Hongda USA HDT20A User manual

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HDT20A HDT20B
Insulation Resistance Tester User's Manual
Safety Rules
Safety Warning
The design、manufacture and test are all up to the safety
standard IEC61010(safety demand of the electronic products), this
manual includes the safe using of the instrument and the safety
state of instrument, the warning and the safety rules that the users
must comply. Please read the manual before use.
Warning
●Please read carefully and understand this manual before using
the instrument.
●Please comply the regulation of the manual all the time, and
keep the manual for consultation.
●When using the instrument for testing, wrong operation can
result in accident and instrument damage.
●The Company reserves the right to modify the instructions, if the
instructions are to change without notice，pls understand.
The symbols on the instrument mean that in order to operate
the instrument safely, the users are supposed to refer to the relating
description in this manual.
Danger is in order to avoid the probably serious or fatal
damage in some state and operation.
Warning is in order to avoid the danger of electric-shocking.
Notice means avoiding the damage to the instrument and
accurate measuring.
Danger
●Please don't take measurement in the flammability place, the
spark maybe result in explosion.
●Please don't operate the instrument if it is wet of the instrument
surface or of the user's hand.
●When testing voltage, it probably result in person injury
because of the short circuit of the metal part and the testing lead.
●Please don't exceed the maximum scope of the allowable range.
●Don't open the battery cover when testing.
●When taking the insulated measurement, please don't touch the
circuitry under test.
Warning
●If there is abnormity from the instrument, please stop using.
For example: the instrument dilapidation or metal part exposure.
●Please don't rotate the Function/Selection switch when the
testing lead is inserted into the instrument and connected to the
circuitry for testing.
●Please don't install any substituting parts to the instrument or
carry on any unauthorized modification, instruments are sent back
to the Hongda Company when maintaining.
●Please don't replace the battery when the instrument is in the
state of humidity.
●Please sure the connection is fastness of all the testing
interfaces between the testing lead and the instrument.
●Please sure the instrument is turned off when opening the
battery cover.
Notice
●Before test, please sure the voltage selector switch is on the
proper location.
●After test, please set the function switch to the range "OFF". If
it is available for a long time, please take out the battery for storage
●Please don't put the instrument in the place of high
temperature、humidity、dew and strong light for a long time.
●Please use the humid cloth or detergent to clean the instrument
case. Don't use the friction material or solvent.
●If the instrument is wet, please make it dry then storage.
Symbol
The probability of electric-shocking
The instrument has double insulation or reinforcing insulation
Important operation(referring to the manual)
1.Preface
1.1 Thanks for use our products, you will get the
comprehensive technology support and service from our company.
1.2This manual is used for HDT20A/HDT20B insulation
resistance tester.
1.3 Before using the product, please read the manual
carefully and keep it well for reference.
1.4 The product is for high-voltage electric equipment tester,
please accord to the manual description to operate.And comply
strictly to the Nation's related regulations. For inappropriate
operation, it will probably result in equipment damage or person
safety danger.
1.5 Please consult our company when there is any question
as you read the manual or use the instrument.
2.Characteristics
2.1 HDT20A HDT20B is a electron controlled minitype
instrument, thereinto, the high voltage insulation resistance tester
has three insulation resistance for voltage test.
2.2 The design is up to the following safety standard:
IEC 1010
89/336/EEC(electromagnetism compatibility, Nov, 1992, EMC)
P73/23/EEC(product safety regulation: Nov, 6th, 1979,
low-voltage regulation: Feb,19th, 1973)
2.3 Automatically release voltage function:
2.4 Be used for the insulation resistance of all kinds of
electron equipment and insulation material, such as transformer、
generator、 cable、 switch、 electric equipment and so on. Be used for
the maintenance、test and check of all the series of electric
equipment.
2.5 Rated voltage variable
HDT20A-- Rated voltage can be switched among 250V, 500V,
1000V by knob switch.
HDT20B-- Rated voltage can be switched among 1000V,
2500V by knob switch.
2.6 High voltage indication
There is the LED in the instrument(HV ON) indicating the high
voltage work state.
2.7 Low battery indication.
2.8 Battery drive, removing the operation of hand-cranked
generator.
2.9 3 1/2 digital display, reading clearly.
2.10 The measurement range for HDT20A is 0.1MΩ～1999M

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Ω. The measurement range for HDT20B is 10MΩ～19.99GΩ.
2.11 Convenient operating and taking.
2.12 Strong carrying capability, output short circuit current is >
1.0 mA.
