Electrical Checkout; Overload Check; Compressor Check; Capacitor Check - Cornelius CMP600–30A Service Manual

ELECTRICAL CHECKOUT

1. Be sure the unit is disconnected from the power source. Remove the compressor electrical box cover. Check
for obvious damage and loose wires.
2. Disconnect the fan motor leads. Since capacitors store energy, short the capacitor with a screwdriver. This will
prevent shocks.
3. Disconnect the compressor terminal wires.
OVERLOAD CHECK –
4. Using a volt–ohm meter check the continuity across the overload, contacts #1 & #3. If none, wait for unit to
cool down and try again. If still no continuity, the overload protector is defective and should be replaced.
COMPRESSOR CHECK –
The resistance readings on the windings will be between 0.25 and 10.00 ohms, a meter capable of these low
readings must be used.
5. Check between "C" & "R." Replace compressor if there is no continuity as the run windings are open.
6. Check between "C" & "S." Replace the compressor if there is no continuity as the start windings are open.
Check between "C" & "R", or "S" and shell of the compressor. If there is continuity replace
7.
the compressor as the motor is grounded.
8. Check between screw terminal on the overload and "C" on the compressor. Check and repair the lead or
connections if there is no continuity.

CAPACITOR CHECK

9. Check or replace start capacitor, disconnect bleed resistor before checking for shorted capacitor.
10. Check or replace run capacitor (if supplied) check or shorted capacitor or either terminal grounded to case.

FIGURE 10. ELECTRICAL BOX

(See Figure 5)
(See Figure 10)
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