WARNING
HAZARD OF SHOCK AND ELECTROCUTION. A CAPACITOR CAN HOLD A CHARGE FOR LONG PERIODS OF TIME. A SERVICE TECHNICIAN WHO TOUCHES THESE TERMINALS CAN BE INJURED. NEVER DISCHARGE THE CAPACITOR BY SHORTING ACROSS THE TERMINALS WITH A SCREWDRIVER.
Capacitors
Many motor capacitors are internally fused. Shorting the terminals will blow the fuse, ruining the capacitor. A 20,000 ohm 2 watt resistor can be used to discharge capacitors safely. Remove wires from capacitor and place resistor across terminals. When checking a dual capacitor with a capacitor analyzer or ohmmeter, both sides must be tested.
Capacitor Check With Capacitor Analyzer
The capacitor analyzer will show whether the capacitor is "open" or "shorted." It will tell whether the capacitor is within its microfarads rating and it will show whether the capacitor is operating at the proper
the test switch is released
Capacitor Connections
The starting winding of a motor can be damaged by a shorted and grounded running capacitor. This damage usually can be avoided by proper connection of the running capacitor terminals.
From the supply line on a typical 230 volt circuit, a 115 volt potential exists from the "R" terminal to ground through a possible short in the capacitor. However, from the "S" or start terminal, a much higher potential, possibly as high as 400 volts, exists because of the counter EMF generated in the start winding. Therefore, the possibility of capacitor failure is much greater when the identifi ed terminal is con- nected to the “S" or start terminal. The identifi ed terminal should always be connected to the supply line, or "R" terminal, never to the "S" terminal.
When connected properly, a shorted or grounded run-
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