Electrolux BEVERAGE CENTER II, Service Manual

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24
ELECTRICAL COMPONENTS
ELECTRICAL GROUNDING
All refrigerators are equipped with a power supply cord
incorporating a three-prong grounding plug and a
ground wire which is attached to the refrigerator cabinet
for protection against shock hazard. Each electrical
component is either cabinet mounted or connected
through a ground wire to the cabinet to complete the
ground. Certain components, such as defrost timers,
may be double insulated and do not require a ground
wire.
Ensure that the electrical wall receptacle is of the three
prong type and is properly grounded in accordance with
the National Electrical Code and/or local codes.
COMPRESSOR ELECTRICAL COMPONENTS AND
CIRCUITS
The new series of very high efficiency compressor is
equipped with all new electrical components consisting
of a solid state PTC relay with a thermally operated
overload protector, and a run capacitor. (See Figure C1)
Solid State Relay
The solid state relay has no moving parts. It consists of
a PTC resistor mounted in a plastic case with
appropriate terminals. PTC (Positive Temperature
Coefficient) simply denotes a resistor which increases
in resistance as its temperature is increased. The self-
heating PTC resistor used in the solid state relay has the
unique characteristic of changing from low to very high
resistance very abruptly, thus serving as an ON-OFF
switch. (See Figure C3)
The solid state relay plugs directly onto the compressor
start and run terminals. (See Figure C2) Relay terminals
1, 2, and 5 are connected within the relay, as are terminals
3 and 6.
Figure C1
A run capacitor is connected to relay terminals 2 and 3,
so it is connected in parallel with the PTC resistor. One
side of the 120 VAC power is connected to relay terminal
1. The other side of the line is connected to the overload
protector. (See figure C3.)
Figure C2
To Check/Replace Relay
1. Disconnect electrical supply to refrigerator.
2. Remove bale wire holding relay to compressor.
(See Figure C2)
3. Remove relay assembly from compressor.
(See Figure C2)
4. Use small, flat-bladed screwdriver to disconnect
leads to relay assembly.
5. Use flat-bladed screwdriver to gently pry capacitor
from relay assembly.
6. Use ohmmeter to check resistance between
terminals 5 and 6. Resistance should be 3 to 12
ohms, at normal room temperature. Shorted relay
will read 0 ohms. Open relay will read very high or
infinite resistance.
Figure C3
NOTE : There are two Exploded View Diagrams
(Cabinet and System) at the end of this section,
pages ??, to assist you in troubleshooting.
Figure C2