Commissioning - Danfoss VCH115 Application Manual

Scroll compressors, VCH115 | Application
• For the initial charge, the compressor must not run.
• Charge refrigerant as close as possible to the nominal system charge.
• This initial charging operation must be done in liquid phase between the condenser outlet and the lter drier.
If needed, a complement of charge can be done, in liquid phase while compressor is running by slowly throttling
liquid in.
Never bypass safety low pressure switch.
For more detailed information see "Recommended refrigerant system charging practice" AP000086421422.
Dielectric strength and insulation resistance tests
The tests are performed on each compressor and frequency converter in the factory, so it is not necessary and not
recommended to do often Hipot test (dielectric withstand test) as it may damage the motor or frequency convertor.
If a Hipot test has to be done anyway, following instructions must be followed.
Motor:
• 1800VDC (for code G) for 1 seconds must be applied; Further reduce test voltage if do more Hipot test.
• The current leakage must be below 5mA.
Drive:
• Compressor not connected.
• R, S, T, U, V, W Terminals must be shortened and connected to high voltage terminal of the testing device, refer to
the picture.
• DC voltage 2100V.
• Ramp up time 3 seconds, Full DC voltage must be established 2 seconds.
• The current leakage during the test must be below 10mA.
• Ramp down time to 0V in 25 seconds.
When conducting a high voltage test make sure the system is not under vacuum, this maybe cause electrical motor
failure.
U
MOTOR
Do not use a megohm meter nor apply power to the compressor while it is under vacuum as this may cause
internal damage.

Commissioning

Preliminary check
Check electrical power supply:
© Danfoss | Climate Solutions | 2023.08
V W PE
MOTOR
R S T
NET
NET
On M Ohm 2000 M Ohm
2 20 200 2000MOhm
+ 20 ohm
- M ohm
Gossen - ISOWID - 0413
AB392939083370en-000202 | 47
M ohm
V
Ohm
CC-000214