Precautions when testing the digital ground resistance tester

Digital Ground Resistance Tester Measurement Matters and Maintenance.

1. When measuring the protective grounding resistance, be sure to disconnect the connection point between the electrical equipment and the power supply. When measuring the grounding resistance less than 1, it should be connected to the grounding body with a special wire, C2 on the outside, and P2 on the inside (as shown in Figure 4).

2. When measuring the grounding resistance, it is best to repeatedly measure 3-4 times in different directions, and take the average value.

3. When measuring the grounding resistance of a large grounding power grid, it cannot be measured according to the general wiring method, and the buried plug can be selected with reference to the provisions of the ammeter and voltmeter measurement method.

4. If the test circuit is not open or exceeds the range, and the meter header shows "1" when it overflows, check whether the test circuit is connected well or whether it is out of range.

5. When the battery voltage is lower than the meter head, the meter head shows the undervoltage symbol "Grounding Resistance Tester" to indicate that the battery voltage is insufficient, at this time, the power cord should be plugged into the AC power supply or open the back cover of the instrument to replace the dry battery.

6. If you use a rechargeable battery, you can directly plug in the power cord and use the machine to charge, and the charging time is generally not less than 8 hours.

7. When storing and keeping this table, you should pay attention to the ambient temperature and humidity, and it should be placed in a dry and ventilated place to avoid moisture, and should prevent acid, alkali and corrosive gases, and should not be exposed to rain, exposure or fall.

1. Grounding resistance tester (also known as grounding resistance tester) is a device used to measure and test electrical grounding systems. Grounding ensures optimal electrical continuity between the conductive object and the ground, and effectively grounded equipment is permanently grounded by a grounding connection with sufficient low impedance and sufficient current-carrying capacity, and the grounding fault current does not cause dangerous voltage accumulation.

2. The grounding resistance tester can make several different measurements, including grounding system resistance, insulation resistance, grounding continuity, current leakage, and grounding resistance. Grounding system resistance and insulation resistance are common measurements made using a grounding resistance tester. Grounding System Resistance Tester is used to measure grounding systems in construction projects and roads, telecommunications projects, and other applications, and the Grounding Resistance Tester measures the resistance of an insulator or insulator.

3. The grounding resistance measuring instrument can be used to measure grounding continuity, current leakage and grounding resistance, grounding continuity equipment is used to test electronic instruments and equipment, and the current leakage tester measures the amount of current leaked to the ground, these devices are essential to maintain the safety of instruments in contact with people. Ground wire ground resistance testers are used for ground wire or high current continuity testing, perform these tests to confirm the electrical integrity of the instrument, other types of earth resistance testers can also be used.

4. Most ground resistance testers have an analog or digital display or LED indicator, the analog meter displays the value on the dial, usually by the pointer when the signal is applied, the digital meter provides digital readings, light-emitting diodes (LEDs) and liquid crystal displays (LCD) are common types of digital displays, the LED indicator uses the indicator to indicate that the test is in progress, and in some models, the LED light flashes throughout the test.

5. The ground resistance tester comes with several different interfaces, the options include a rolling ball printer port, a scanner port and a printout, a universal interface bus (GPIB) for connecting computers, peripherals and lab equipment, an interface for a ground resistance tester for serial communication between the instrument and a computer, a printer port device with a connected connector or port designed to interface with the printer, a scanner port similar to the printer port but designed to interface with the scanner. Another common interface for a ground resistance tester is a printout, which is a hardcover copy of formatted data collected during the test, and other types of earth resistance tester interfaces can also be used.

The grounding resistance can be a good measure of the grounding state of the wire, so it is safer to measure the wire when it is connected, and the data must be within the standard range. Generally speaking, when testing the grounding resistance, the test instrument that the cursor wants will be used, that is, the grounding resistance tester, so what is the use of the grounding resistance tester? Let's take a look with Qeeka Home experts.

1. What is the use of the grounding resistance tester?

Prepare a complete tester first, check the buried accessories, and require two grounding rods, one for auxiliary grounding and the other for detecting electrodes; Then insert the two grounding rods into the ground respectively, keep the depth at 400mm, and keep a distance of 20m between the two. Finally, place the shaker in a flat place next to the grounding body, and you can start the test.

2. What problems should be paid attention to when using a grounding resistance tester?

1. Pay attention to the selection of current.

Generally, the current in the grounding body is mainly based on AC fault current and lightning current, that is to say, the abnormal use of the circuit will pass through the grounding body, so when testing, it is necessary to select the appropriate current to test, so as to test the real resistance value data. If the lightning current is tested, it is a high-frequency current, so the DC ammeter cannot be selected for testing.

