ENGLISH
User’s manual
© Copyright HT ITALIA 2008 Release EN 1.03 - 04/02/2008
HT37 - HT39
Content:
1. SAFETY PRECAUTIONS AND PROCEDURES..........................................................3
1.1. Preliminary.............................................................................................................3
1.2. During use.............................................................................................................4
1.3. After use................................................................................................................4
1.4. Measuring (overvoltage) categories definitions .....................................................5
2. GENERAL DESCRIPTION...........................................................................................6
2.1. Mean value and TRMS: definition..........................................................................6
2.2. True root mean square value and crest factor: definition.......................................6
3. PREPARATION FOR USE...........................................................................................7
3.1. Initial......................................................................................................................7
3.2. Supply Voltage ......................................................................................................7
3.3. Calibration .............................................................................................................7
3.4. Storage..................................................................................................................7
4. OPERATING INSTRUCTIONS.....................................................................................8
4.1. Instrument Description...........................................................................................8
4.1.1. Front panel................................................................................................................... 8
4.2. FUNCTION Keys...................................................................................................9
4.2.1. MIN MAX...................................................................................................................... 9
4.2.2. PEAK/∆ ........................................................................................................................ 9
4.2.3. RANGE ........................................................................................................................ 9
4.2.4. HOLD........................................................................................................................... 9
4.2.5. RS-232 for connection to PC (HT39 only).................................................................. 10
4.2.6. BACKLIGHT
4.2.7. Disable AutoPowerOFF ............................................................................................. 10
(HT39 only)..................................................................................... 10
4.3. Measurements.....................................................................................................11
4.3.1. DC Voltage measurement.......................................................................................... 11
4.3.2. AC Voltage measurement.......................................................................................... 12
4.3.3. DC Current measurement.......................................................................................... 13
4.3.4. AC Current Measurement.......................................................................................... 14
4.3.5. Frequency measurement........................................................................................... 15
4.3.6. Resistance measurement .......................................................................................... 16
4.3.7. Diode test and continuity test..................................................................................... 17
4.3.8. Capacitance measurement........................................................................................ 18
5. MAINTENANCE..........................................................................................................19
5.1. General Information.............................................................................................19
5.2. Battery Replacement...........................................................................................19
5.3. Fuse Replacement ..............................................................................................20
5.4. Cleaning ..............................................................................................................20
5.5. End of life ............................................................................................................ 20
6. TECHNICAL SPECIFICATIONS................................................................................. 21
6.1. Technical Features..............................................................................................21
6.1.1. Electrical specifications.............................................................................................. 22
6.1.2. Safety......................................................................................................................... 22
6.1.3. General data .............................................................................................................. 23
6.2. Environment ........................................................................................................23
6.2.1. Environmental conditions........................................................................................... 23
6.2.2. EMC and LVD............................................................................................................ 23
6.3. Accessories.........................................................................................................23
7. SERVICE....................................................................................................................24
7.1. Warranty Conditions............................................................................................24
7.2. Service ................................................................................................................ 24
EN - 1
HT37 - HT39
1. SAFETY PRECAUTIONS AND PROCEDURES
This instrument conforms with safety Standard EN 61010-1 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 shock.
Double insulated meter.
AC voltage or current.
DC voltage or current.
1.1. PRELIMINARY
• This instrument has been designed for use in environments of pollution degree 2.
• It can be used for VOLTAGE and CURRENT measurements on installations of
overvoltage category III 1000V and IV 600V.
• When using the instrument always respect the usual safety regulations aimed at:
♦ Protecting you against the dangerous electric currents.
♦ Protecting the instrument against incorrect operations.
• Only the leads supplied with the instrument guarantee compliance with the safety
standards in force. They must be in good conditions and, if necessary, replaced with
identical ones.
• Do not test or connect to any circuit exceeding the specified overload protection.
• Do not effect measurements under environmental conditions exceeding the limits
indicated in paragraph 6.2.1.
