to avoid unwanted operation.

8.2 Operating conditions setting

All of operating condition switch is set OFF position at time of shipment. Set it according to operating

And when use 60Hz, set SW-No.1 to OFF position (down side) please.

(2) Max. sensitivity angle

For a reactor-grounding system, set SW-No.2 to ON position (up side). And for a isolated system, set

SW-No.2 to OFF position (down side).

(3) Combined ZVT

When combined with zero-phase voltage detector MPD-2 type, set SW-No.3 to ON position (up side). And when combined with zero-phase voltage detector MPD-2 type, set SW-No.2 to OFF position (down side). In addition, when combined with zero-phase voltage detector MPD-1 type, also set SW-No.3 to ON position (up side).

(4) Output contacts

If you want to set output contacts self-holding, please set SW-No.4 to ON position (up side). And if you want to set output contacts auto-reset, please set

SW-No.4 to OFF position (down side).

conditions when beginning use please.

9. Precautions for Design and Installation

＜Connection＞

(1) ZCT test terminal

Use the test terminals K t and l t of the zero phase current transformer only when letting dummy fault current flow during the test, and keep them open after the test.

（If short circuit, relay does not operate.）

(2) Wiring material

Since the MDG-A1 is a high sensitivity static type relay, it is necessary to suppress surge and noise from the main circuit and other contact lines where applicable.

Consequently, use a 0.75 to 1mm 2 2-core shielding cable

(black/white) to connect ZCT with terminals (Z1, Z2,

Y1, Y2, M, N) of relay, and connect the shield with relay terminal “E”.

In this case, both ways load shall be less than 5 Ω.

(The cable length, at case of 0.75mm

2 2-core shield, is approx.

less than 100m in one way.)

(3) Polarity

Polarity is very important to this relay. Please pay a special care to polarity for connecting ZCT and ZVT with relay.

(Refer to the external connection diagram)

Grounding point is also important. Please pay attention to.

(4) ZVT position

The position of ZVT is not related to CB power supply and load side in characteristics and protection.

(5) ZVT protection：

For MPD-2 type ZVT, insert a fuse（MITSUBIHSI PL-G type

7.2/3.6KV T1A） or cut-out into each phase at the high voltage side.

For MPD-3 type ZVT, DS is not required.

(6) Power cable shield earth

When an electric power cable is used at the primary side of ZCT, note the shield earth as specified is the

“shield Earth” section is “Guideline for

High-voltage Power Receiving & Distribution

Facilities”.

(7) Power cable handing

Take care in handing not to damage the outer sheath

14 JEP0-IL9370

of ZCT primary conductor.

The bending radius should be more than 10 times the conductor outside diameter. Locate the cable symmetrically in 3-phase in the ZCT thru-section.

(8) ZVT grounding and case. For MPD-3 type , provide Class A grounding for terminal “Ｅ”.

(9) MDG-A1V relay grounding

Since terminals Z

2

-Y

２ are short-circuited inside the

MDG-A1V relay, ground only Y

２

terminal of MPD-2/MPD-3 type ZVT or MDG-A1V type relay. It is better to ground

Y

２ terminal of ZVT.

When V

0

expansion terminal is used, ground only N terminal of the MDG-A1V relay.

10. Handling Method

10.1 Panel assemble

①Do connect the relay terminal “E” to earth at Class D please.

＜Withstand voltage test＞

(1) When the test is performed between high-voltage circuit to earth, and high-voltage circuit to low-voltage circuit after the relay is assembled into panel, make sure that ZVT secondary side (or ZCT secondary side) and VT secondary side grounding is provided.

When V

0

expansion terminal is used, make sure that to ground N terminal of the MDG-A1V relay.

(2) For the test between low-voltage circuit and earth, make sure that to remove the ZVT secondary side (or

ZCT secondary side) and VT secondary side from earth.

When V

0

expansion terminal is used, make sure that to remove N terminal of the MDG-A1V relay from earth.

②Type MDG-A1V-RD is a draw-out type that the sub-unit can be drawn out from case.

For detail, refer to section of “Drawing out and Housing operation of Sub-unit” please.

10.2

Use and operation

①Before in-service, the setting suitable for the operating conditions (frequency, phase characteristics, combined ZVT and output contact reset system)is required for operation by the operating condition setting switch.

