Nominal Capacitor Value And Relays - Danfoss MLM Series Application Manuallines

Application Guidelines
CSR wiring
Nominal capacitor value
and relays
Compressor models
MLZ/MLM015
MLZ/MLM019-021-026
220-240 V /1/50 Hz
Motor voltage code 5
MLZ/MLM030
MLZ/MLM038-042
MLZ/MLM015
MLZ/MLM019-021
208-230 V / 1 / 60 Hz
Motor voltage code 1
MLZ/MLM026
MLZ/MLM030
not provided with the
compressor
MLZ/MLM038
MLZ/MLM042
Electrical data, connections and wiring
remains at high temperature and thus at high
resistance as long as power is connected to the
compressor. When the compressor is switched
off, the PTC cools down to its initial low resistance
and becomes available to support the next
compressor start.
It is important to provide sufficient time between
motor starts to allow the PTC to cool down
close to ambient temperature. Depending on
the ambient conditions and the cooling of the
PTC, this may take about 5 minutes. A restart
before the PTC is back to low resistance may be
successful or the motor may stall in a locked-rotor
state depending on the ambient and system's
conditions. A locked-rotor state causes the
Model
MLZ/MLM015
MLZ/MLM019
MLZ/MLM021
MLZ/MLM026
MLZ/MLM030
MLZ/MLM038
MLZ/MLM042
Note: MLZ compressors with PTCSCR are not approved by UL. It is the customers' responsibility to get final approval for the system
when required.
CSR wiring provides additional motor torque
at start-up, by the use of a start capacitor in
combination with the run capacitor. The start
capacitor is only connected during the starting
operation, a potential relay is used to disconnect
it after the start sequence.
Some applications with high differential pressure
and start duty as "soft serve ice cream machine"
can require CSR wiring. This configuration
can also be used to reduce erratic starting
at unfavourable conditions such as very low
ambient temperature or weak voltage.
Default solution: PSC wiring
with run capacitor only
PSC wiring
Run capacitor
internal protector to open and would cause even
further delay until the overload is reset.
The following PTC types are recommended for
the MLZ/MLM single phase compressors:
N
Thermostat
Voltage code 1
208-230 V/1~/60 Hz
305C12*
305C9* / 305C11*
305C9* / 305C11*
305C12*
305C9* / 305C11*
305C9* / 305C11*
305C9* / 305C11*
N
Thermostat
Additionnal components for CSR wiring
Start capacitor
µF µF
40 145-175
70 145-175
50 161-193
55 88-108
45 145-175
45 145-175
60 88-108
70 161-193
55 88-108
80 189-227
L
Run capacitor
PTC
Voltage code 5
220-240 V/1~/50 Hz
305C9* / 305C11*
305C9* / 305C11*
305C9* / 305C11*
305C9* / 305C11*
305C9* / 305C11*
305C9* / 305C11*
305C9* / 305C11*
L
Start Relay
5
2
Run capacitor
1
Start capacitor 15 kΩ -1 w
CSR wiring
Relay
Reference
3ARR3*3AL*
3ARR3*3AL*
3ARR3*24AP*
3ARR3*25AS*
3ARR3*3M*
3ARR3*3M*
3ARR3*3L*
3ARR3*3L*
3ARR3*25AS*
3ARR3*3L*
FRCC.PC.015.A8.02
C
IOL
S R
C
S R
RVA9CKL
RVA9CKL
RVA3EKL
RVA4GKL
RVA2ACKL
RVA2ACKL
RVA2ABKL
RVA2ABKL
RVAA4IKL
RVA2ABKL
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