EN - 2
HT37 - HT39
• Make sure that batteries are properly installed.
• Before connecting the test probes to the installation, make sure that the function
selector is positioned on the required measurement.
• Make sure that LCD and function selector indicate the same function.
1.2. DURING USE
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.
1.3. AFTER 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.
EN - 3
HT37 - HT39
1.4. MEASURING (OVERVOLTAGE) CATEGORIES DEFINITIONS
The norm EN 61010-1: Safety requirements for electrical equipment for measurement,
control and laboratory use, Part 1: General requirements, defines what measuring
category, usually called overvoltage category, is. On paragraph 6.7.4: Measuring circuits, it
says:
(OMISSIS)
circuits are divided into the following measurement categories:
• Measurement category IV is for measurements performed at the source of the
low-voltage 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 - 4
HT37 - HT39
2. GENERAL DESCRIPTION
This instrument performs the following measurements:
• DC and AC TRMS Voltage.
• DC and AC TRMS Current.
• Resistance and Continuity test.
• Diode test.
• Frequency.
• Capacitance.
All selectable by means of a 10-position function selector (including OFF position).
FUNCTION keys are also available (see chapter 4.2). An analogical bargraph is also
available. 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 30 minutes after last pressure on keys or rotation of selector. To resume
normal operation turn the selector on OFF and switch it on again.
2.1. MEAN VALUE AND TRMS: DEFINITION
Safety testers for AC quantities are divided in two big families:
• MEAN VALUE instruments, measuring only the value of the wave at the fundamental
frequency (50 or 60 Hz).
• TRUE ROOT MEAN SQUARE (or “TRMS”) instruments, measuring the true root mean
square value of the quantity under test.
In presence of a perfectly sinusoidal wave, both families provide identical results. While in
presence of distorted waves, readings are different. Mean value instruments provide only
the value of the fundamental wave while TRMS instruments provide the value of the entire
wave, including harmonics (within the passband of the instrument). Accordingly, if the
same quantity is measured with both kinds of instruments, the measured values are
identical only if the wave is purely sinusoidal. Should it be distorted, TRMS instruments
provide higher values than MEAN VALUE instruments.
2.2. TRUE ROOT MEAN SQUARE VALUE AND CREST FACTOR: DEFINITION
The effective current value is defined as follows: “In an interval of time equivalent to a
period, an alternate current with effective value having an intensity of 1A, by passing on a
resistor, disperses the same energy which would be dispersed in the same period of time
by a direct current having an intensity of 1A”. From this definition comes the numerical
+Tt
0
1
expression: G=
T
The Crest Factor is defined as the ratio between the Peak Value of a signal and its
effective value: CF (G)=
for a purely sinusoidal wave it’s worth
assumes higher values as long as the wave distortion is higher.
2
dttg
)(
∫
t
0
The effective value is indicated as RMS (root mean square).
G
p
. This value varies according to the waveform of the signal,
G
RMS
2
=1.41. In presence of distortions the Crest Factor
EN - 5
HT37 - HT39
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 paragraph 6.3 are included.
Should you have to return back the instrument for any reason please follow the
instructions mentioned in paragraph 7.
3.2. SUPPLY VOLTAGE
The instrument is powered by batteries mod. 9V NEDA1604, JIS006P, IEC6F22 included
in the packaging. Battery life is approx. 300 hours.
When batteries are low the symbol "
instructions indicated in paragraph 5.2.
3.3. CALIBRATION
The instrument complies with the technical specifications contained in this manual and
such compliance is guaranteed for 12 months.
3.4. STORAGE
After a period of storage in extreme environmental conditions exceeding the limits
mentioned in paragraph 6.2.1 let the instrument resume normal operating conditions
before using it.
" is displayed. To replace/insert batteries follow the
EN - 6
HT37 - HT39
4. OPERATING INSTRUCTIONS
4.1. INSTRUMENT DESCRIPTION
4.1.1. Front panel
LEGEND:
1. LCD display.
2. Functions keys (RS-232
and
keys for HT39
only).
