ENGLISH

User manual

 Copyright HT ITALIA 2012

Release EN 2.00 - 19/04/2012

HT321 - HT322

Table of contents:

1.

 

SAFETY PRECAUTIONS AND PROCEDURES .......................................................... 2

 

1.1.

 

Preliminary ........................................................................................................................ 2

 

1.2.

 

During use ......................................................................................................................... 3

 

1.3.

 

After use ............................................................................................................................ 3

 

1.4.

  Measuring (overvoltage) categories definitions ................................................................. 3  

2.

  GENERAL DESCRIPTION ........................................................................................... 4  

3.

 

PREPARATION FOR USE ........................................................................................... 4

 

3.1.

 

Initial .................................................................................................................................. 4

 

3.2.

 

Supply voltage ................................................................................................................... 4

 

3.3.

 

Calibration ......................................................................................................................... 4

 

3.4.

  Storage .............................................................................................................................. 4  

4.

  OPERATING INSTRUCTIONS ..................................................................................... 5  

4.1.

  Instrument description ....................................................................................................... 5  

4.1.1.

 

Front panel description ............................................................................................................... 5

 

4.2.

  Description of function keys .............................................................................................. 6  

4.2.1.

 

HOLD Key................................................................................................................................... 6

 

4.2.2.

 

R (RANGE) Key .......................................................................................................................... 6

 

4.2.3.

 

MAX Key ..................................................................................................................................... 6

 

4.2.4.

 

SEL Key ...................................................................................................................................... 6

 

4.2.5.

 

Backlight key (only HT322) ................................................................................................. 6

 

4.2.6.

 

Auto Power OFF ......................................................................................................................... 6

 

4.3.

  Measurements ................................................................................................................... 7  

4.3.1.

 

DC Voltage measurement .......................................................................................................... 7

 

4.3.2.

 

AC Voltage measurement .......................................................................................................... 8

 

4.3.3.

 

Resistance measurement ........................................................................................................... 9

 

4.3.4.

 

Diode test and Continuity test .................................................................................................. 10

 

4.3.5.

 

Temperature measurement (only HT322) ................................................................................ 11

 

5.

  MAINTENANCE .......................................................................................................... 12  

5.1.

  General information ......................................................................................................... 12  

5.2.

 

Battery replacement ........................................................................................................ 12

 

5.3.

 

Cleaning .......................................................................................................................... 12

 

5.4.

 

End of life ........................................................................................................................ 12

 

6.

 

TECHNICAL SPECIFICATIONS ................................................................................. 13

 

6.1.

  Technical features ........................................................................................................... 13  

6.1.1.

 

Safety ........................................................................................................................................ 14

 

6.1.2.

 

General data ............................................................................................................................. 14

 

6.2.

 

Environment .................................................................................................................... 14

 

6.2.1.

 

Environmental conditions ......................................................................................................... 14

 

6.3.

  Accessories ..................................................................................................................... 14  

6.3.1.

 

Standard accessories ............................................................................................................... 14

 

6.3.2.

 

Optional accessories ................................................................................................................ 14

 

7.

  SERVICE .................................................................................................................... 15  

7.1.

  Warranty conditions......................................................................................................... 15  

7.2.

  After-sale service............................................................................................................. 15  

EN - 1

1. SAFETY PRECAUTIONS AND PROCEDURES

HT321 - HT322

This meter is compliance with safety Standard IEC/EN61010-1 related to electronic measuring instruments. For your own safety and to avoid damaging the instrument follow the procedures described in this instruction manual and read carefully all notes preceded by this symbol .

When taking measurements:

 Avoid doing that in humid or wet places.

 Avoid doing that in rooms where explosive gas, combustible gas, steam or excessive dust is present.

 Keep you insulated from the object under test.

 Do not touch exposed metal parts such as test lead ends, sockets, fixing objects, circuits etc.

 Avoid doing that if you notice anomalous conditions such as breakages, deformations, fractures, leakages of battery liquid, blind display etc.

 Be particularly careful when measuring voltages exceeding 20V to avoid risks of electrical shocks.

The following symbols are used:

CAUTION - refer to the instruction manual - an improper use may damage the instrument or its components.

