GE ApexPro, Руководство по обслуживанию

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Revision C ApexPro Telemetry Server 4-13
2001989-178
Maintenance: Electrical Safety Tests
For EQUIPMENT without a POWER SUPPLY CORD the impedance between the
PROTECTIVE EARTH TERMINAL and any ACCESSIBLE METAL PART
which is PROTECTIVELY EARTHED shall not exceed 0.1 ohms
For EQUIPMENT with a POWER SUPPLY CORD the impedance between the
protective earth pin in the MAINS PLUG and any ACCESSIBLE METAL PART
which is PROTECTIVELY EARTHED shall not exceed 0.2 ohms.
When taking this measurement, move the customer’s power cord around, no
fluctuations in resistance should be observed.
Ground (Earth) Wire Leakage Current Tests
Perform this test to measure current leakage through the ground (earth) wire of the
equipment during normal operation.
1. Set the leakage tester switches as follows:
‹
Set the GND switch to GND OPEN.
‹
Set the polarity switch to NORM/FORWARD.
‹
Set the power switch to OFF.
2. Connect a digital multimeter (DMM) to the METER jacks on the leakage tester.
Set the DMM to measure AC millivolts.
3. Connect the power cord of the device under test to the power receptacle on the
rear of the leakage tester.
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The device under test is to be tested at its normal operating voltage.
4. Set the leakage tester power switch to ON.
5. Set the power switch of the device under test to ON.
6. Read the current leakage indicated on DMM. If the reading is greater than
3.5mA, the device under test fails and should be repaired and tested again.
7. Set the polarity switch on the leakage tester to RVS (reverse).
8. Read the current leakage indicated on DMM. If the reading is greater than
3.5mA, the device under test fails and should be repaired and tested again.