1. Working Principle

This table abandons the traditional manual power generation mode, adopts advanced medium and large scale integrated circuits, and combines three-terminal and four-terminal button measuring methods with DC/AC conversion technology into a new type of ground resistance measuring instrument.

The working principle is that the DC/AC converter converts DC into AC low frequency constant current. The circuit is composed of auxiliary grounding pole C and measured object E. The measured object generates AC voltage drop, which is amplified by auxiliary grounding pole P into AC amplifier, and then sent to the meter head for display after detection. With the help of multiplier switch, three different limits can be obtained: 0-2_, 0-20_and 0-200_.

2. Scope of Use

This table is suitable for measuring grounding resistance of various devices and conductor resistance value of low resistance in electric power, post and telecommunication, railway, communication, mining and other departments. It can also measure soil resistivity and ground voltage.

1. Conditions of Use

Ambient temperature: 0 ~45.

Relative humidity: <85%RH

2. Measurement Range and Constant Current Value (RMS)

Resistance: 0-2_(10mA), 2-20_(10mA), 20-200_(1mA)

Voltage: AC 0-19.99V

3. Measurement accuracy and resolution

Accuracy: 0-0.2 < 3%+1d

0.2~199.9 < 1.5%+1d

1-19.99V <3%+1d

Resolution: 0.001_, 0.01_, 0.1_, 0.01V

4. Measurement Errors Caused by Auxiliary Grounding Resistance and Ground Voltage

Allow auxiliary grounding resistance RC (between C1 and C2)

0-2_, 2-20_ < 1K_

20-200_ < 2K_

The error of RP (between P1 and P2) <40K is <5%.

Permissible Ground Voltage (RMS of Power Frequency) <5V Error <5%

5. Power Supply and Power Consumption

Maximum Power Loss <2W

DC: 8 x 1.5V (AA, R6) battery

Communication: 220V/50Hz

6. Volume and weight

Volume: 220 mm x 200 mm x 105 mm >

Structurally, high strength aluminium alloy is used as the housing. In order to prevent power frequency and radio frequency interference, phase-locked loop synchronous tracking detection mode and switched capacitor filter are used in the circuit to make the instrument have better anti-interference ability.

DC/AC conversion technology is used to convert DC to AC low frequency constant current for easy measurement.

The auxiliary grounding resistance is allowed to change between 0~2K_(RC) and 0~40K_(RP) without affecting the measurement results.

This instrument does not need to adjust the balance manually. 3 (1/2) bit LCD shows that besides geodesic resistance, it can also measure low resistance conductor resistance, soil resistivity and AC ground voltage.