MD9910 Grounding Conductivity Tester

MD9910 Grounding Conductivity Tester

I. Overview

The reliable and effective connection between the grounding down conductor of power equipment and the grounding grid is the fundamental guarantee for the safe operation of the equipment. The grounding down conductor is the connection part between power equipment and the grounding grid. During the long-term operation of power equipment, the connection may be affected by moisture and other factors, resulting in rusting or even breakage of the contact points, which can increase the resistance of the grounding down conductor and the main grounding grid connection point and fail to meet the requirements of power regulations. This poses a safety hazard to the equipment during operation, and in severe cases, can cause the equipment to lose ground and operate. Therefore, in the "25 Key Requirements for Preventing Major Accidents in Power Production", it is explicitly stated that the continuity testing of grounding device down conductors should be conducted once a year.

The grounding continuity resistance tester is a highly automated portable tester developed by our company, used for measuring the continuity resistance values between the grounding down conductors of various power equipment in substations. The instrument is controlled by a high-performance microcontroller, which can achieve intelligent testing process. It has the advantages of small size, easy portability, simple operation, high accuracy, fast testing speed, good repeatability, and intuitive reading. It is an ideal instrument that meets the requirements of regulations.

2、 Security measures

1. Before using this instrument, be sure to read this manual carefully.

2. This instrument can be used both indoors and outdoors, but should be avoided from places such as rain, corrosive gases, etc.

3. Instruments should avoid severe vibrations.

4. The maintenance, care, and adjustment of instruments should be carried out by professionals.

5. After the test is completed, be sure to reset the instrument and turn off the power before removing the test line.

6. During the testing process, it is prohibited to move the test clip or cut off the power supply line.

3、 Functional Features

1. The whole machine is controlled by a high-speed microcontroller, with a high degree of automation and easy operation.

2. The instrument adopts a new power technology and has a wide measurement range.

3. Protection function *, more reliable performance.

4. Fast response speed, stable instrument measurement data, and automatic data refreshing during instrument testing.

6. Intelligent power management technology ensures that instruments always operate at low power levels, effectively reducing internal heat generation and saving energy.

7. The instrument is equipped with a non power-off clock inside.

8. The instrument has an internal non power down memory that can store data.

4、 Technical indicators

1. Output current: automatic, 10A, 5A, 1A, 200mA, 40mA,<5mA

2. Resolution: 0.1 μ Ω

3. Range: 100 Ω -100K Ω (<5mA range)

1Ω-500Ω （40mA 档）

100mΩ-100Ω (200mA 档)

5mΩ-20Ω (1A 档)

1mΩ-4Ω (5A 档)

0.5mΩ-2Ω (10A 档)

4. Accuracy: 0.2%

5. Working temperature: 0-40 ℃

6. Working humidity:<90% RH, no condensation

5、 System Introduction

The panel of the instrument is shown in the following figure

Power supply~220V: The entire machine has a power input port with an AC socket, fuse, and switch.

Reset button: Pressing this button will put the device in its initial state and preset the output current.

Loop key: Press this key to scroll the cursor in a loop through the main menu

Selection: After resetting the device, press this button to preset the current.

Start: After selecting the output current, press this button to control the entire testing process through the microcomputer. Brightness: The brightness of the display screen can be adjusted by turning the knob below the screen.

Grounding point.

I+, I -: Output current terminal, where I+represents positive output current and I - represents negative output current.

V+, V -: V+is the positive terminal of the voltage line, and V - is the negative terminal of the voltage line.

6、 Testing and operation methods

The instrument wiring is shown in the following figure: connect the red test wire plug to I+, the plug rod to V+, clamp the test clamp to one end of the test sample, connect the black test wire plug to I -, the plug rod to V -, and the test clamp to the other end of the test sample.

1. The startup page is displayed as shown in the following figure:

Press the cycle key to move the cursor between modifying the clock, querying data, and selecting current. Press the select key to select the test current. After selecting the test current, press the start key to start the measurement. In the interface shown in the figure, regardless of the position of the cursor, pressing the start button can start the measurement.

2. In the above figure, press the loop key to move the cursor to modify the clock, as shown below:

Press the selection key to enter the clock modification and query interface, as shown below:

In the above figure, pressing the cycle key can move the cursor between various date data, pressing the select key to decrease data, and pressing the start key to increase data.

3. Move the cursor to the data query menu on the startup page, and then press the selection key to enter the data query

4. After selecting the current, press the confirm button to start the test. After a few seconds, the LCD displays "charging" and then "testing", indicating that the charging is complete and entering the testing state. After a few seconds, the measured resistance value will be displayed, as shown in the following figure. When choosing automatic testing, the instrument will automatically select the appropriate current for testing based on the condition of the test sample. After stabilizing the data, press the selection key to print the current data.

5. After the test is completed, press the "Reset" button to disconnect the instrument output power, restore the LCD to its initial state, reconnect for the next measurement, or disconnect the test line and power line after turning off the power to end the measurement.

7、 Precautions

1. When connecting the test clip to the grounding wire contact end, it is important to note that the contact end is exposed to air for a long time and covered with an oxide film on the surface. This oxide film may cause unstable or inaccurate measurement results. Therefore, when wiring, it is important to clean the oxide film, or after connecting the test clip to the lead out end, twist the test clip vigorously a few times to cut through the oxide film to ensure a good connection.

2. Before disconnecting, be sure to wait for the instrument to reset and turn off the power before disconnecting.

3. When selecting the current, refer to the range in the technical specifications column and do not use it beyond or below the range. When the current exceeds the preset value, the instrument remains in the "charging" state. When the range is insufficient, it displays' current too low '. When these two states occur, confirm the range and select the appropriate current for testing.

8、 Instrument completeness

One grounding continuity tester host

One set of 10A testing line

One three core power cord

Two insurance pipes

One user manual

Two rolls of printing paper

One grounding wire

A standard resistor

One certificate of conformity

Warranty sheet

Packing list sheet

9、 After sales service

Within one year from the date of purchase, any quality issues related to the company's products will be repaired free of charge, and lifetime warranty and technical services will be provided. If any abnormality or malfunction is found in the instrument, please contact the company in a timely manner so that we can arrange a convenient solution for you and provide you with fast on-site service.