BENSHAW RSi SG Series, Instruction Manual

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Chapter 7 – Trouble Shooting & Maintenance
7-7
7.4 How to Check Power Components
 Turn the power off and wait until the Main DC Bus Electrolytic Capacitors are discharged to a safe level.
The voltage between terminal P1-N (or P2-N) should be less than 30VDC.
 Disconnect input (R,S,T) and output (U,V,W) wiring. Proper test results may not be achieved if any of the
input or output wiring remains connected.
 A large reading of resistance such as Mega ohms (or OL) will be displayed when the circuit is Open. When
the circuit is closed, the resistance values will range from a few ohms to tens of ohms. Sometimes, a circuit
will seem to be closed (or give negative resistance readings) due to the meter charging up the electrolytic
capacitors within the circuit but high resistance will be eventually be displayed when the capacitors are
charged. A zero ohm reading (or short) indicates a bad (shorted) component.
 The measured values may not always be the exact same values depending on modules and tester types
however they should be similar.
WARNING