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I.Use safety measures
1. Be sure to read this manual carefully before using this instrument.
2. Test personnel should have common sense of using general electrical equipment or
instruments.
3. The tester must strictly abide by the safety operation regulations, and must fully
understand the high-voltage test circuit and the main points of the instrument operation.
4. Non-testing personnel must stay away from the high-voltage test area. The test area
must be clearly indicated by fences or ropes, police signs, etc.
5. This instrument can only be used on power-off equipment; it must be ensured that the
ground terminals of the instrument and the equipment under test are reliably connected to
the ground network.
6. When the fuse is damaged, you must make sure to replace the fuse of the same
specification.
7. When the instrument fails, turn off the power switch and wait for one minute before
checking.
8. The instrument should avoid severe vibration.
10. The maintenance, care and adjustment of the instrument should be carried out by
professionals.
II.Instrument overview
At present, in the power system, the grounding resistance test of the earth network
mainly adopts the power frequency high current three-pole method. In order to prevent
the power frequency interference generated during the operation of the power grid and
improve the accuracy of the measurement results, the insulation preventive test
regulations stipulate that the test current of the power frequency high current method
shall not be less than 30A. As a result, many problems such as heavy test equipment,
complicated test process, high work intensity of test personnel, and long test time
appeared.
Summary of Contents for HZDW-DB
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