② Avoid changing the settings during operation, since it is possible to occurs unwanted operation. However, if setting change is unavoidable, please push up the display reset lever in order to lock relay operating.

③To change the setting may be realized manually by the setting switch. It is also possible by using a small minus (-) screwdriver. If a large minus (-) screwdriver is used, it may damage the groove of the switch knob.

④The switch for setting is a rotary one utilizing snap action. When the setting is changed, turn the switch smoothly so as not to stop it in mid-position.

⑤The position of the display selector switch is not specified in particular, but if it is normally set to

0 V

⑥Since the RUN indicator LED is lighting during the normal operation, check it in routine checking, for example. When it is OFF, check VT secondary input voltage value, and if it is still OFF even OFF at apporox.85v or more, contact our local agent and branch office since the relay may fail.

15 JEP0-IL9370

11. Test

This equipment (relay, ZCT) is factory tested sufficiently before shipment. In the following cases, however, it is recommended that the test be carried out. a. After the products are unpacked when received b. When the equipment starts operation

(Power receiving starts) c. When periodical checkup is carried out

(Normally once per year)

11.1 Testing

①For voltage and current input waveforms, use a sine wave without distortion please.

②To select the switch for each setting with hand or use a small regular screwdriver.

③Adjust selector switch position to V

0

Measure(%)

１ I

0

Measure(A) ２ Phase Measure ( ° ) ３ V

0

/I

0

pick up as appropriate according to the test item. Set other switches for setting according to the test conditions in the operation characteristic control points.

④If the operation characteristics are tested specially in individual control points (for example, when tested with the in-service setting conditions), the test should be performed with the operation characteristic points when the products are received, a receiving test should be carried out with individual control point after judging the performance of this relay. Please use this data as a later standard.

11.2 Withstand Voltage Test

Perform the unit test as follows. a. Do not input voltage to Z

1

-Z

2

circuit please. b. Apply 2000V AC （commercial frequency）between all electric circuits and case (E terminal) for one minute, and make sure that no problem.

Voltage Applied Terminals

Y1 Z1

Y2 Z2

P1 M a11 a12

P2 N a21 a22

E

P1

Y1

Z1

M

P1

P1

P1

Y1

Terminals Voltage Applied

P2

Y2

Z2

N

P2

P2

P2

Y2 a11 a12 a21 a22 a11 a12 a21 a22 a11 a12 a21 a22 a11 a12 a21 a22

Y1

Z1

M

M

Y2

Z2

N

N

Z1 Z2 M N

Note） Do not apply test voltage between ○ ○ ○ ○

11.3 Operation Characteristic Test

[Combined with MDG＋ZCT＋ZVT]

①For job-site test, it is necessary to check the wiring, that is, the directivity is necessary to be checked. For this check, voltage is applied from the primary side

(high-voltage side) of zero-phase voltage detector.

There are two test methods. One is that to combine every equipment to form a test circuit (refer to Fig. 3-5). And the other is that to use a relay tester (refer to Fig.

3-6).

②When this test is carried out, be sure that the main circuit is turned OFF.

③Increase the control voltage gradually, the RUN indicator

LED (green) will light up at approx. 85V.

This indicates that the electronic circuit has started to operate normally.

④With the rated voltage and press the TEST button located relay panel, make sure that the forced operation is available please.

When the display selector switch is set at “3”, once the TEST button is pressed, the display will be changed c. Apply 2000V AC （commercial frequency）between all electric circuits and case (E terminal) for one minute, and make sure that no problem.

16

Note) In the case of that V

0 and I

0 are inputting, it is possible that the relay does not operate even the

TEST button was pressed. That is related to the value of V

0

/I

0 and the phase. At this time, it is not available to test relay operation.

JEP0-IL9370

11.4 Operation Characteristic Control Point

Perform the test periodically according to the following test conditions and criterion.

