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MAINTENANCE
F
2. With the controller unplugged from the AC
power source, connect one test lead to
chassis ground and the other to the power
cord ground pin. Measure the resistance
value. The meter should measure less than
0.1 ohm.
3. If the reading obtained is greater than 0.1
ohm, the line cord or chassis wiring may be
damaged. The unit should not be placed
into use until the source of the problem is
determined and corrected.
4.7 Leakage Test
The purpose of this test is to measure the
amount of 50/60 cycle leakage from the
transformer primary to the circuitry of the
instrument. The AC leakage from any exposed
metal part to earth ground and from all exposed
metal parts having a return to chassis must not
exceed 100ma.
Test Equipment Required:
ED&D Leakage Current Tester, Model LT-601
or equivalent.
Procedure:
1. Plug the power cord into the back of the
controller. Plug the controller power cord
into the test instrument test receptacle.
2. Turn the controller on and allow to warm up
a minimum of two (2) minutes.
3. Measure the leakage current.
4. Turn the controller and test equipment off.
Disconnect all test equipment from the
controller.
5. If leakage exceeds limits, the unit may have
a faulty line cord or power transformer and
should not be placed into use until the
problem has been resolved.
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