3. Rotary selector.
4. A input for AC/DC
current measurements.
5.
HzVΩµA input for
other measurements.
6. COM input.
Fig. 1: Instrument description
EN - 7
HT37 - HT39
4.2. FUNCTION KEYS
When pressing a key, the corresponding symbol is displayed with a beep.
To resume default state turn the selector on another function.
4.2.1. MIN MAX
By pressing MIN MAX key, maximum and minimum values are measured. Both values are
stored and can be recalled by pressing the same key. The symbol corresponding to the
desired function is displayed: “MAX” for maximum value, “MIN” for minimum value. MIN
MAX key is disabled when HOLD function is active. To exit this function keep MIN MAX
key pressed for at least 1 second or rotate the selector to another position.
4.2.2. PEAK/∆
This key have the double function of measuring max/min peak values (active for ∼V and
∼A positions of rotary selector) and performing relative measurements (∆REL) for any
position of rotary selector other than ∼V and ∼A.
Press cyclically PEAK/∆ to measure and save peak values. “P
MAX
” and “P
MIN
” symbols on
the display correspond to Maximum Peak and Minimum Peak values respectively which
are continuously updated by the meter. By keeping pressed PEAK/∆ key for at least 3
seconds, “CAL” symbol appears on the display and the meter performs an auto calibration
permitting a higher accuracy on peak measurements.
To exit this function keep pressed PEAK/∆ for at least one second or rotate the selector on
another position.
By pressing PEAK/∆ key, the relative measurement is activated: the meter saves the
(offset) value on the display and the “∆REL” symbol is shown. The following measurement
will be referred to this offset value. By pressing again PEAK/∆ key the offset value is
shown and the “∆REL” symbol is blinking.
To exit this function keep pressed PEAK/∆ for at least one second or rotate the selector on
another position.
4.2.3. RANGE
By pressing RANGE key the manual mode is activated and the “RANGE” symbol is
displayed. Press RANGE cyclically to change the measuring range and fix the decimal
point on the display. RANGE is disabled on positions
/ , ∼A and A performing
measurements in Autorange.
Keeping press for at least 1 second RANGE key or moving the rotary switch to exit from
this mode.
4.2.4. HOLD
By pressing HOLD the measured value is frozen on the display where the symbol “HOLD”
appears. To exit this function press HOLD again or rotate the selector to another position.
EN - 8
HT37 - HT39
4.2.5. RS-232 for connection to PC (HT39 only)
HT39 can be connected to a PC by means of the optional software package mod. SW39
(software + serial cable). To connect HT39 to a PC proceed as follows:
Fig. 2: Connection of HT39 to a PC
1. Insert the connector of the serial cable in the serial input on the upper side of the meter
(see Fig. 2).
2. Insert the 9 pin connector plug in the PC serial port (COM).
3. Press RS-232 key to activate the serial connection. “RS232” symbol is displayed and
the “APO” symbol disappears (the AutoPowerOFF function is disabled).
4. Run SW39 software and press “Connect” key to activate the real-time visualization of
parameters values between the meter and the PC. For any detail please refer to the
Help-on-line of SW39.
5. Press RS-232 key to exit the RS232 mode.
4.2.6. BACKLIGHT
By pressing
key it’s possible to activate/disable the backlight function on the display.
(HT39 only)
This function is available on each position of the rotary selector.
4.2.7. Disable AutoPowerOFF
When the meter is to be used for long periods of time, the operator might want to disable
the AutoPowerOFF function. Once the AutoPowerOFF function is disabled the meter stays
on continuously. To disable the AutoPowerOFF function:
• Switch OFF the meter.
• Turn ON the meter keeping pressed MIN MAX, PEAK/∆ and RANGE keys.
The AutoPowerOFF function is automatically activated when turning ON again the meter.
