Unit UT516B User manual

P/N:110401108715X
UT516B
Insulation
Resistance
Tester
User Manual

Preface
Thank you for purchasing the new UT516B insulation resistance tester. In order to use this product safely and
correctly, please read this manual thoroughly, especially the Safety Instructions part.
After reading this manual, it is recommended to keep the manual at an easily accessible place, preferably close
to the device, for future reference.
Limited Warranty and Liability
Uni-Trend guarantees that the product is free from any defect in material and workmanship within one year from
the purchase date. This warranty does not apply to damages caused by accident, negligence, misuse, modification,
contamination or improper handling. The dealer shall not be entitled to give any other warranty on behalf of
Uni-Trend. If you need warranty service within the warranty period, please contact your seller directly.
Uni-Trend will not be responsible for any special, indirect, incidental or subsequent damage or loss caused by
using this device.
UT516B User Manual
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3 4
1. Overview
The UT516B is a digital high voltage insulation resistance tester with 6 ranges: 500V, 1000V, 2500V, 5000V,
10000V and 12000V. Fine adjustment of voltage with 10% step at each range (except 12000V) is available.
Test data can be saved in the tester memory and transferred to a PC via the dedicated USB cable, or be
transferred to a PC in real time.
2. Features
Designed to meet IEC61010-1, CAT IV 600V and Pollution Degree 2 safety standards
For insulation resistance test, max test voltage: 12kV, max test resistance: 10TΩ, max short-circuit
current: 5mA
Automatic display of Dielectric Absorption Ratio (DAR) and Polarization Index (PI)
Large memory for saving up to 999 sets of test data
Dual power supply: Dedicated power adapter (DC15V, 1A) or 10 pcs 1.5V alkaline batteries (Lr14)
5.1-inch industrial display (320×240 pixels)
Simultaneous display of insulation resistance and leakage current values in the test
PC software for data analysis
Green light indication for POWER button and red light warning for TEST button
Auto discharge function: When insulation resistance like a capacitive load is tested, electric charges
stored in capacitive circuits are automatically discharged after testing. Discharge progress can be displayed.
Backlight Function: To facilitate working at dimly illuminated location or at nighttime
UT516B User Manual UT516B User Manual
1. Overview ------------------------------------------------------------------------------------------------------------------- 4
2. Features -------------------------------------------------------------------------------------------------------------------- 4
3. Accessories ---------------------------------------------------------------------------------------------------------------- 5
4. Safety Instructions ------------------------------------------------------------------------------------------------------- 5
5. Electrical Symbols ------------------------------------------------------------------------------------------------------- 7
6. External Structure -------------------------------------------------------------------------------------------------------- 8
7. Indicators and Buttons -------------------------------------------------------------------------------------------------- 9
8. Operating Instructions ------------------------------------------------------------------------------------------------- 15
9. Specifications ------------------------------------------------------------------------------------------------------------ 31
10. Communication Function (Including Software) ------------------------------------------------------------------ 35
11. Use of Power Adapter -------------------------------------------------------------------------------------------------- 36
12. Test Probe Metal Parts and Replacement ------------------------------------------------------------------------ 37
13. Maintenance ------------------------------------------------------------------------------------------------------------- 38
Table of Contents

5 6
3. Accessories
Open the package box and take out the tester. Please double check whether the following items are missing
or damaged.
a) User manual ------------------------------------------------------ 1 pc
b) Test leads (red, black, green, 1 each) ---------------------- 3 pcs
c) USB cable --------------------------------------------------------- 1 pc
d) Dedicated power adapter -------------------------------------- 1 pc
e) 1.5V alkaline batteries (LR14) -------------------------------- 10 pcs
If any of the above is missing or damaged, please contact your supplier immediately.
4. Safety Instructions
The tester is designed, manufactured and tested according to IEC61010 safety standards (safety requirements
for electronic measuring apparatus). It conforms to double insulation, CAT III 1000V and CAT IV 600V safety
standards. This manual contains warning information and safety regulations. Please read them carefully and
observe them strictly to ensure the safety of the user and tester.
