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AGL_Ref_ST_YBK1E_EN_Rev01
Figure 16: IP54 T-Box and correct electrical installation with cable gland
4.4
Motor insulation
The motor insulation material is class "B" (P
F
ZN/T
F
MN) within maximum allowable operating
temperatures according to IEC 34-1 or DIN 57530.
4.5
Motor protection
Independently from the internal motor protection, fuses must be installed before the compressor. The
selection of f uses has to be made according to EN 60269-1 or EN 60204-1 and compressor
maximum operating current (MOC). Not installing f uses bef ore the compressor or selecting
inappropriate fuses may result in compressor failure.
Conventional inherent internal line break motor protection is provided f or the YB*K1E range of
compressors.
4.6
High-potential testing
WARNING
High-potential testing in a flammable atmosphere! Fire hazard!
For
systems using A2L ref rigerant, make sure the atmosphere is non-flammable
bef ore performing high-potential testing. DO NOT perf orm any high-potential
test when the compressor is charged with flammable refrigerant.
WARNING
Conductor cables! Electrical shock hazard!
Shut of f power supply before
high-potential testing.
CAUTION
Internal arcing! Motor destruction!
Do not perform high-voltage or insulation
tests if the compressor housing is under vacuum.
Emerson subjects all scroll compressors to a high-voltage test after f inal assembly. Each motor
phase winding is tested according to EN 60034-1 at a dif ferential voltage of 1000 V plus twice the
nominal voltage.
Since high-voltage tests lead to premature ageing of the winding insulation, f urther additional tests
of that nature are not recommended. However, if it has to be done f or any reason, it shall not be
made with the compressor charged with refrigerant. Run the test with a lower voltage, as described
above. Disconnect all electronic devices, eg, motor protection module, fan speed control, etc prior to
testing.
Special attention should be paid when perf orming a high-potential test and reading the Megohm
resistance on A2L compressors, as such tests can induce an electrical arc and cause a fire hazard.
For the same reason, compressors removed f rom a system with A2L ref rigerant will need to have
the oil drained and a nitrogen purge introduced to f lush any remaining ref rigerant f rom the
compressor prior to high-potential testing and Megohm resistance reading.