EN - 9
HT37 - HT39
4.3. MEASUREMENTS
4.3.1. DC Voltage measurement
Maximum input for DC voltage is 1000V. Do not attempt to take any voltage
measurement that exceeds the limits. Exceeding the limits could cause
electrical shock and damage the multimeter.
CAUTION
Fig. 3: DC Voltage measurement
1. Turn the selector on
2. Insert the test leads into the jacks, the red plug into
V.
HzVΩµA jack and the black plug
into COM jack (Fig. 3).
3. Connect the red and black test leads to the positive and negative poles of the circuit
under test respectively. The voltage value will be displayed with automatic detection of
the range.
4. Press RANGE key to activate the manual mode; the “AUTO” symbol disappears from
display. Press cyclically RANGE to change the position of the decimal point on the
display. To activate the Autorange function keep pressed RANGE for at least 1 second.
5. The message "OL" means that the voltage exceeds the measuring limits. In this case
disconnect the test leads from the circuit under test to avoid damaging the instrument
or endanger your own safety.
6. The symbol "-" on the display means that voltage has opposite direction than shown in
Fig. 3.
7. For minimum and maximum value measurement, HOLD and Relative ∆REL functions
please refer to paragraph 4.2.
EN - 10
HT37 - HT39
4.3.2. AC Voltage measurement
Maximum input for AC voltage is 750V rms. Do not attempt to take any
voltage measurement exceeding such limit to avoid the risk of electrical
shock and damages to the instrument.
CAUTION
Fig. 4: AC Voltage measurement
1. Turn the selector on ∼V.
2. Insert the test leads into the jacks, the red plug into
HzVΩµA jack and the black plug
into COM jack (Fig. 4).
3. Connect the red and black test leads to the positive and negative poles of the circuit
under test respectively. The voltage value will be displayed with automatic detection of
the range.
4. Press RANGE key to activate the manual mode; the “AUTO” symbol disappears from
display. Press cyclically RANGE to change the position of the decimal point on the
display. To activate the Autorange function keep pressed RANGE for at least 1 second.
5. The message "OL" means that the voltage exceeds the measuring limits. In this case
disconnect the test leads from the circuit under test to avoid damaging the instrument
or endanger your own safety.
6. For minimum and maximum value measurement, HOLD function and Peak
measurement please refer to paragraph 4.2.
EN - 11
HT37 - HT39
4.3.3. DC Current measurement
Maximum input for DC current is 10A. Do not attempt to take any current
measurement exceeding such limit to avoid the risk of electrical shock and
damages to the instrument.
CAUTION
Fig. 5: DC Current measurement
1. Switch OFF the circuit under test.
2. Turn the selector on
A.
3. Insert the red test lead into A jack and the black plug into COM jack (Fig. 5).
4. Connect red and black plugs in series with the circuit under test respecting the polarity
and current flow indicated in Fig. 5.
5. Power the circuit under test. The current value is displayed.
6. The message "OL" means that the current exceeds the measuring limits. In this case
disconnect the test leads from the circuit under test to avoid damaging the instrument
or endanger your own safety.
7. If the measured value is lower than 4mA, to get a better resolution:
• Switch off the circuit under test.
• Turn the selector on
• Remove the red test lead from A jack, and insert it into
µA.
HzVΩµA jack.
• Power the circuit under test.
8. The symbol "-" on the display means that current has opposite direction than shown in
Fig. 5. Press RANGE key for manual range only active in
µA position of the rotary
selector.
9. For minimum and maximum value measurement, HOLD and Relative ∆REL functions
please refer to paragraph 4.2.
EN - 12
HT37 - HT39
4.3.4. AC Current Measurement
Maximum input for AC current is 10A. Do not attempt to take any current
measurement exceeding such limit to avoid the risk of electrical shock and
damages to the instrument.
CAUTION
Fig. 6: AC Current measurement
1. Switch OFF the circuit under test.
2. Turn the selector on ∼A.
3. Insert the test leads into the jacks, the red plug into A jack and the black plug into COM
jack (Fig. 6).
