in the EPWT-10B ?

General Information:
DC resistance test is a must-test item for semi-finished products, finished products factory test, installation, handover test and preventive test of power sector in the manufacture of inductive coils such as transformers, mutual inductors, reactors, electromagnetic operating mechanisms, etc. It can effectively discover the selection and welding of inductive coils, Loose connection parts, missing strands, broken wires and other manufacturing defects and hidden dangers after operation. It is also an essential test item for transformers after handover, overhaul and change of tap changer. At the same time, similar to dry-type transformers and amorphous alloy transformers, since the low-voltage coils are wound with copper foil, the resistance value is extremely low, which brings high precision and resolution requirements to the test. Under normal circumstances, testing the DC resistance of transformer windings and high-power inductive devices by traditional methods (bridge method and voltage drop method) is a time-consuming and labor-intensive task. In order to meet the needs of fast testing of inductive coil DC resistance, improve the test accuracy of DC resistance, shorten the test time and reduce the testing burden of testers, this DC resistance tester has been developed. The maximum output current range of EPWT-10B is designed to be 10A, which solves the problem of low-value resistance testing. At the same time, for high-resistance samples such as transformers, the meter also extends the DC resistance test range to 1MΩ, which is an ideal device for testing the DC resistance of transformer windings and high-power inductive equipment.

The EPWT-10B Transformer Winding Resistance Tester also adopts 5.6-inch color LCD display, simple and beautiful operation interface, built-in rechargeable lithium battery and charging circuit, with high-speed microcontroller as the core, combined with high-speed A/D converter and program-controlled current source technology, with resistance temperature conversion function , In circuit design, it has a variety of protection functions such as back EMF protection, disconnection protection, power failure protection, and overheating alarm. In order to achieve high-precision, high-stability, high-speed testing, it also has the characteristics of self-test, automatic discharge, large output current, wide range, strong anti-interference ability, fast charging and discharging speed, data analysis and processing, and discharge indication.

Main technical data table:


Transformer winding resistance test, low resistance test, equipotential bonding resistance test, metal connection resistance test, micro-ohmmeter

Power Supply

Built-in: 14.8V 7800mAh rechargeable lithium battery;

External: AC 220V/2A 50Hz/60Hz

Test Method

four-wire method


16.8V/2A charger

Display Mode

5.6-inch LCD color screen, 640dots×480dots, display area 116mm×88mm

Test Interface

I+ (current positive), I- (current negative), U+ (voltage positive), U- (voltage negative)

Output Current

10A, 5A, 1A, 400mA, 200mA, 40mA, <5mA


(Mains 220v)

500μΩ~1.5Ω 10A

1mΩ~4.4Ω Constant current 5A

10mΩ~22Ω Constant current 1A

25mΩ~55Ω Constant current 400mA

200mΩ~110Ω Constant current 200mA

1Ω~550Ω Constant current 40mA

10Ω~1MΩ Constant voltage <5mA


(Built-in battery)

500μΩ~200mΩ Constant current 10A

1mΩ~800mΩ Constant current 5A

10mΩ~12Ω Constant current 1A

25mΩ~30Ω Constant current 400mA

200mΩ~60Ω Constant current 200mA

1Ω~300Ω Constant current 40mA

1Ω~1MΩ Constant voltage 12V <5mA

Max. resolution


Test accuracy

Constant current file: 0.1%;

Constant pressure gear: 2%

(23℃±5, below 80%RH)

Overrange prompt


Discharge Tips

After the test, the buzzer sounds to indicate that the discharge is in progress, and the buzzer stops after the discharge is completed.


The instrument panel is embedded with a printer, press the print button to print the test results

Data Storage

After the test is completed, the data is automatically saved, and the cycle is saved, which can store 9999 sets of data

Meter Size

About 320mm(L)×275mm(W)×145mm(H)

Package Size

About 400mm(L)×245mm(W)×335mm(H)


Instrument: about 9.2kg (including packaging)


Tool box can bear 200kg

Test Line

Both ends of the test lead are tapped, and the wiring is simple


Constant current:10 A, 5 A, 1A, 400 mA, 200 mA, 40mA

Constant voltage: <5mA

Also has Auto automatic shifting

Output Power

150 watts max

Data Deletion

In the data review column, you can choose to delete the current data or delete all data

Data Access

Press the up and down keys to browse the stored data in the data review bar

Firmware Upgrade

The user can upgrade the instrument program through the U disk

Automatic Shut-Down

When using battery power, it will automatically shut down after about ten minutes of no operation.

Battery Voltage

There is a battery indicator on the upper right corner of the meter. When the symbol “ ” is displayed, it means that the battery is exhausted, and the meter will automatically shut down. Please charge it in time.

Temperature Conversion

The instrument automatically processes the test data and has the function of resistance temperature conversion

Data Transmission

It can be transmitted through RS232, U disk, Bluetooth, etc.


Backlight can be set to high, medium and low brightness

Test Type

Optional Cu, Al material

Converted Temperature

The tested resistance value can be converted to the resistance value at two temperatures of 75°C and 15°C


00-99 can be set

Working Current

The working current is 200mA in the non-test state

Circuit Protection

With back EMF protection, disconnection protection, power failure protection, overheating protection, etc.

Working Temperature And Humidity

-20℃~40; below 80%RH, no condensation

Storage Temperature And Humidity

-10℃~60; below 70%RH

Suitable For Safety Regulations

IEC61010-1, CAT Ⅲ 600V, pollution level 2, JJG724-1991 "Verification Regulations for DC Digital Ohmmeter", JJG166-1993 "Verification Regulations for DC Resistors", "DL/T967-2005 Loop Resistance Tester and DC Resistance Fast Tester Verification Regulations"

More details on Transformer DC Winding Resistance Tester, Transformer Ohmmeter Please contact Wuhan EP Hipot Electric.