Warning
The UT516B is a 12kV digital high voltage insulation resistance tester. Please read the Safety
Instructions in detail.
The tester outputs high voltage. Please read and understand the Operating Instructions thoroughly before use.
Keep the manual at an easily accessible place to enable quick reference whenever necessary.
Use the tester only as specified.
Please strictly follow all the instructions, or it may cause damage to the tester and user!
Please wear insulated gloves before use.
Do not measure in circuits with voltage above AC 750V or DC 1000V.
Do not test in flammable places. Sparks may cause an explosion.
Never use the tester if its surface or the operator's hands are wet.
Be careful not to short-circuit the metal part with the test leads when testing voltage or it may cause personal
injury.
Do not exceed the maximum allowable range during measurement.
To prevent damage to the tester from high voltage output, do not press the TEST button when the test leads
are connected to the tester.
Never open the battery cover during measurement.
Do not touch the circuit under test when measuring insulation resistance or right after measurement, otherwise
it may pose an electric shock.
Stop the test if contamination or carbonization which may impair insulation characteristics is found on the test
leads or around the terminals.
Avoid short circuit and open circuit of the test leads when measuring insulation resistance. Otherwise, the
measurement may be ceased and the light of the TEST button may go out.
Before use, please check if there is any item which is damaged or behaving abnormally. If any abnormal item
(such as bare test lead, damaged tester housing, broken LCD, etc.) is found, or if the tester is considered to be
malfunctioning, please do not use the tester.
Do not use the tester if the battery cover is not covered up, or it will pose a shock hazard!
When using the tester, keep fingers behind the finger guards on the test leads, and do not touch exposed
wires, connectors or alligator clips to prevent electric shock.
Select correct output voltage before measurement. It is forbidden to change the voltage during measurement
to avoid damage to the tester.
When the “ ” symbol appears on the LCD, please replace the batteries in time to ensure measurement
accuracy. If the tester is not in use for a long time, please remove the batteries. Make sure the tester is turned
off before opening the battery cover.
Do not change the internal circuit of the tester to avoid damage to the tester and user!
Do not use or store the tester in high temperature, high humidity, flammable, explosive or strong magnetic
field environments.
Clean the tester housing with a soft cloth and mild detergent. Do not use abrasives or solvents!
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5. Electrical Symbols
Description
Equipment protected throughout by DOUBLE
INSULATION or REINFORCED INSULATION
Earth (ground) Terminal
Warning or Caution
Alternating current
Direct current
Low battery
Caution, possibility of electric shock
Symbol
6. External Structure (Picture 1)
EARTH: Input terminal
for insulation sampling
test lead
GUARD: Input terminal
for grounding guard
test lead
LINE: Input terminal for
high voltage output test
lead
LCD
Buttons on the left
Battery cover
USB port
Power adapter port
Buttons on the right
Placement area for
test leads and power
adapter
Insulation sampling
test lead (black)
Grounding guard test
lead (green)
High voltage output
test lead (red)
Dedicated power adapter
High Voltage (+) GUARD EARTH（-）
INSUL TIMING COMP DCV/
ACV
SET USB
OK
TEST
Press for > 1s
SAVE RECALL CLEAR
CURRENT
CLEAR ALL
NOTE:
Do not measure charged bodies. Disconnect all electrical connections before
measuring.
Turn off tester and remove all test leads before opening battery cover. Make
sure charged bodies are isolated from test leads before taking out batteries.
Contains 10 alkaline batteries (Lr14).
Picture 1
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9 10
USB
VDC
VAC
＋
－
>,<,=
mA/uA/nA
1
2
3
4
5
6
7
8
9
10
11
7. Indicators and Buttons
7.1 Display Indicators
0 level: Battery voltage <11.0V. Replace the batteries.
