Danfoss MLZ Evolution A, Application Manuallines

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Electrical data, connections and wiring
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.
CSR wiring
Nominal capacitor value
and relays
Model
Voltage code 5
220-240 V/1~/50 Hz
MLZ015 305C9* / 305C11*
MLZ021 305C9* / 305C11*
MLZ026 305C9* / 305C11*
MLZ030 305C9* / 305C11*
MLZ038 305C9* / 305C11*
Note: MLZ compressors with PTCSCR are not approved by UL. It is the customers’ responsibility to get final approval for the system
when required.
N L1
Thermostat
Start capacitor
Start Relay
5
2
1
15 kΩ -1 w
C
S R
Run capacitor
Compressor models
Default solution: PSC wiring
with run capacitor only
Additionnal components for CSR wiring
PSC wiring CSR wiring
Run capacitor Start capacitor Relay
µF µF Reference
220-240V / 1 /50Hz
Motor voltage code 5
MLZ015 40 145-175 3ARR3*3AL* RVA3EKL
MLZ019-021-026 70 145-175 3ARR3*3AL* RVA3EKL
MLZ030 50 161-193 3ARR3*24AP* RVA3EKL
MLZ038-042 55 88-108 3ARR3*25AS* RVA4GKL
208-230V / 1 / 60Hz
Motor voltage code 1
not provided with the
compressor
MLZ015 45 145-175 3ARR3*3M* RVA2ACKL
MLZ019-021 45 145-175 3ARR3*3M* RVA2ACKL
MLZ026 60 88-108 3ARR3*3L* RVA2ABKL
MLZ030 70 161-193 3ARR3*3L* RVA2ABKL
MLZ038 55 88-108 3ARR3*25AS* RVAA4IKL
MLZ042 80 189-227 3ARR3*3L* RVA2ABKL
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 internal protector to open and would cause
even further delay until the overload is reset. The following PTC types are recommended for
the MLZ single phase compressors:
N L1
Run capacitor
PTC
Thermostat
C
S R
IOL
AB243286444663en-001003
18
Application Guidelines