Point to point resistivity tester instructions and precautions

Ready to work

(1) Install the battery

Open the back cover of the case, and insert 8 sections of R20 No. 1 battery according to the direction indicated on the rear cover. Use common 1.5V alkaline batteries, zinc-manganese batteries, or 1.2V rechargeable batteries. It is recommended to use liquids that do not leak. Iron shell battery.

(2) Supply voltage check

Turn the high voltage (zero) selection switch to the “Battery” position. The “B(V)” character appears on the display. The displayed value is the voltage value of the battery. If the battery symbol (13) appears on the display, the battery voltage is over. Low, must be replaced in time.

Steps

Before starting the operation, the power supply of the instrument should be in the off position. After the previous measurement is completed, an internal discharge time of about 30 seconds should elapse to ensure that the operator is protected from high voltage electric shock.

1, according to Figure 3, the test sample is placed flat on the insulating table, the electrode measurement scale is placed on the test sample, the conductive rubber is placed in the two apertures of the electrode measurement rule, the electrode is placed on the conductive rubber, and then Remove the electrode measurement scale and connect the high-voltage output and measurement input of the instrument to the two electrodes respectively (the shield is not used).

Note: The human body must not touch the metal surface of the electrode during measurement! Everyday attention must be paid to ensure that the surface of the conductive rubber and electrode is clean and flat. If there is any dirt, do not use a sharp tool to wipe it.

2. Place the override (range) switch in the lowest gear. The minimum magnification of this instrument is ×105Ω, and the resistance measurement must start from the lowest range. This is because the measured object may have a large distributed capacitance. The resulting charging current may be highly sensitive to the input of the instrument at the instant of the start of measurement. Cause harm.

3. Set the high voltage (zeroing) selector switch to the “discharge zero” position above 100V.

4. Turn on the instrument's power switch.

5, according to the specific circumstances, open the filter 1 or filter 2 switch.

When the resistance above 1012Ω is measured in a place where the environmental interference is serious, the filter 1 and filter 2 switches can be used in combination to keep the reading of the instrument stable. The effect of filter 2 is slightly stronger than that of filter 1, and if both switches are open (upwards) at the same time, the filtering function is the strongest. In the general case, the filter 1 and filter 2 switches should be placed in the off (down) position, so that the instrument has a faster response speed.

6, zero school - to confirm that high-pressure (school zero) selector switch has been dialed to 100V above the "discharge calibration zero" gear, adjust the zero calibration knob (8) so that the instrument showed the value of .000.

7, open the timer switch.

The charging time required for the 8,100V test voltage is very short. Quickly turn the high voltage (zero) selection switch to 100V. The test voltage is applied to the measured object. The resistance measurement starts and the timing begins. After 15 seconds, the “H” character appears on the lower left of the display, and the indication is automatically locked.

Observe the instrument's indication. If the display shows “1—” (there is no reading after a single “1” character), the instrument's range is too small. Gradually rotate the override (range) switch clockwise, and stop the rotation immediately after the reading appears. Usually, the instrument indication should be between 100 and 1999 words (ignoring the decimal point). If the value is less than 100 words, you can rotate the magnification (range) switch one counterclockwise for accuracy and accuracy. Resolving power. If the symbol “×” appears on the display, the instrument is in an excessively large range. The override (range) switch should be turned counterclockwise quickly. If the “×” symbol still appears at the lowest override, the device under test is short-circuited. Immediately switch the switch to the "discharge calibration zero" position and disconnect the resistance measurement circuit. Note: Instrument readings are invalid when the “×” symbol appears. The input of the instrument is affected by over-current, and the zero position may be temporarily offset. Usually it can be restored after a period of time.

Insulation resistance of the measured object = instrument indication × magnification

9, record this value. The switch is set to the “discharge calibration zero” position. At this time, the measurement voltage is disconnected and the discharge circuit is connected. After about 15 seconds, after the device under test is fully discharged, the operator can contact the high voltage terminal and the measurement terminal.

10, interval of 3-5 minutes, to be fully discharged on the test specimen after the release of the electrode, repeat the above steps, the next set of data measurements.

11. After all tests are completed, turn off the power switch, close the timer switch, turn off the filter 1, and filter 2 switches; turn the high voltage (zeroing) selector switch to the “discharge calibration zero” position above 100V; override (range) switch setting In the lowest gear; organize and properly place test clips, power cords, electrodes, conductive rubber, and electrode measurement scales.

Precautions

1, built-in battery and external power supply, can only choose one of the power supply.

2. When the instrument is not in use, place it in a dry and ventilated place.

3, when not in use for a long time, please take out the battery from the battery box, in order to prevent the battery from leaking and corroding the instrument.

4, non-professional maintenance personnel shall not open the instrument cover to prevent the shock from the high voltage inside the machine. Freely open the cover to disassemble and modify the internal components of the instrument may lose the warranty qualification of the instrument or increase the cost of repair. Never use corrosive fluxes such as hydrochloric acid or solder paste to solder the measuring leads, connectors, or internal components of the instrument to avoid irreparable electrical leakage.