Danger high voltage: risk of electric shocks.

Double insulated meter.

AC voltage.

DC voltage.

1.1. PRELIMINARY

 This instrument has been designed for use in environments of pollution degree 2

 It can be used for VOLTAGE measurements on installations of CAT III 1000V or CAT

IV 600V

 This instrument is not suitable for AC voltage and current measurements of not sinusoidal signals

 Only the original test leads supplied along with the instrument guarantee compliance with the safety standards in force. They must be in a good conditions and, if necessary, replaced with identical ones

 Do not test nor connect to any circuit exceeding the specified overload protection.

 Do not take measurements under environmental conditions exceeding the limits indicated in § 6.1.1. and § 6.2.1

 Make sure that batteries are correctly installed

 Before connecting the test probes to the installation make sure that the rotary selector is positioned on the right function

 Make sure that LCD and rotary selector indicate the same function

EN - 2

HT321 - HT322

Read the recommendations which follow and the instructions in this manual:

CAUTION

An improper use may damage the instrument and/or its components or injure the operator.

 When changing the range, first disconnect the test leads from the circuit under test in order to avoid any accident

 When the instrument is connected to measuring circuits never touch any unused terminal

 When measuring resistors do not add any voltage. Although there is a protection circuit, excessive voltage could cause malfunctioning.

 If during measurement the displayed values remain constant check whether the HOLD function is active

USE

 After using the instrument turn it off.

 If you expect not to use the instrument for a long period remove the battery to avoid leakages of battery liquids which may damage its inner components.

IEC/EN61010-1: Safety requirements for electrical equipment for measurement, control and laboratory use, Part 1: General requirements, gives a definition of measuring category, usually called overvoltage category. § 6.7.4: Measuring circuits:

(OMISSIS)

Circuits are divided into the following measurement categories:

 Measurement category IV is for measurements performed at the source of the lowvoltage installation.

Examples are electricity meters and measurements on primary overcurrent protection devices and ripple control units.

 Measurement category III is for measurements performed in the building installation.

Examples are measurements on distribution boards, circuit breakers, wiring, including cables, bus-bars, junction boxes, switches, socket-outlets in the fixed installation, and equipment for industrial use and some other equipment, for example, stationary motors with permanent connection to fixed installation.

 Measurement category II is for measurements performed on circuits directly connected to the low voltage installation..

Examples are measurements on household appliances, portable tools and similar equipment.

 Measurement category I is for measurements performed on circuits not directly connected to MAINS.

Examples are measurements on circuits not derived from MAINS, and specially protected (internal) MAINS-derived circuits. In the latter case, transient stresses are variable; for that reason, the norm requires that the transient withstand capability of the equipment is made known to the user.

EN - 3

2. GENERAL DESCRIPTION

HT321 - HT322

This meter performs the herewith measurements:

 DC

 AC sine voltage

 Resistance test test

 Temperature with type K probe (only HT322)

All selectable by means of a 6-position rotary selector (including OFF position). Also are available the HOLD key to hold the displayed value, the R key for manual selection of measure ranges, the MAX key for measure of maximum value and SEL key for selection between diode test and continuity test and temperature measures in °C or °F (only

HT322).

The selected quantity is displayed with indication of measuring unit and active functions.

The instrument disposes of an Auto Power Off function consisting in an automatic switching off 15 minutes after last selector rotation.

3. PREPARATION FOR USE

3.1. INITIAL

This instrument was checked both mechanically and electrically prior to shipment. All possible cares and precautions were taken to let you receive the instrument in perfect conditions. Notwithstanding we suggest you to check it rapidly (eventual damages may have occurred during transport – if so please contact the local distributor from whom you bought the item).

Make sure that all standard accessories mentioned in § 6.3.1 are included. Should you have to return back the instrument for any reason please follow the instructions mentioned in § 7.

The instrument is supplied by 2x1.5V batteries type IEC AAA LR03. When batteries are low, a low battery indication is displayed. To replace/insert batteries please refer to § 5.2.

3.3. CALIBRATION

The instrument complies with the technical specifications contained in this manual and such compliance is guaranteed for 1 year. Annual recalibration is recommended.