4. Connect red and black plugs in series with the circuit under test as indicated in Fig. 6.
5. Power the circuit under test. The current value is displayed.
6. The message "OL" means that the voltage exceeds the measuring limits. In this case
disconnect the test leads from the circuit under test to avoid damaging the instrument
or endanger your own safety.
7. For minimum and maximum value measurement, HOLD function and Peak
measurement please refer to paragraph 4.2.
EN - 13
HT37 - HT39
4.3.5. Frequency measurement
Maximum input for AC voltage is 750V rms. Do not attempt to take any
voltage measurement exceeding such limit to avoid the risk of electrical
shock and damages to the instrument.
CAUTION
Fig. 7: Frequency measurement
1. Turn the selector on Hz.
2. Insert the test leads into the jacks, the red plug into
HzVΩµA jack and the black plug
into COM jack (Fig. 7).
3. Connect the red and black test leads to the positive and negative poles of the circuit
under test respectively. The voltage value will be displayed with automatic detection of
the range.
4. Press RANGE key to activate the manual mode; the “AUTO” symbol disappears from
display. Press cyclically RANGE to change the position of the decimal point on the
display. To activate the Autorange function keep pressed RANGE for at least 1 second.
5. The message "OL" means that the frequency exceeds the measuring limits. In this
case disconnect the test leads from the circuit under test to avoid damaging the
instrument or endanger your own safety.
6. For minimum and maximum value measurement, HOLD and Relative ∆REL functions
please refer to paragraph 4.2.
EN - 14
HT37 - HT39
4.3.6. Resistance measurement
Before taking resistance measurements in circuit remove power from the
circuit being tested and discharge all capacitors.
CAUTION
Fig. 8: Resistance measurement
1. Turn the selector on Ω.
2. Insert the test leads into the jacks, the red plug into
HzVΩµA jack and the black plug
into COM jack (Fig. 8).
3. Connect the red and black test leads to the circuit under test, the resistance value will
be displayed with automatic detection of the range.
4. Press RANGE key to activate the manual mode; the “AUTO” symbol disappears from
display. Press cyclically RANGE to change the position of the decimal point on the
display. To activate the Autorange function keep pressed RANGE for at least 1 second.
5. The message "OL" means that the resistance exceeds the measuring limits. In this
case disconnect the test leads from the circuit under test to avoid damaging the
instrument or endanger your own safety.
6. For minimum and maximum value measurement, HOLD and Relative ∆REL functions
please refer to paragraph 4.2.
EN - 15
HT37 - HT39
4.3.7. Diode test and continuity test
Before taking resistance measurements in circuit remove power from the
circuit being tested and discharge all capacitors.
CAUTION
Fig. 9: Diode test and test continuity
1. Turn the selector on
/
.
2. Insert the test leads into the jacks, the red plug into HzVΩµA jack and the black plug
into COM jack (Fig. 9).
3. Connect the red lead to the positive side (anode) of the diode and the black lead to the
negative side (cathode). The meter displays the diode voltage to approximately 0.4 ~
0.9V for good junction.
4. Reverse the connections and measure the voltage across the diode again. The
message “OL" on the display corresponds to a correct junction.
5. The continuity test is always active and the test is performed using the test leads in the
same way of resistance measurement (refer to paragraph 4.3.6). The buzzer is on for
resistance values <450Ω.
6. For minimum and maximum value measurement, HOLD and Relative ∆REL functions
please refer to paragraph 4.2.
EN - 16
HT37 - HT39
4.3.8. Capacitance measurement
Before taking any in circuit or capacitance measurement, remove power
from the circuit being tested and discharge all capacitors. Use the short test
lead pair for measurement in order to reduce the stray capacitance. Before
connecting the test capacitor, note the display, which may show a reading
other than zero whenever the range is changed. Subtract this offset reading
from the test result of a capacitor to obtain the true value. Connect the test
capacitor to the input clamps noting the polarity connections when required.