2.13 Complete protecting circuitry, in case of voltage
counterattack and output short circuit protection.
2.14 Can test AC Voltage 1V-750V, the frequency of AC
Voltage is 40Hz-400Hz.
2.15 International fashion design, dustproof and dampproof,
can be applied to outside operation.
3.Technic specifications
Test condition: test temperature/humidity 23±5℃/45～75％
RH;
Low battery voltage indication;
Insulation resistance:≥500MΩ(1000V);
Voltage withstand:AC 2KV 50Hz 1minute;
Operation temperature and humidity:0 ℃~40 ℃/Relative
humidity 85% or less;
This manual is just applied to this instrument, our company is
entitled to modify it.
HDT20A technic specifications
Basic Function
Range
Accuracy
Output Voltage
250V/500V/1000V
±10%
Output Current
250V(R=250kΩ)1mA
±10%
500V(R=500kΩ)1mA
1000V(R=1MΩ)1mA
200MΩ
250V:0.1MΩ-20MΩ
±（4%±2）
500V:0.1MΩ-50MΩ
1000V:0.1MΩ-100MΩ
2000MΩ
250V:20MΩ-500MΩ
±（4%±2）
500V:50MΩ-1000MΩ
1000V:100MΩ-2000MΩ
Short circuit
current
≤1.8mA
central value
resistance
250V/500V:2MΩ
1000V:5MΩ
ACV
750V
±（1%+6）
AC750V input impedance：1MΩ。
AC750V frequency response：（50～200）Hz
The median resistance value : Ensure measuring voltage on both
ends of less than 90% of the nominal value test voltage under
the resistance measurement of threshold
HDT20B technic specifications
Basic Function
Range
Accuracy
Output Voltage
500V/1000V/2500V
±10%
Output Current
≥100MΩ
Short circuit
current
＞1.0mA
2GΩ
500V:.010GΩ-1.999GΩ
±10%
1000V:.010GΩ-1.999GΩ
2500V:.010GΩ-1.999GΩ
20GΩ
500V:0.01GΩ-19.99GΩ
±10%
1000V:0.01GΩ-19.99GΩ
2500V:0.01GΩ-19.99GΩ
ACV
750V
±（0.1% +6）
AC750V input impedance：1MΩ。
AC750V frequency response：（50～200）Hz
4.Appearance
1. Line terminal L
2. Shield terminal G, the end terminal ofACV measurement
3. The positive terminal of the ACV measurement
4. Earth terminal E
5. Backlight button
6. Range switch button
7. High-volt startup button
8. External power jack
9. Instrument belt hole
10. High voltage indicator
1 1 . Rotary switch
12. Power button
13. 3 1/2 digit display screen
5.Safety notice
5.1 Before use, please read the manual carefully, and comply to
its step, operating accordingly.
5.2 Please don't use the accessories not being supplied by the
original company in case of danger.
5.3 While measuring, the terminal E、L has DC high voltage
output, non-human contact in case of electric shock.
5.4 In order to avoid the error resulted by the insulation
leakiness of the test stick, the test stick connected to the terminal L
is supposed to hang in the air as possible as it could, can't touch
with the outside object.
5.5 When the insulation resistance value of the tested object is
very high, and there is the serious word jump phenomenon, then
please connect the shield terminal G. For example: measuring the
cable core and cable shell, besides connecting the two ends of the
tested object to the terminal E and L separately, you are also
supposed to connect the inner insulation of the cable core or cable
shell to the shield terminal G, in order to avoid the measuring error
resulted by the surface leakiness. Further more, you can also use
the shielding box. That is to say just put the tested object into the
metal shielding box, then connect the shielding box to the
instrument shielding terminal G.
5.6 When the measurement is finished, then remove the
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connecting line.
5.7 Don't use or have the storage in the place of sun、high
temperature、humidity etc.
5.8 The short circuit time of the testing end should be less than
60s.
5.9 The continuous testing time should be less than 3 hours one
time.
6.Work theory
The high voltage part of the instrument is applied with the
Pulse Width Modulate(PWM), via the inner double voltage output
cathode DC high voltage, with the characteristic of energy saving,
good voltage linearity, stabilization and small ripple coefficient.
The high voltage produced by the instrument line terminal
goes to the instrument earth terminal via the load resistance Rx,
then transformation via V/I to display the digit.
7.Testing
Danger
●Before testing, please sure there is no charge existing in the
tested circuitry that the high voltage instrument is connected
with.
●Please put on a pair of the high voltage insulation gloves.