3.4. STORAGE

After a period of storage in extreme environmental conditions exceeding the limits mentioned in § 6.2.1 let the instrument resume normal measuring conditions before using it.

EN - 4

4. OPERATING INSTRUCTIONS

4.1.1. Front panel description

HT321 - HT322

CAPTION:

1. LCD

2. HOLD Key

3. R Key

4. MAX Key

5. SEL Key

6. Backlight Key(For HT322)

7. Function selector

8. COM input terminal

9. V

 input terminal (for 321) COM and V



HT322)

°C/°F input terminal (for

Fig. 1: Instrument description

EN - 5

4.2. DESCRIPTION OF FUNCTION KEYS

HT321 - HT322

By pressing HOLD key the measured value is frozen on the display where the symbol

"HOLD" appears. Pressing again HOLD to disable this function and resume normal operation.

4.2.2. R (RANGE) Key

By pressing R key, the manual mode is activated and the “AUTO” symbol disappears from the display. Press R cyclically to change the measuring range and fix the decimal point on the display.

To exit this function keep R key pressed for at least 1 second or rotate the selector to another position.

By pressing MAX key, maximum value are measured. The symbol corresponding “MAX” is displayed. This value is stored and automatically updated as soon as an higher value is measured by meter. Press MAX key again or rotate the selector to another position to exit from this function.

By pressing SEL key the selection of a double measured functions which are present at display is possible. In particular this key is active only in

/ position to select between diode test and continuity test or in °C°F position (only HT322) position to select between

°C and °F temperature measure.

4.2.5. Backlight key (only HT322)

By pressing and hold key for about 3s it’s possible to activate the backlight function on the display. By pressing and hold key again for about 3s to exit from the function or waiting the automatically disable after some seconds. The function is available on each position of the rotary selector.

4.2.6. Auto Power OFF

The instrument automatically turns off 15 minutes after last pressure of keys or last selector rotation. To resume operation turn the selector on OFF and turn on the instrument again.

EN - 6

HT321 - HT322

4.3.1. DC Voltage measurement

CAUTION

The maximum input for DC voltage is 600V. Do not attempt to measure higher voltages to avoid electrical shocks or damages to the instrument.

Fig. 2: Using the meter for DC Voltage measurement

1. Switch on V .

2. Pressing the R key to select the correct range or using the Autorange feature (see §

4.2.2). If the voltage value under test is unknown, select the highest range.

3. Insert the test leads into the jacks, the red plug into V



(for HT321) /

V



°C°F (for HT322) jack and black plug into COM jack.

4. Connect the red and black test leads to the positive and negative poles of the circuit under test respectively (see Fig. 2). The voltage value is displayed

5. If the message "O.L" is displayed select a higher range

6. The symbol "-" on the instrument display indicates that voltage has opposite direction with regard to the connection of Fig. 2

7. For HOLD function and Maximum value measurement please refer to § 4.2

EN - 7

4.3.2. AC Voltage measurement

CAUTION

HT321 - HT322

The maximum input for AC voltage is 600V. Do not attempt to measure higher voltages to avoid electrical shocks or damages to the instrument.

Fig. 3: Using the instrument for AC Voltage measurement

1. Switch on

2. Pressing the R key to select the correct range or using the Autorange feature (see §

4.2.2). If the voltage value under test is unknown, select the highest range

3. Insert the test leads into the jacks, the red plug into V



(for HT321) /

V



°C°F (for HT322) jack and black plug into COM jack

4. Connect the test leads to the circuit under test (see Fig. 3). The voltage value is displayed

5. If the message "O.L" is displayed select a higher range

6. For HOLD function and Maximum value measurement please refer to § 4.2

EN - 8

HT321 - HT322

CAUTION

Before taking resistance measurements in circuit remove power from the circuit being tested and discharge all capacitors.

Fig. 4: Using the instrument for Resistance measurement

2. Pressing the R key to select the correct range or using the Autorange feature (see §

4.2.2). If the resistance value under test is unknown, select the highest range.

3. Insert the test leads into the jack, the red plug into V



(For HT321) / V



(For HT322) jack and black plug into COM jack.

