Time: 2022-05-30 Author: 铧正 Click: 304 Time
1. Before the measurement, the power supply of the device under test must be cut off, and ground short-circuit discharge is required. Never allow equipment to take real-time measurements to ensure the safety of people and equipment. For equipment that may induce high voltages, this possibility must be eliminated before making measurements.
2. The surface of the measured object should be clean. Reduce contact resistance to ensure correct measurement results.
3. Before the measurement, the megger should be analyzed and an open-circuit and short-circuit model test should be developed to check whether the megger is in good condition. That is, before the megohmmeter is not connected to the measured object, shake the handle so that the generator can reach a rated working speed (120r/min), and observe whether the data pointer information refers to the "∞" position of the time scale. Short-circuit the terminal "line (L) and ground (E)", slowly shake the handle, and observe that the pointer and whether it mainly refers to the "0" position of the scale. If the pointer problem cannot point to the position of the finger, it indicates that the megohmmeter is faulty. It should be repaired and used again.
4. The use should be placed in a stable and firm position, and away from large external current conductors and external magnetic fields.
5. The wiring must be correct. There are usually three terminals on a megohmmeter, where L is connected to the part of the conductor insulated from the object under test and ground, and E is connected to the case or ground of the object under test. G connects to the object under test or a shield that does not require the part under test. When measuring insulation resistance, usually only "L" and "E" terminals are used, but when measuring the insulation resistance of the cable to ground or the leakage current of the device under test is serious, the "G" terminal should be used, and the "G" terminal should be terminated on the shield or enclosure. After connecting the line, turn the crank handle clockwise, the crank speed should be slow and fast, when the speed reaches about 120 rpm (ZC-25 type), the crank handle should keep rotating at a constant speed. Read in a minute. Read while shaking. Don't stop reading.
6. Set it in the horizontal position during the test. When rotating the handle, no short circuit is allowed between the knobs at both ends. Shaking the handle should be gradually accelerated. If it is found that the pointer zero indicates that the insulation under test may be short-circuited, the handle cannot be shaken continuously. to prevent thermal damage to the countertop coil.
7. After reading, discharge the device under test. The discharge method is to remove the ground wire for measurement from the megohmmeter and short-circuit it with the device under test.
1. The instrument can be powered by two different ways of AC and DC, but when the power supply interference at the construction site is large or unstable, the battery is used for power supply.
2. When using the rechargeable battery, it needs to be charged for more than 6 hours. Otherwise, the instrument technology cannot meet the normal management work.
3. The charging circuit adopts an intelligent charging management module, which can automatically stop charging.
Note: The AC input voltage range of the charging adapter is 220v ± 15% to avoid unnecessary losses due to incorrect power supply.
4. Insert the DC end of the charging adapter into the power jack ⑨ of the instrument, and turn on the AC power at the other end. The charging indicator (red) lights up and fast charging starts.
5. When the battery technology is close to a full charge, the charging indicator (green light) lights up and switches to a slow charging state. After one end of time (1-2) hours, you can remove the plug and stop charging. Start to study the use of smart meters.
NOTE: When the instrument is not in use, make sure the band switch is off to avoid premature battery use.
HZJY-5K-I 5KV Insulation Resistance Tester