I

V

0

0

Test Item

Operation

Value

Operation

Value

I

0

settings

All settings

Minimum

V

0

settings

Minimum

Test Condition

All settings

Operating Time

0.2s

0.2s

Inputs

V

0

＝150％ of setting

Value at maximum sensitivity angle

I

0

＝150％ of setting

Value at maximum sensitivity angle

Criterion

±10％ of setting value

±25％ of setting value

Phase

Characteristics

Minimum Minimum 0.2s

V

I

0

0

＝150％ of setting value

＝1000％ of setting value

Maximum sensitivity angle ＝ 45°

（For isolated system）

Lag：25～65°

Lead：115～155°

Maximum sensitivity angle ＝ 10°

（For PC grounding）

Lag：50～85°

Lead：90～130°

Operation Time

Characteristics

Minimum All settings

Instantaneous

0.2s

Other than the above

V

0

＝150％ of

setting value

I

0

＝130％ of setting value

50～100ms ※

0.1～0.3s

Applied at the same time at maximum sensitivity

±20％ of setting value angle

※ The operation time is 50 to 110 ms when this relay is combined with MPD-2 type ZVT.

17 JEP0-IL9370

Make sure that this circuit is open before test.

DS

K

ZCT

“

MZT

”

L kt k l lt

※

※

Z

1

Z

2 a

11 a

12

E

MDG-A1V

Y

1

Y

2

(E

D

)

P

1

P 2

AC100/110V

CB

Tripping coil

AC100V or

DC100V

52a

DS K

Black clip

Red clip kt

ZCT

“MZT” lt

L

※ ※

U V W “ Phase meter ”

MPD-3C

MPD-3W

From ② －

φ

MPD-3T

From

①

＋

T

N

E

Y 1

Y

2

20

Ω

0~1000 Ω

SW

R

1

R

2

(E A ) (E D )

U u

※ ※

AC100/110V 0~1000V

To ①

To ②

P 1 P 2

Voltage

regulator

V

To P 1 , P 2 terminals of MDG v

Fig. 3-5(1) Test Method by Equipments Combination

P

1

VT

P

2

(E

D

)

Remove P1 and P2

MDG-A1V

CB

Remove the fuses a 21 a 22

※ ※

MPD-3C

MPD-3W

MPD-3T

Y

1

Y 2

N

E

T

Red clip

Notes)

These figures show that the test is performed by applying voltage simultaneously in 3-phase to the high-voltage side of MPD-3.MPD-3C.

If the test is performed by applying voltage from MPD-3T test terminal (T), the voltage value should be 1/10 of all 3-pase input at the high voltage side.

Do not apply voltage into terminal “T” more than 380V !

● At the case of that there are not terminals of kt and lt on ZCT,

Please pass the red clip of current element cord through ZCT thru- hole for short circuit with the black clip and turn power on.

● For the relay of MDG-A1V, the input polarity is that:

Z1 with I

0

input and Y2 with V

0 input.

● Do not forget to remove the wires

marked by “ ※ ” in the figures after test.

● When test using the test terminal

“T”, the wires marked by “ ※ ” in the figures are not required.

Z 2 Z 1 P 1 P 2 Y 2 Y 1 a 11 a 12 E

(E D )

Current element cord

Red clip

Black clip

Auxiliary power supply cord

Tripping cord

V A φ

(E D )

(E

A

)

Voltage element cord

Black clip

AC100/110V

Fig. 3-6(1) Test Method Using Relay Tester

18 JEP0-IL9370

DS

K

ZCT

“

MZT

”

L kt k l lt

Make sure that this circuit is open before test

※

※

Z

1

Z

2 a

11 a

12

E

MDG-A1V

Y

1

Y

2

(E

D

)

P

1

P 2

AC100/110V

PF

CB

Tripping coil

AC100V or

DC100V

52a

※ ※

From ②

“ Phase meter ”

－

φ

＋

U V

MPD-2

M

From

① Y

1

Case earth

Y 2

SW

AC100/110V

20

Ω

0~1000 Ω

R

1

R

2

U u

0~1000V

E

(E A )

※

(E

D

)

To ①

To ②

※

P 1 P 2

Voltage regulator

To P 1 and P 2 terminals of MDG

V v

Fig. 3-5(2) Test Method by Equipments Combination

DS K

ZCT

“MZT”

Black clip

Red clip kt lt

L CB

Remove the fuses

Note)

● At the case of that there are not terminals of kt and lt on ZCT,

Please pass the red clip of current element cord through ZCT thru- hole for short circuit with the black clip and turn power on.

