Compressor Electrical; Compressor; Ptc-Starter/Combo - Kenmore 795.78302.800 Service Manual

4.

COMPRESSOR ELECTRICAL

4-1 COMPRESSOR

4-1-1 Role
The compressor intakes low temperature and low pressure
gas from the evaporator of the refrigerator and compresses
this gas to high temperature and high pressure gas. It then
delivers the gas to the condenser.
4-1-2 Composition
The compressor includes overload protection. The PTC
starter and OLP (overload protector) are attached to the
outside of the compressor. Since the compressor is
manufactured to tolerances of 1 micron and is hermetically
sealed in a dust and moisture-free environment, use extreme
caution when repairing it.
4-1-3 Note for Usage
(1) Be careful not to allow over-current.
(2) If compressor is dropped or handled carelessly, poor
operation and noise may result.
(3) Use proper electric components appropriate to the
particular compressor in your product.
(4) Keep compressor dry.
If the compressor gets wet (in the rain or a damp
environment) and rust forms in the pin of the Hermetic
Terminal, poor operation and contact may result. If the
hermetic connector rusts out or fails, refrigerant and oil will be
expelled into the contact area, probably resulting in smoke
and fire.
(5) When replacing the compressor, be careful that dust,
humidity, and soldering flux don´t contaminate the inside of
the compressor. Contamination in the cylinder may cause
noise, improper operation or even cause it to lock up.
4-2 PTC-STARTER/ COMBO
4-2-1 Composition of PTC- Starter
(1) PTC (Positive Temperature Coefficient) is a no-contact
semiconductor starting device which uses ceramic material
consisting of BaTiO .
3
(2) The higher the temperature is, the higher the resistance
value. These features are used as a starting device for the
motor.
4-2-2 Role of PTC-Starter
(1) The PTC is attached to the Sealed Compressor and is
used for starting the motor.
(2) The compressor is a single-phase induction motor. During
the starting operation, the PTC allows current flow to both the
start winding and main winding.
4-2-3 Combo TSD
TSD (Time Starting Device) is a new electronic starting
system for high efficiency compressors due to the following
characteristics:
(1) Combo concept-overload protector, electronic board and
cover in a single casing.
(2) Fully electronic concept.
(3) Full integration of starting and protection devices.
(4) Free from mechanical and electromagnetic noises.
4-2-4 Role of Combo TSD
(1) The combo is attached to the sealed compressor and is
used for the operation and protect the motor.
(2) The compressor is a single phase induction motor. During
the starting and operation, the combo allows current flow to
both the start and main winding.
4-2-5 PTC/Combo - Applied Circuit Diagram
Starting Method for the Motor
PTC DIAGRAM
OVERLOAD PROTECTOR
N
PTC
2
3
L1
PTC STARTER
Resistance Starter Capacitor Running
COMBO DIAGRAM
COMPRESSOR
MOTOR
M S
SEALED
TERMINAL
4-2-6 Motor Resarting and PTC/ Combo Cooling
(1) It requires approximately 5 minutes for the pressure to
equalize before the compressor can restart.
(2) The PTC/Combo device generates hea during operation.
Therefore, it must be allowed to cool before the compressor
can restart.
4-2-7 Relation of PTC-Starter / Combo and OLP
(1) If the compressor attempts to restart before the
PTC/Combo device is cooled, the PTC/Combo device will
allow current to flow only to the main winding.
(2) The OLP will open because of the over current condition.
Thissame process will continue (3 to 5 times) when the
compressor attempts to restart until the PTC/Combo device
has cooled. The corret OLP must be properly attached to
prevent damage to the compressor.
Parts may appear physically identical but could have different
electrical ratings. Replace parts by part number and model
number. Using an incorrect part could result in damage to the
product, fire, injury, or possibly death.
- 13 - -
C
COMPRESSOR
5
MOTOR
M
S
M
S
6
SEALED
TERMINAL
C
S M
L
OLP
LINE
PTC
N