2. Pay attention to the arrangement of the pole.

When the tester is used, it is necessary to pay attention to the arrangement of the ground pole, if it is to test the A ground pole potential, the K ground electrode of the ground rod must be inserted in the CD, that is, the zero potential area, once the plug is wrong, the test result is inaccurate, and the actual situation can not be reflected, and it is very likely that the resistance value is small or large.

Summary: The above is an introduction to the use of the grounding resistance tester and what problems should be paid attention to when using the grounding resistance tester. I hope that the content shared can give you some reference, and if you want to know more about related knowledge, you can **** Qeeka Home Information.

1. Two-line method.

Conditions: There must be a ground that is known to be well grounded, such as pen, etc., and the measured result is the sum of the resistance of the ground being measured and the known ground. If the ground is known to be much smaller than the resistance of the ground to be surveyed, the measurement results can be taken as the result of the ground being surveyed.

It is suitable for: dense buildings or cement floors and other areas where sealing cannot be driven piles.

Wiring: E+ES to the ground being surveyed, H+S to the known ground.

2. Three-line method.

Conditions: There must be two ground rods: an auxiliary ground and a probe electrode. The distance between the grounding electrodes is not less than 20 meters.

The principle is to add a current between the auxiliary ground and the ground to be measured to measure the voltage drop between the ground to be measured and the probe electrode, and the measurement results include measuring the resistance of the cable itself.

Suitable for: foundation grounding, construction site grounding and lightning protection ball type lightning rod QPZ grounding.

Wiring: S is connected to the detection electrode, H is connected to the auxiliary ground, E and Es are connected to the ground to be measured.

3. Four-line method.

Basically the same as the three-wire method, which replaces the three-wire method when measuring low ground resistance and eliminating the influence of the resistance of the measurement cable on the measurement result, E and ES must be separately connected directly to the ground being measured. This method is the most accurate of all ground resistance measurement methods.

4. Single-clamp measurement.

Conditions: Measure the ground resistance at each ground point in the multi-point ground, and the ground connection cannot be disconnected to prevent a dangerous balance.

Suitable for: multi-point grounding, can not be disconnected, measure the resistance of each grounding point.

Wiring: Monitor the current at the measured grounding point with a current clamp.

5. Double pincer method.

Conditions: multi-point grounding, no auxiliary ground piles, ground state measurement single grounding.

Wiring: Use the current specified by the manufacturer to clamp to the corresponding socket, and clamp the two clamps on the grounding conductor, and the distance between the two clamps should be greater than meters.

The grounding resistance tester is a new type of digital grounding resistance tester that abandons the traditional manual hand-cranked power generation working method, adopts advanced large-scale integrated circuits, and applies DC AC conversion technology to combine the measurement methods of three-terminal buttons and four-terminal buttons into one model. Next, I will tell you about the measurement steps of the ground resistance tester, come and take a look!

1.Two grounding probes are inserted into the ground 20m, 40m respectively from the grounding body along the radiation direction of the grounding body, and the insertion depth is 400mm, as shown in the figure below. Ground resistance test used**.

Ground resistance test using **:aPractical operation bPrinciple of equivalence.

2.Place the grounding resistance measuring instrument flat near the grounding body, and wire, the wiring method is as follows:

Use the shortest dedicated wire to connect the grounding body with the terminal "E1" of the grounding measuring instrument (a measuring instrument with a three-end button. Or with C2, "short after the common end of the gauge (four-end button. Connected.

Use the longest dedicated wire to connect a measuring probe (current probe) that is 40 m away from the grounding body. It is connected to the terminal knob "C1" of the measuring instrument.

Use a dedicated wire centered on the remaining length to distance the measuring probe (potentiometric probe) from the grounding body m. It is connected to the terminal "P1" of the measuring instrument.

3.After placing the meter horizontally, check that the pointer of the galvanometer is pointing towards the center line, otherwise adjust the "zero adjuster" so that the meter pointer points to the center line.

4.Drag the Magnification Scale (or coarse knob. Place at the maximum multiplier and slowly turn the generator handle (the pointer begins to shift.) and rotate the Measuring Dial (or fine adjustment knob) at the same time. Point the galvanometer pointer toward the centerline.

5.When the needle of the galvanometer is close to equilibrium (the pointer is close to the center line. Speed up the shaking of the handle so that its rotational speed reaches more than 120r min, and adjust the "measuring dial" so that the pointer points to the centerline.

6.If the reading of the "Measuring Dial" is too small (less than 1.).If it is not easy to read accurately, it means that the magnification scale multiple is too large. At this point, you should place the Magnification Scale in a smaller multiple, readjust the Measurement Dial so that the pointer points to the centerline and read an accurate reading.

7.Calculate the measurement result, i.e. r = "magnification scale" reading "measurement dial" reading. ;