● For the relay of MDG-A1V, the input polarity is that:

Z1 with I

0

input and Y2 with V

0 input.

● Do not forget to remove the wires

marked by “ ※ ” in the figures after test.

P

1

VT

P

2

(E

D

)

Remove P1 and P2

U

※

V

※

W

Red clip

MDG-A1V a 21 a 22

MPD-2

Y 1

Y

2

E

Z 2 Z 1 P 1 P 2 Y 2 Y 1 a 11 a 12 E

(E D )

Current element cord

Red clip

Black clip

Auxiliary power supply coed

(E D ) (E A )

Tripping cord

Voltage element cord

Black clip

AC100/110V

V A φ

Fig. 3-6(2) Test Method Using Relay Tester

19 JEP0-IL9370

12. Terminal Layout

Y1 Z1 P1 M a11 a12

E Y2 Z2 P2 N a21 a22

9 9 9 9 9 9

14-M3.5 screw

E

Y1 Z1 P1 M a11 a12

Y2 Z2 P2 N a21 a22

9 9 9 9 9 9

14-M3.5 screw

ＭＤＧ－Ａ１Ｖ－Ｒ

Fig. 3-7 Terminal Layout

ＭＤＧ－Ａ１Ｖ－ＲＤ

● Drawing out and Housing operation of Sub-unit

― For compact cylindrical draw-out type (RD type)

It is available to draw out the sub-unit from the relay case ・ Lock the tripping circuit instead of removing the external wires. So that easier to carry out checking and testing.

When drawing out and housing, please pay attention to not to touch the electric circuit and move the sub-unit by handing the lever or from. Otherwise, it is possible to get an electric shock or make internal electric parts damage.

The following operation should be checked when sub-unit be drawn out from relay case.

・ Turn off the power supply into relay

・ Disconnect CT circuit

・ Disconnect VT circuit

・ Open the auxiliary power supply (only the drawn out relay)

Note) This relay has the function that make the CT secondary automatically short-circuit when draw out the sub-unit from case.

Subunit Connecter of unit

Connecter of sub-unit

Cover

Screw for fixing sub-unit

Fig. 3-8 RD Type Structure of MELPRO-A Series

Draw-out handle

Lever for reset

20 JEP0-IL9370

13. Mounting and Dimensions

155

32

146

114

15

124

φ 140 ～φ 142

15 46.5

8.3

2-M6 screw

14-M3.5 screw

Minimum arrangement pitch 170

2φ 7 hole

Fig. 3-9 Type MOC,MGR,MDG,MUV,MOV,MVG- -R (Unit:mm)

Same as the center lines of φ 140～142 hole

155

32

146

114

36.5

14

124

φ 140 ～φ 142

15 46.5

8.3

2-M6 screw

14-M3.5 screw

Minimum arrangement pitch 182

2φ 7 hole

Fig. 3-10 Type MOC,MGR,MDG,MUV,MOV,MVG- -RD (Unit:mm)

Relay cover is opening-and-closing door type. Once forces the cover overload when open it, it will be removed from case. Please refer to the figure shown below to assemble the cover at horizontal direction.

(Do not assemble it at the direction of the front.）

Hinge

[ Cover opening-and-closing ]

21 JEP0-IL9370

Improvement on the reliability of protection function

Any parts and materials applied to the protection relay have limited life time which will bring the degradation to the relay.

The degree of degradation will be variable and depend on the purpose, period in use, applied circumstance and unevenness on the performance of each part.

MITSUBISHI ELECTRIC CORPORATION design the relay so as to realize that the recommended replaced duration is more them 15 years.

However, there may be some possibilities to occur some defects before reaching 15 years due to above mentioned the degree of degradation of parts and materials being depended on the condition in use.

To prevent unwanted operation or no operation of relay due to above reasons, it is recommended to apply the relay with self-diagnosis function and/or multiplexing relay system such as dual or duplex scheme.

22 JEP0-IL9370

HEAD OFFICE ： 7-3 MARUNOUCHI 2-CHOME, CHIYODA-KU TOKYO, 100-8310, JAPAN

Revised in Jan. 2012