1 level: Battery voltage (11.0V~12.0V), for 500V\1000V
\2500V\5000V\10000V test
2 level: Battery voltage (12.1V~13.0V), for 500V\1000V
\2500V\5000V\10000V test
3 level: Battery voltage (13.1V~13.5V), for 500V\1000V
\2500V\5000V\10000V test
4 level: Battery voltage (13.6V~14.0V), for 500V\1000V
\2500V\5000V\10000V\12000V test
5 level: Battery voltage (>14.1V), for 500V\1000V\2500V
\5000V\10000V\12000V test
When the power adapter is used, the battery indicator
is automatically turned off.
Power adapter (15V), for 500V\1000V\2500V\5000V\
10000V\12000V test
Battery level
Power adapter
Caution, possibility
of electric shock
Analog bar
PC communication
DC voltage
AC voltage
DC voltage positive pole
DC voltage negative pole
greater than, less than, equal to
Current units
Only for insulation measurement
Comparative measurement results
High voltage output indicator
Analog bar for insulation resistance
No. Indicator Description Remark
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11 12
7.2 Buttons (Picture 2, Picture 3)
Switch to insulation measurement. The tester defaults to insulation measurement after
booting. This button also can be used to exit each setting interface.
Short press to turn on/off timing measurement. The tester defaults
to continuous measurement mode after booting.
Short press to turn on/off comparative measurement. The tester defaults
to continuous measurement mode after booting.
Switch to voltage measurement (automatic identification of AC/DC voltage)
Short press the SET button to set system functions (short press the INSUL button to exit
each setting interface):
1. Date/Time
Set or adjust the system clock to match the current time and date.
2. Timing Measurement
Set the insulation measurement countdown time (from 60s). Once the time is up, the
insulation measurement will be stopped automatically.
3. DAR Measurement
Set the DAR measurement Time 1 (range: 15s~299s; 15s by default); set the DAR
measurement Time 2 (range: 60s~599s; 60s by default).
4. PI Measurement
Set the PI measurement Time 1 (range: 1min~29min; 1min by default); set the PI
measurement Time 2 (range: 10min~59min; 10min by default).
5. Factory Reset
Restore all settings data to default values.
When modifying a parameter, move the cursor with the LEFT/RIGHT button, use the
UP/DOWN button to change the current value, select the OK or Cancel option, and
short press the OK button to confirm the modification.
Short press to turn on/off USB transmission function. When the function is on, the
LCD displays the “USB” symbol.
Picture 2
Picture 3
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Insulation measurement: Select an output voltage range upwards.
"Settings" function: Upward adjustment button
Power on/off (green light indication for the on state).
Long press (>1s) to start insulation measurement, and short press to stop.
Insulation measurement: Adjust the output voltage range downwards by 10%.
"Settings" function: Leftward adjustment button
Insulation measurement: Adjust the output voltage range upwards by 10%.
"Settings" function: Rightward adjustment button
Insulation measurement: Select an output voltage range downwards.
"Settings" function: Downward adjustment button
Insulation measurement interface: Confirm data clearing.
"Settings" interface: Confirm an option.
When measuring insulation resistance, short press the SAVE button to save the current
measurement data in the tester and “Storage Number 001/999” will be displayed in the
lower left corner of the LCD. The storage number increases progressively from 001 to 999.
After measurement, short press the RECALL button to recall the stored measurement
data and the last saved data will be displayed by default. Short press the UP/DOWN
button to scroll through other data.
Note: The high voltage output test cannot be conducted during data recalling.
Short press the RECALL button to exit the data recalling mode, and then do the test.
Short press the CLEAR CURRENT button in recalling data and “Delete the current data?”
will appear on the LCD. Short press the OK button and the current data will be cleared
immediately.
Long press the CLEAR ALL button for about 5s in recalling data and “Delete all data?”
will appear on the LCD. Short press the OK button and all data stored in the tester will
be cleared.
Note: It may take some time to clear all data if the amount of data deleted is large.
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8. Operating Instructions
8.1 Preparation for Measurement
8.1.1 Battery Voltage Check
Press the POWER button to turn on the tester and enter the insulation measurement interface without connecting
the power adapter. When the battery indicator shown at the upper left on the LCD is 0 level (“ ”), it indicates
low battery. See 7.1 Display Indicators for the corresponding battery voltage of each level. When the battery
voltage Is below the lower limit of the operating voltage, the accuracy cannot be guaranteed. No measurement
can be performed even the TEST button is pressed down. Please replace the batteries or insert the power adapter.
