Precautions for Explosion-proof Mining Current Tester
Before measurement, insert the test leads into the internal test lead holes respectively, and insert both ends of the connecting wire into the two jacks respectively, and adjust the meter pointer to indicate zero line.
Place the test rods connected to the binding posts on the two points to be measured (such as rails, cable sheaths, coal, etc.), and set the switch to the appropriate gear. The meter reading is the stray current value between the two points. When the pointer turns right, it is positive; when it turns left, it is negative.
When measuring stray voltage, you can separate the connecting forks in the two color posts. At this time, the meter reading is the voltage value, with mA corresponding to mV and A corresponding to V.
When the stray current magnitude is unknown, first set to the maximum range gear, then gradually decrease to the appropriate measurement gear. The instrument should be placed horizontally.
When the measured current exceeds 5A, the instrument should only be used for short-time measurement. When the measured current exceeds 10A, only instantaneous measurement is allowed.
When the instrument is not in use, it should be set to the (off) position.
I. Usage Methods and Precautions
1. Before measurement, screw the test rod wires into the two binding posts respectively, and adjust the meter pointer to the zero scale line.
2. Place the test rods connected to the binding posts on the two points to be measured (such as rails, water pipes, cable sheaths, coal, ground, etc.). The two test points should be on different conductors, with a distance of about 2 meters. Normally, measure every 50-100M, or temporarily determine test points as needed. Set the switch to the appropriate gear, and the meter reading, after conversion, gives the corresponding current value.
3. During measurement, the hard alloy tip of the measuring probe should make good contact with the object being measured, and the instrument should be placed horizontally to ensure accurate readings.
4. When AC stray current cannot be measured at a location, DC stray current should also be tested, and vice versa.
5. When measuring stray voltage values, the gears are: 50mA corresponds to 0.2V, 250mA corresponds to 1V, 1A corresponds to 4V, 5A corresponds to 20V, 10A corresponds to 40V. (That is, the current value multiplied by 4 gives the voltage value)
6. When the stray current magnitude is unknown, first set to the maximum range gear, then gradually decrease to the appropriate measurement gear.
7. When the measured current exceeds 5A, the instrument should only be used for short-time measurement. When the measured current exceeds 10A, the instrument should only be used for instantaneous measurement to avoid large currents burning out components and the instrument.
8. When measuring DC stray current, if the meter pointer deflects in the reverse direction, swap the test leads.
9. When the instrument is not in use, it should be set to the "off" position.
II. Completeness of the Stray Current Tester Product
1. Main unit: one unit
2. Test leads: one pair
3. Product manual: one copy
4. Product certificate of conformity: one copy