●If the battery cover is open, please don't carry on any
measurement.
7.1 testing end connection
Insert the plug of the testing line with the testing stick into the L
terminal socket of the instrument, then insert the plug of the testing
line with the testing clip to the E terminal socket of the instrument
and connect well separately.
7.2 testing connection
The connection of terminal E plug(black test lead with the big
testing clip) is for the Earth, connect the testing clip to one side of
the item ; the connection of terminal L plug(red test lead) is
circuitry line, can connect the testing clip to the other side of the
item ; the connection of terminal G plug is shielding line, and is
connected to the surface of the tested object to avoid the surface
leakiness which will influence the testing impedance. Connect the
testing clip to one end of the tested object, and the small clip of the
test lead to the surface of the tested object to avoid the current
leakiness.(Picture A and B)
7.3 Rated voltage selection
Select the rated voltage according to the test requirements:
HDT20Acan choose 250V 500V 1000V
HDT20B can choose 500V 1000V 2500 V
7.4 Testing operation
Please pay attention to safety operation:
Connect the test lead of the test stick to one end of the tested
object, press down the high voltage startup button [TEST], then the
red indication light HV ON turns on to show that the high voltage
output gets through. When the high voltage indicator is on, it
means the instrument work normally. If it is off, it shows maybe
the battery is low voltage or battery connection is abnormally.
When the measurement is begun, there is reading on the meter
header which is the insulation resistance value of the tested object
under the current voltage.
For the HDT20A, when the test value is less than 200M
Ω,suggest pressing the “”button, using 200MΩrange
can make the readings more accurate. For the HDT20B, when the
test value is less than 2GΩ,suggest pressing the “”
button, using 2GΩrange can make the readings more accurate.
When the testing is out of range (the digit only display “1”), you
can check the “”or “”button is in the raised
state or not, if not you can press it to let it in the raised state; if yes
show the measured value of insulation resistance measurement is
beyond the scope of this instrument, pls consider using a higher
resistance of tester.
If you need more convenient readings, you can press the
“HOLD, LIGHT”button, the display digit will be locked and
backlight is on for easy reading. Press that button again to restore
the normal measurement state and the backlight is off.
7.5 Backlight
Press button, backlight is on; press the button again, the
backlight is off.
7.6 Power off
After finish the measurement, press down the high voltage
button [TEST], HV ON red indicator turns off slowly, showing the
high voltage output has disconnected. Set the switch to the position
[OFF], there is no display on the LCD. For the capacitive load, you
should completely release the residual charge in the tested object to
avoid the residual charge release electricity to injury people.
8. AC Voltage Test
8.1 Using the rotary switch select the “ACV”position
8.2 Insert the red test lead into the “ACV”jack, insert the black
test lead into the “G”input jack
8.3 Contact the two test leads with the both ends of the voltage
to be measured, then the digital display show the AC voltage in
volt.
Note:
1. The measured voltage can’t exceed 750V AC RMS, the
frequency of the ACV is 40Hz to 400Hz. If exceed this
frequency range, the data errors will exceed the technical
specifications of this instrument.
2. For the earth voltage to be measured at the both ends can’t
exceed 750V AC RMS, otherwise will meet the danger of
electric shock.
3. AC voltage test, don’t need to transfer the high voltage
and range, so at that time the “TEST”and
“”button are disabled.
9.Battery replacement
If there is the symbol " " on the LCD, it indicates low battery,
please replace the battery.
Before replacing the battery, please sure the testing connection
has been disconnected and power is cut off.

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9.1 Stop all the testing work, and remove the testing line from
the tested object.
9.2 Set the switch to the ”OFF”position.
9.3 Remove the testing line from the instrument.
9.4 Take off the battery cover on the back of the instrument.
9.5 Put into 6 pieces batteries, the model is LR6 or
UM-3.(Please pay attention to the battery polarity)
9.6 Put on the battery cover.
10.Storage
10.1 Set the switch to the “OFF”position.
10.2 When the instrument is available for a long time, please
take off the battery to avoid the electrolyte discharge resulting in
rust.
10.3 Please keep the case clean.
10.4 instrument storage:
Storage temperature:-10℃~ +50℃
Storage relative humidity: 90%RH
The place need no dust, no causticity gas and well-ventilated.
11 Accessory
HDT20A: one plastic cover, a pair of test lead(with clip), one
manual and one warranty card.
HDT20B: one plastic cover, a pair of test lead (with clip), one
manual ,one warranty card and one shielding line.