8.1.2 Test Lead Connection
1) Insert the red test lead into the LINE terminal, black into the EARTH terminal.
2) Insert the green test lead into the GUARD terminal (leave the GUARD terminal unconnected unless
establishing a guard is necessary).
Note: Do not insert the green or black test lead into the LINE terminal. This cannot enable measurement
and may pose an electric shock.
8.2 Basic Measurement Operation
8.2.1 Starting up
Press the POWER button to turn on the tester and the initialization interface with “UNI-T” logo will be displayed,
as shown in Picture 4.
Picture 4
The tester enters the continuous measurement state of insulation resistance by default, as shown
in Picture 5.
Picture 5
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8.2.2 Measurement without Guard Terminal
For most tests, only two test leads are used. Connect the red test probe and black alligator with the measured
object as shown in Picture 6.
8.2.3 Measurement Using Guard Terminal
When measuring the insulation resistance from the conductor to the outer sheath of a cable, there may be a
leakage current for the intermediate layer, causing measurement error. To prevent such error, connect the green
test lead directly to the leakage current winding end (as shown in Picture 7), and the leakage current portion will
not be counted in the displayed value. The reading value is only the insulation 3resistance from the conductor
to the outer sheath of the cable.
Picture 6 Picture 7
Note: Measurement using guard terminal is suitable for testing the entire circuit of a high voltage cable
containing other high voltage equipment. Connect the GUARD terminal to the leakage current electrode of the
measured object, and EARTH terminal to the green test lead. At this time, the leakage current cannot flow into
the EARTH terminal for calculation. However, for this measurement method, the insulation resistance of the
sheath (between the shielded cable and the ground) must be >1MΩ.
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8.2.4 Use of Guard Terminal in Ultra-High Resistance Test
When the tester is powered by batteries instead of the power adapter, testing for high resistance above 100GΩ
may cause measurement error. At this time, wind the green test lead which is inserted into the GUARD terminal
around the black test lead to improve the measurement accuracy, as shown in Picture 8.
After connecting the insulation resistance under test according to the above as needed, press the , , , and
buttons to set the desired output voltage range. Then long press (>1s) the TEST button to start insulation measurement.
he LCD displays the test value as shown in Picture 9.
Note: Once the insulation measurement is started, the TEST button lights up red and the LCD displays the
" " symbol.
Short press the TEST button to stop the insulation measurement. The “Discharging…” will be displayed on the LCD as
shown in Picture 10. When the discharge is completed, the test value will be displayed on the LCD again, indicating the
completion of the insulation measurement. Then remove the test leads.
Picture 10
Picture 9
存储
Green Black
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Picture 8

21 22

Note: Do not remove the test leads during discharge, otherwise the measured object will not be fully discharged
and an electric shock will be posed. If the test leads are disconnected during discharge, reconnect the test leads
to the measured object and continue the discharge. In this case, a longer discharge period is required because
the internal discharge circuit of the tester does not work and the discharge is performed by other circuits.
Pay attention to the following during the measurement process:
Danger
Do not touch the circuit under test just after finishing the measurement to prevent electric shock.
Do not touch the circuit under test or remove the test leads until the discharge is completed.
Use a high voltage detector to check the circuit under test for electrical charge.
Be sure to wear a pair of insulated gloves for high voltage operation.
Please take care to avoid electric shock during insulation resistance measurement. Once the TEST button
is pressed down, high voltage is present on the tip of test leads and on the circuit under test.
Do not use the tester if the battery cover is not covered up.
Do not make measurement in bad weather (thunder).
Make sure the measured object is not energized or charged, otherwise there is danger of electric shock or
damage to the tester.
If the battery is too low to guarantee the measurement accuracy, the measurement will be automatically
terminated. The warning shown in Picture 11 will be displayed, and will disappear after 2s. Please replace the
batteries or insert the power adapter.