°C°F

4. Connect the test leads to the circuit under test (see Errore. L'origine riferimento non

è stata trovata.). The resistance value is displayed

5. Indications as ".value

k



" or ".value

M



" (respectively for 2k

 or 2M) mean

0.valuek

 and 0.valueM. The zero before comma is not displayed.

6. If the message "O.L" is displayed a higher range must be selected.

7. For HOLD function and Maximum value measurement please refer to § 4.2.

EN - 9

4.3.4. Diode test and Continuity test

CAUTION

HT321 - HT322

Before taking resistance measurements in circuit remove power from the circuit being tested and discharge all capacitors.

Fig. 5: Using the instrument for Diode test

1. Switch on /

2. Insert the test leads into the jack, the red plug into V



(for HT321) / V



°C°F

(for HT322) jack, and black plug into COM jack (see Fig. 5)

3. Connect the test leads to the diode under test observing the proper polarities indicated in

Fig. 5. The threshold voltage value expressed in mV under this situation is displayed

4. If the message "O.L" is displayed the diode terminals are reversed, the diode P-N junction is damaged

5. For Continuity test switch on

/ then push “SEL” button

6. Insert the test leads into the jack, the red plug into V



(for HT322) jack and black plug into COM jack

(for HT321) /

V



°C°F

7. Connect the test leads to the circuit under test (see Fig. 4)

8. The resistance value is displayed and the instrument emits a sound signal if the resistance value is <120



9. The message "

2k



O.L.

" on the display indicates that the resistance value is higher than

EN - 10

HT321 - HT322

Fig. 6: Using the instrument for Temperature measurement

1. Switch on °C°F.

2. Pressing SEL key to select °C or °F measurements

3. Insert the T10 adapter optional accessory into

V

 respect of red and black colours (see Fig. 6)

°C°F

jack, and COM jack with

4. Connect the optional K probe (see § 6.3.2) into the adapter with respect the correct positive and negative polarity then reading will be displayed

5. For HOLD function and Maximum value measurement please refer to § 4.2

EN - 11

5. MAINTENANCE

HT321 - HT322

This is a precision instrument. To guarantee its performances be sure to use it according to these instructions and keep it stored on suitable environmental conditions. Do not expose it to high temperatures or humidity or direct sunlight. Be sure to turn it off after use. If you expect not to use the instrument for a long period remove batteries to avoid leakages of battery liquid which could damage the its inner components.

When the low battery indication " " is displayed the batteries are to be replaced.

CAUTION

Before replacing the battery disconnect test leads from any energised circuits to avoid electrical shocks.

1. Turn off the instrument.

2. Disconnect the test leads from the input terminals.

3. Remove the fixing screws from the back case and detach it.

4. Replace the battery with a new one of the same type (refer to § Errore. L'origine

riferimento non è stata trovata.) observing the proper polarities.

5. Replace the back case and screws.

6. Use the appropriate battery disposal methods for your area.

5.3. CLEANING

To clean the instrument use a soft dry clothe. Never use a wet cloth, solvents or water.

5.4. END OF LIFE

Caution: this symbol indicates that equipment and its accessories shall be subject to a separate collection and correct disposal

EN - 12

6. TECHNICAL SPECIFICATIONS

HT321 - HT322

Accuracy is indicated as [%reading + (number of digits*resolution)] at 23°C±5°C,<75%HR

DC Voltage

Range Resolution Accuracy Input Impedance Overload protection

200mV 0.1mV

10M



600VDC/ACrms

200V 0.1V

AC Voltage

Range Resolution

Accuracy

(45

 400Hz)

2V 0.001V

Input Impedance Overload protection

10M



600VCC/CArms

Resistance

Range Resolution Accuracy

Max Open

Loop Voltage

200

 0.1

2k

 0.001k

20k

 0.01k

200k

 0.1k

2M

 0.001M

20M

 10k

Diode Test

(1.0%rdg + 8dgt)

(1.0%rdg + 3dgt)

(3.0%rdg + 3dgt)

About 3.0V

Range Resolution

1mV

Max Open

Loop Voltage

About 1.5Vdc

Continuity Test

Range Beeper

<120



Temperature with K probe (only HT322)

Max Open Loop

Voltage

About 1.5Vdc

Overload protection

600VDC/Acrms

(<30sec.)