CAUTION
Fig. 10: Capacitance measurement
1. Turn the selector on
2. Insert the test leads into the jacks, the red plug into
.
HzVΩµA jack and the black plug
into COM jack (Fig. 10).
3. Connect the test leads to the capacitor terminals taking care of the shown polarity. The
capacitance value will be displayed with automatic detection of the range.
4. Press RANGE key to activate the manual mode; the “AUTO” symbol disappears from
display. Press cyclically RANGE to change the position of the decimal point on the
display. To activate the Autorange function keep pressed RANGE for at least 1 second.
5. The message "OL" means that the capacitance exceeds the measuring limits. In this
case disconnect the test leads from the circuit under test to avoid damaging the
instrument or endanger your own safety.
6. For minimum and maximum value measurement, HOLD and Relative ∆REL functions
please refer to paragraph 4.2.
EN - 17
HT37 - HT39
5. MAINTENANCE
5.1. GENERAL INFORMATION
1. 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.
2. Do not expose it to high temperatures or humidity or direct sunlight.
3. 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.
5.2. BATTERY REPLACEMENT
When the symbol "
Before replacing batteries disconnect the test leads from any energized
circuits to avoid electrical shocks.
" is displayed, batteries need replacement.
CAUTION
LEGEND:
1. Turn OFF the meter and disconnect
the test leads from the input
terminals.
2. Remove the protective holster from
the meter.
3. Unscrew the battery cover and
remove the battery.
4. Insert a new battery of the same
type (9V NEDA1604, JIS006P,
IEC6F22) observing the proper
polarity, re-screw the battery cover
and reposition the protective holster.
Fig. 11: Battery replacement
EN - 18
HT37 - HT39
5.3. FUSE REPLACEMENT
Before replacing fuses, disconnect test leads from any energized circuit to
avoid electrical shock.
CAUTION
LEGEND:
1. Turn OFF the meter and disconnect
the test leads from the input
terminals.
2. Remove the protective holster from
the meter.
3. Unscrew the battery cover and
remove the battery.
4. Remove the defective fuse and
install a new fuse of the same size
and rating (fast type 10A/1000V).
Make sure the new fuse is centered
in the fuse holder. Re-screw the
battery cover and reposition the
protective holster.
Fig. 12: Fuse replacement
5.4. CLEANING
To clean the instrument use a soft dry cloth. Never use a wet cloth, solvents or water.
5.5. END OF LIFE
CAUTION: this symbol indicates that equipment and its accessories shall be
subject to a separate collection and correct disposal.
EN - 19
HT37 - HT39
6. TECHNICAL SPECIFICATIONS
6.1. TECHNICAL FEATURES
The accuracy is indicated as [% of reading + number of digits]. It is referred to the
following environmental conditions: temperature 23°C ± 5°C, relative humidity < 80%.
