Electrical Data, Connections And Wiring; Supply Voltage; Compressor Electrical Speci Cations; Lra (Locked Rotor Amp) - Danfoss VRJ Application Manuallines

Application Guidelines

Supply Voltage

Compressor electrical
speci cations

LRA (Locked Rotor Amp)

MCC (Maximum Continuous
Current)

Winding resistance

8
AB141686422149en-US0401

Electrical data, connections and wiring

Nominal voltage 208-230V – 1Ph – 60Hz
Voltage range 187 – 253 V
Compressor model
VRJ028
VRJ035
VRJ044
LRA is the higher average current as measured
on a mechanically blocked compressor tested
under nominal voltage. LRA is printed on the
nameplate, according to UL requirements. With
The MCC value is the maximum at which
the compressor can be operated in transient
conditions and out of the operating envelope. The
VRJ scroll compressors are equipped with an IPM
(permanent magnet) motor.
Winding resistance is the resistance between
indicated terminal pins at 77°F (resistance value ±
7%).
Winding resistance is generally low and it requires
adapted tools for precise measurement. Use
a digital ohm-meter, a '4 wires' method and
measure under stabilised ambient temperature.
Winding resistance varies strongly with winding
VRJ compressors must not be connected directly
to the mains supply. They must only be powered
through the dedicated Danfoss variable speed
drive.
Compressor model
VRJ028
VRJ035
VRJ044
Refer to "Danfoss VRJ Installation and Operation
instructions" for more details about supply
voltage.
LRA MCC
A A
10.2 18
12 23.5
12 30
VRJ compressors, the LRA value is low because the
variable speed drive reacts very rapidly (far below
1 second).
MCC value is measured based on UL conditions
(max load) and at low voltage.
temperature ; If the compressor is stabilised at a
di erent value than 77°F, the measured resistance
must be corrected with following formula:
a + t
R = R
a + t
tamb 77°F
t : reference temperature = 77°F
77°F
t : temperature during measurement (°F)
amb
R : winding resistance at 77°F
77°F
R : winding resistance at t
tamb
a: Coe cient a= 390
Variable Speed Drive Model
176L0767
176L0766
176L0765
Winding resistance
Ohm
0.296
0.254
0.254
amb
77°F
amb