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Discharge line thermostats - available from Copeland - will provide adequate temperature
protection in fixed applications.
Install the thermostat approximately 120 mm from the discharge valve outlet.
Figure 9
In order to avoid improper functioning due to false readings, this thermostat needs to be
insulated.
4.7
Motor protection
Conventional inherent internal line break motor protection is provided with all compressor
models covered in this guideline.
The protector reacts to a combination of motor current and motor winding temperature. The
internal protector protects against single phasing. Time must be allowed for the motor to cool
down before the protector will reset.
4.8
High potential testing
WARNING
Conductor cables! Electrical shock! Shut off power supply before high-
potential testing.
CAUTION
Internal arcing! Motor destruction! Do not carry out high-voltage or
insulation tests if the compressor housing is under vacuum.
Copeland subjects all scroll compressors to a high-voltage test after final assembly. The test is
carried out according to EN 0530 or VDE 0530 part 1. Since high-voltage tests lead to premature
aging of the winding insulation further additional tests of that nature are not recommended.
A high-potential test is usually conducted on the production line by the manufacturer. This test
can be conducted in the field; however, field technicians typically do not have the required
equipment.
Copeland Horizontal Scroll
the pumping components. As a result, the motor can be immersed in oil and refrigerant to a
greater extent than hermetic reciprocating compressors when liquid refrigerant is present in the
shell. In this respect, the horizontal scroll is more like semi-hermetic compressors which can
have horizontal motors partially submerged in oil and refrigerant. When Copeland Scroll
compressors are Hipot tested with liquid refrigerant in the shell, they can show higher levels of
current leakage than compressors with the motor on top. This phenomenon can occur with any
compressor when the motor is immersed in refrigerant. The level of current leakage does not
present any safety issue. To lower the current leakage reading, the system should be operated
for a brief period of time to redistribute the refrigerant to a more normal configuration and the
system should be Hipot tested again. See AE Bulletin 4-1294 for Megohm testing
recommendations. Under no circumstances should the Hipot test be performed while the
compressor is under a vacuum.
C6.2.7/0302-1007/E
TM
compressors are configured with the motor at the same level as
TM
11
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