Picture 11
If the measured object is charged and the voltage is above DC 36V or AC 72V, it is forbidden to measure again.
The screen will display the warning shown in Picture 12. The electrical charge needs to be removed before
continuing the measurement.
Note:
When the insulation resistance value of the device under test is unstable, the display reading may also be
unstable.
Oscillation sound may occur in the insulation resistance test, but it is not malfunction.
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Picture 12

23 24
L
E
It takes longer time to test capacitive loads, and the display readings may gradually increase or become unstable.
When the TEST button is pressed right after the completion of a test, the next test may not be performed
immediately. Wait a few seconds and press the TEST button again for measurement.
In the insulation resistance test, output of the EARTH and GUARD terminals is positive voltage (+), while
output of the LINE terminal is negative voltage (-).
Do not extend the test leads for use, or it may affect measurement accuracy or impair safety.
When measuring high resistance above 1TΩ, the Part A of the test probe indicated in the below illustration
should not be touched with the things other than the measured object. In case that such a contact is unavoidable,
use something with high insulation resistance like foamed plastic as a cushion.
In the measurement without connecting the test leads to the measured object, the over range indication,
e.g. ">10TΩ" (at 10kV, 12kV range), may not be displayed. It is likely caused in high humidity environments
due to current leaked at unexpected points other than the measured object owing to applying high voltage.
In the insulation resistance test, when short/open circuit between the LINE and EARTH (GUARD) is operated
repeatedly or the measured object is broken down by high voltage and starts arc discharge, it may not be
able to test normally due to influence of variations in the strong electric field or interference caused at
discharging energy stored in capacitors. In this case, restart the tester to test again.
The voltage monitor may indicate 10V to 500V instead of 0V when short-circuiting the red test probe and
black test lead in outputting voltage. In this case, voltage applied to the resistors mounted in the testing
circuit of the tester is included.
8.2.5 Voltage Measurement (Check of Power Failure)
Press the DCV/ACV button to switch to voltage measurement, and connect the test leads as shown in
Picture 13.
No need to press the TEST button to start voltage measurement. When the measured object is charged, the
voltage will be directly displayed on the LCD, as shown in Picture 14 or Picture 15.
The tester is equipped with AC/DC auto-detect circuit and can measure AC/DC voltage automatically. In DC
voltage measurement, when positive voltage is applied to the red test probe, positive values are displayed
on the LCD.
Picture 13
存储
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25 26
500V
1000V
2500V
5000V
10000V
12000V
50V
100V
250V
500V
1000V
400V
500V
1000V
2500V
5000V
600V
1200V
3000V
6000V
12000V
Danger
Do not measure in circuits with voltage above AC 750V or DC 1000V to avoid electric shock.
When testing high-current devices (such as power cords), test in the secondary circuit of a circuit breaker to
avoid personal injury.
In the voltage test, please pay attention to minimize the short circuit between the power cord and the metal
tip of test lead to avoid personal injury.
Do not use the tester if the battery cover is not covered up.
8.2.6 Test Settings
1) Measurement Voltage Setting
The step value and settable voltage range at each measuring range are as follows.
Range Step Min Max
N/A N/A N/A
2) Continuous Measurement
The measurement time is continuously accumulated during continuous measurement until the TEST button
pressed to stop. Insulation measurement defaults to continuous measurement mode, as shown in Picture 16.
is
Picture 16
Picture 14 Picture 15
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3) Timing Measurement
Short press the TIMING button to turn on timing measurement and the LCD will display timing measurement,
as shown in Picture 17. During timing measurement, when the set time has elapsed, the measurement will be
terminated automatically. For the set time, please refer to the description of SET button.
4) Comparative Measurement
Short press the COMP button to turn on comparative measurement (as shown in Picture 18) and the “000M” in
the “Set Value: 000MΩ” will flash. Press the UP/DOWN button to adjust the value and LEFT/RIGHT button to
adjust the carry, starting from the last flashing bit “M” by default. Press the OK button to complete the desired
set value for comparison. Then press the TEST button to start measurement.
