1. Introduction
The insulation resistance tester—also known as a megohmmeter, high-voltage insulation resistance tester, etc.—is used for measuring insulation resistance.
2. Voltage Ranges and Accuracy
| Measurement Function |
Measurement Range |
Accuracy |
Resolution |
| DC Voltage |
DC 0.0V – 1000V |
±1.5% rdg ±3 dgt |
0.1V |
| AC Voltage |
AC 0.0V – 750V |
±1.5% rdg ±3 dgt |
0.1V |
3. Technical Specifications
| Functions |
Insulation Resistance Test, Voltage Test, DC Current Test, Capacitance Test |
| Reference Conditions |
23°C ±5°C, <75% RH |
| Rated Voltage |
100V, 250V, 500V, 1000V, 2500V, 5000V |
| Insulation Resistance Range |
0.01 MΩ – 10 TΩ | Resolution: 0.01 MΩ |
| Rated Voltage |
250V, 500V, 1000V, 2500V, 5000V, 10 kV |
| Insulation Resistance Range |
0.01 MΩ – 35 TΩ | Resolution: 0.01 MΩ |
| Rated Voltage |
500V, 1000V, 2500V, 5000V, 10 kV, 15 kV |
| Insulation Resistance Range |
0.01 MΩ – 50 TΩ | Resolution: 0.01 MΩ |
| Measurement Voltage (V) |
Rated Voltage × (1 ±10%) |
| DC Voltage Range |
0 – 1000V | Resolution: 0.1V |
| AC Voltage Range |
0 – 750V | Resolution: 0.1V |
| DC Current |
0.1 nA – 6 mA | Resolution: 0.1 nA |
| Capacitance |
10 nF – 50 µF | Resolution: 10 nF |
| Output Short-Circuit Current |
≥6 mA @ 15 kV |
| Absorption Ratio (DAR) and Polarization Index (PI) Measurement |
Supported |
| Power Supply |
12.6V Rechargeable Lithium Battery |
| Backlight |
Supported Controllable gray-white screen backlight, suitable for use in dimly lit environments. |
| Display Mode |
4-digit extra-large LCD display with gray-white screen backlight. |
4. Measurement Principle
Insulation resistance measurement employs a voltage generator to generate a voltage V, which is applied across the resistor. By measuring the current I flowing through the resistor, the ground resistance value R is calculated using the formula R = V/I.
Safety Precautions:
In all circumstances, special attention must be paid to safety when using this instrument.
This instrument has been designed, manufactured, and tested in accordance with the IEC 61010 safety specifications.
In all circumstances, special attention must be paid to safety when using this instrument.
During measurements, do not use high-frequency signal generators—such as mobile phones—in the vicinity of the instrument, as this may introduce measurement errors.
Pay close attention to the text and symbols displayed on the labels affixed to the instrument's casing.
Before use, verify that the instrument and its accessories are in good condition; specifically, ensure that the insulation on the instrument and test leads is intact, with no exposed conductors or broken wires, before proceeding with measurements.
During the measurement process, strictly avoid touching exposed conductors or the circuit currently being tested.
Ensure that the connection plugs of the test leads are firmly inserted into the corresponding ports on the instrument.
Do not perform measurements in flammable environments, as sparks generated during operation could trigger an explosion.
If the instrument's casing or test leads become damaged—exposing internal metal components—while the unit is in use, immediately cease operation.
Do not leave or store the instrument for extended periods in environments characterized by high temperatures, high humidity, condensation, or direct sunlight.
When replacing the instrument's batteries, ensure that the test leads have been disconnected from the unit and that the instrument is powered off.
If the instrument displays the "Low Battery Voltage" symbol, recharge the unit immediately; failure to do so may result in measurement inaccuracies.
Strictly avoid performing charging or data transmission operations while a measurement is in progress.