DC Voltage
Range Resolution Accuracy Input impedance Overload protection
400.0mV 0.1mV
4.000V 0.001V
40.00V 0.01V
400.0V 0.1V
1000V 1V
±(0.5%rdg+2dgt)
10MΩ //
less of 100pF
AC TRMS Voltage
Range Resolution
400.0mV 0.1mV Not specified
4.000V 0.001V
40.00V 0.01V
400.0V 0.1V
750V 1V
Accuracy
(50 ÷ 500Hz)
±(1.3%rdg+5dgt)
(50 ÷ 300Hz)
±(1.2%rdg+5dgt)
(50 ÷ 500Hz)
Input impedance Overload protection
10MΩ //
less of 100pF
DC Current
Range Resolution Accuracy Output voltage Overload protection
400.0µA 0.1µA
4000µA 1µA
±(1.0%rdg+2dgt)
10.00A 10mA
<5mV/µA
2V max
AC TRMS Current (Autorange)
Range Resolution
10.00A 10mA
Accuracy
(50 ÷ 500Hz)
±(1.5%rdg+5dgt)
Output voltage Overload protection
2V max
Frequency
Range Resolution Accuracy
4000Hz 1Hz
40.00kHz 0.01kHz
400.0kHz 0.1kHz
4.000MHz 0.001MHz
40.00MHz 0.01MHz
Minimum pulse width: 25ns
Duty cycle limit: >30% e <70%
±(0.01%rdg+1dgt)
Sensitivity Overload protection
>1.5VACrms
<5VACrms
>2VACrms
<5VACrms
1000VDC
750VACrms
1000VDC
750VACrms
600Vrms
Fast fuse
10A / 1000V
600Vrms
600Vrms
EN - 20
HT37 - HT39
Resistance
Range Resolution Accuracy Open voltage Overload protection
400.0Ω 0.1Ω ±(1.0%rdg+5dgt)
4.000kΩ 0.001kΩ
40.00kΩ 0.01kΩ
400.0kΩ 0.1kΩ
4.000MΩ 0.001MΩ ±(1.0%rdg+2dgt)
40.00MΩ 0.01MΩ ±(1.5%rdg+5dgt)
±(0.7%rdg+2dgt)
1.3V 600V rms
Diode test
Range Resolution
10mV
Accuracy
(0.4 ÷ 0.8V)
±(1.5%rdg+5dgt)
Test
current
1.5mA <3V 600V rms
Open
voltage
Overload protection
Continuity test
Range Buzzer Overload protection
R<450Ω
600V rms
Capacitance
Range Resolution Accuracy Overload protection
4.000nF 0.001nF
40.00nF 0.01nF
400.0nF 0.1nF
4.000µF 0.001µF
40.00µF 0.01µF
400.0µF 0.1µF
4.000mF 0.001mF
40.00mF 0.01mF
±(3.0%rdg+10dgt)
±(2.0%rdg+8gt)
±(5.0%rdg+20dgt)
600V rms
6.1.1. Electrical specifications
Conversion: TRMS
Measuring rate: 1.5 times per second
Temperature coefficient: 0.15×(accuracy)/°C (<18°C and >28°C)
NMRR Normal Mode Rejection Ratio: > 50dB for DC parameters and 50/60Hz
CMRR Common Mode Rejection Ratio: >100dB from DC up to 60Hz on DCV
> 60dB from DC up to 60Hz on ACV
6.1.2. Safety
The instrument complies with: EN 61010-1
Insulation: Class 2, double insulation
Pollution degree: 2
Overvoltage category: CAT IV 600V, CAT III 1000V (V/Ω/µA)
CAT IV 500V (A)
Max height: 2000m
EN - 21
HT37 - HT39
6.1.3. General data
Mechanical characteristics
Dimensions (with holster): 164x82x44mm
Weight (including battery): About 400g
Power supply
Battery type: 9V NEDA1604, JIS006P, IEC6F22
Low battery indication: "
" is displayed when battery voltage is too low
Battery life: About 300 hours
AutoPowerOFF: 30 minutes after last pressure on keys or rotation
of selector
Display
Specifications: 4 LCD with max. reading 4000 counts + symbol,
decimal point and bargraph
Over range indication: “OL” or “-OL”
6.2. ENVIRONMENT
6.2.1. Environmental conditions
Reference temperature: 23 ± 5°C
Working temperature: 0 ÷ 30°C
Relative humidity: <80%RH
Storage temperature: -20 ÷ 60°C
Storage humidity: <80%RH
6.2.2. EMC and LVD
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
Standard accessories
• HT37 or HT39 meter.
• Test leads.
• Battery (fitted).
• Instruction manual.
Optional accessories
•
Carrying bag – Code B80.
•
Software + serial cable (only HT39) – Code SW39.
EN - 22
HT37 - HT39
7. SERVICE
7.1. WARRANTY CONDITIONS
This instrument is guaranteed for one year 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 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.
• Use not provided by the instrument's specifications or in the instruction manual.
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.
7.2. SERVICE
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.
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.
EN - 23
Loading...