Picture 17 Picture 18
If the measured value is greater than the set value, it will be deemed a pass, and "PASS" will be displayed on
the screen, as shown in Picture 19.
If the measured value is less than the set value, it will be deemed a fail, and "FAIL" will be displayed on the
screen, as shown in Picture 20.
Picture 19 Picture 20
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System default:
DAR=
1-min insulation resistance
30-sec insulation resistance
5) Automatic Measurement of Dielectric Absorption Ratio (DAR) and Polarization Index (PI)
When the measurement time reaches the set time of dielectric absorption ratio (DAR), the tester will
automatically calculate and display the DAR value, as shown in Picture 21.
Other time can be set in the "Settings" option to calculate the DAR value.
Picture 21
When the measurement time reaches the set time of polarization index (PI), the tester will automatically
calculate and display the PI value.
System default:
PI=
10-min insulation resistance
1-min insulation resistance
Picture 22
Other time can be set in the "Settings" option to calculate the PI value, as shown in Picture 22.
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0.50MΩ-4.99GΩ：
±(5%+5)
5.00G-49.9GΩ：
±(10%+10)
50.0GΩ- 500GΩ：
for reference only
1.00MΩ-9.99GΩ：
±(5%+5)
10.0G-99.9GΩ：
±(15%+10)
100GΩ- 1000GΩ：
for reference only
2.50MΩ-24.9GΩ：
±(5%+5)
25.0G-249GΩ：
±(15%+10)
250GΩ- 2.5TΩ：
for reference only
5.00MΩ-49.9GΩ：
±(5%+5)
50G-499GΩ：
±(15%+20)
500GΩ- 5.0TΩ：
for reference only
10.0MΩ-99.9GΩ：
±(10%+10)
100G-999GΩ：
±(20%+20)
1000GΩ- 10TΩ：
for reference only
12.0MΩ-99.9GΩ：
±(10%+10)
100G-999GΩ：
±(20%+20)
1000GΩ- 10TΩ：
for reference only
OLOLOLOLOLOL
＞5.0mA
500V 1000V 2500V 5000V 10000V 12000V
500GΩ 1.0TΩ 2.5TΩ 5.0TΩ 10TΩ 10TΩ
500V 1000V 2500V 5000V 10000V 12000V
±(10%
±10V)
of
reading
0 +20%～
400V～600V
±(10%
±10V)
of
reading
0 + 0%～2
500V～1200V
±(10%
±10V)
of
reading
0 + 0%～2
1000V～3000V
±(10%
±10V)
of
reading
0 + 0%～2
2500V～6000V
±(10%
±10V)
of
reading
-0 + 0%～2
5000V～12000V
±(10%
±10V)
of
reading
-0～+ 0%2
12000V
±(3%+5) ±(3%+5)
9. Specifications
9.1.1 Insulation Resistance Measurement
9.1 Electrical Specifications
Error limit: ± (a% of reading + b digits), 1 year guarantee period
Ambient temperature: 23 °C±5 °C
Ambient humidity: 45~75%RH
Rated voltage
Max value
Accuracy
Over range
display
Short circuit
current
Output
current
1mA <output
current
<1.2mA at 0.5MΩ
1mA <output
current
<1.2mA at 1MΩ
1mA <output
current
<1.2mA at 2.5MΩ
1mA <output
current
<1.2mA at 5MΩ
0.15mA <output
current
<1.2mA at 10MΩ
0.15mA <output
current
<1.2mA at 12MΩ
9.1.2 Output Voltage
Rated
voltage
Display
accuracy
Output
accuracy
Settable
range
9.1.3 Voltage Measurement (Automatic Identification of AC/DC Voltage)
Measuring range
Accuracy
Over range display
DC voltage: 30V~1000V AC voltage: 30V~750V (50~60Hz)
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＞3.7mA
OL OL

33 34
0.00～999 0.00～999
±(10%+5)
9.1.4 Current Measurement
Measuring range
Accuracy
Effective test range of insulation resistance: 0.00nA~5.00mA
9.1.5 DAR and PI Measurement
Measurement mode
Display range
Computational error
DAR PI
± 2 digits ± 2 digits
9.2 Environmental Specifications
Operating Altitude: 2000m
Operating temperature and humidity: -10°C~50°C, ≤85%RH (no condensation when operating with the
power adapter); 0°C~40°C, ≤85%RH (no condensation when operating with batteries)
Storage temperature and humidity: -20°C~60°C, ≤75%RH (no condensation)
IP rating: IP67 (with the hard case closed)
9.3 General Specifications
LCD display: 320x240 pixels, 5.1 inch
Response time: About 30s within ±5% accuracy range; about 60s or longer for accuracy range ≥ ±10%
(the lower the output voltage, the longer the response time)