Overload protection

600Vrms (< 30sec.)

Overload protection

600Vrms (< 30sec.)

Range Resolution Accuracy Overload protection

-40°C ÷ 1°C

0°C ÷ 800°C

-40°F ÷ 31°F

32°F ÷ 1382°F

1°C

1

°F

5°C

(2.0%rdg + 3dgt)

9°F

(2.0%rdg + 5dgt)

600VDC/Acrms (<30sec.)

EN - 13

6.1.1. Safety

The instrument complies with:

Insulation:

Pollution degree:

Overvoltage category:

Max height of use:

6.1.2. General data

Mechanical characteristics

Dimensions (L x W x H):

Weight (including battery):

Power supply

Battery type:

Indication of low battery:

Battery life:

Display

Specifications:

6.2. ENVIRONMENT

IE/EN61010-1 double insulation

2

CAT III 1000V, CAT IV 600V

2000m (6561ft)

280g (9.9 ounces)

2 x1.5V batteries type AAA MN2400 LR03 AM4 symbol " " is displayed

Approx. 220 hours

3½ LCD with max. reading 1999 counts + symbol and decimal point

HT321 - HT322

163 x 88 x 48mm (6.4 x 3.5 x 1.9in)

Reference temperature:

Working temperature:

Relative humidity:

Storage temperature:

Storage humidity:

23 ± 5°C; 73 ± 41°F

-5 ÷ 40°C; 23 ÷ 104°F

<80% HR

-10 ÷ 60°C; 14 ÷ 140°F

<70% HR

This product conforms to the prescriptions of the European directive on low voltage

2006/95/EEC (LVD) and to EMC directive 2004/108/EEC.

6.3. ACCESSORIES

6.3.1. Standard

 Test

 Batteries

 B80: carrying case manual

Couple of test leads

Adapter for connection type K probe (HT322 only)

K-type probe for air and gas temperature (HT322 only)

K-type probe for semisolid substance temperature (HT322 only)

K-type probe for liquid substance temperature (HT322 only)

K-type probe for surface temperature (HT322 only)

K-type probe for surface temperature with 90° tip (HT322 only)

Cod. 4413-2

Cod. T10

Cod. TK107

Cod. TK108

Cod. TK109

Cod. TK110

Cod. TK111

EN - 14

7. SERVICE

HT321 - HT322

This instrument is guaranteed against material or production defects, in accordance with our general sales conditions. During the warranty period the manufacturer reserves the right to decide either to repair or replace the product.

Should you need for any reason to return back the instrument for repair or replacement take prior agreements with the local distributor from whom you bought it. Do not forget to enclose a report describing the reasons for returning (detected fault). Use only original packaging. Any damage occurred in transit due to non original packaging will be charged anyhow to the customer.

The manufacturer will not be responsible for any damage to persons or things.

The warranty doesn’t apply to:

 Accessories and batteries (not covered by warranty).

 Repairs made necessary by improper use (including adaptation to particular applications not foreseen in the instructions manual) or improper combination with incompatible accessories or equipment.

 Repairs made necessary by improper shipping material causing damages in transit.

 Repairs made necessary by previous attempts for repair carried out by non skilled or unauthorized personnel.

 Instruments for whatever reason modified by the customer himself without explicit authorization of our Technical Dept.

The contents of this manual may not be reproduced in any form whatsoever without the manufacturer’s authorization.

Our products are patented and our logotypes registered. We reserve the right to modify specifications and prices in view of technological improvements or

developments which might be necessary.

Shouldn’t the instrument work properly, before contacting your distributor make sure that batteries are correctly installed and working, check the test leads and replace them if necessary. Make sure that your operating procedure corresponds to the one described in this manual.

Should you need for any reason to return back the instrument for repair or replacement take prior agreements with the local distributor from whom you bought it. Do not forget to enclose a report describing the reasons for returning (detected fault). Use only original packaging. Any damage occurred in transit due to not original packaging will be charged anyhow to the customer.

The manufacturer will not be responsible for any damage to persons or things.

EN - 15