Overload protection: AC 1200V/10s
Withstand voltage: AC 8770V between lead terminal and housing/5s (50Hz/60Hz); AC 6880V between
measuring terminal and housing/5s (50Hz/60Hz); AC 2330V between power socket and housing/5s
(50Hz/60Hz)
Insulation resistance: 1000MΩ or more/DC 1000V (between electrical circuit and housing)
Dimensions: 410mm (L) × 350mm (W) × 200mm (D) (Tester and hard case)
Weight: about 9kg (including batteries) (Tester and hard case)
Power adapter: AC power adapter (220V/50Hz, 1A)
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10. Communication Function (Including Software)
The tester can be connected with a PC via the dedicated USB cable, as shown in Picture 23.
Download the corresponding PC software from the official website of Uni-Trend (refer to UNI-T Documents
Download Operation Guide), and install it according to the installation instructions.
Support Windows Vista, Win 7 or above system.
Use the USB cable to connect the tester with the PC. Short press the USB button on the tester and the
“USB” symbol will appear in the upper left corner of the LCD. The data of the tester is available for USB
communication now.
Run the PC software and click on the "Connect" option. Then the PC is available for USB communication
and the data of the tester will be displayed on the PC in real time.
Upload the data of the tester to the PC for saving, printing, analysis and other operation.
Data of the PC cannot be transmitted to the tester.
Picture 23
11. Use of Power Adapter
The power adapter operates at 220V/50Hz and has an output current of 1A. The tester can function properly
with the power adapter but cannot be charged. When the power adapter is enabled, power supply will be
automatically switched to the power adapter with battery power disconnected. Connection method of the power
adapter is shown in Picture 24.
Picture 24
Note: The power adapter is specially designed for UT516B. It cannot be replaced by other power adapters
as this may damage the tester or cause inaccurate measurement.
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12. Test Probe Metal Parts and Replacement
Standard metal tips for the metal part: Hook and straight types
Hook type: Used in the hanging test and installed on the test probe when purchased
Straight type: Need to be replaced for use
The method of replacing the metal tip is shown in Picture 25.
a) Rotate the top of the test probe to the left (counterclockwise).
b) Remove the mounted metal tip.
c) Insert the metal tip needed into the hexagonal jack and rotate it with the top of the probe to the right
(clockwise) together to tighten the screws.
Standard hook metal tip External thread
Hexagonal jack
Straight metal tip (accessory)
Picture 25
13. Maintenance
13.1 General maintenance
Wipe the tester housing with a soft cloth or sponge wetted with clear water.
Do not immerse the tester in water to avoid damage.
If the tester is wet, please store it after drying.
If the tester is not in use for a long time, please remove the batteries to avoid battery leakage and damage
to the tester.
The maintenance and service must be implemented by qualified professionals or designated departments.
13.2 Battery Replacement
The method of battery replacement is shown in Picture 26.
Disconnect the power adapter from the 220V circuit,
and remove the test leads from the terminals.
Power off the tester and let the power light go out.
Unscrew and remove the battery cover
(take care not to lose screws).
Replace with 10×1.5V alkaline batteries
(LR14) according to the polarity indication.
Secure the battery cover and tighten the screws.
Picture 26
UT516B User Manual UT516B User Manual
NOTE: DO NOT open the battery cover during any testing.