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© Munters Corporation, January 2020
QM1086r8
Electrical Wiring
3.
All wiring should be installed in accordance with National, State, and Local electrical codes. Fans used to ventilate
livestock buildings or other rooms where continuous air movement is essential should be connected to individual
electrical circuits, with a minimum of two circuits per room. For electrical connection requirements, refer to diagram
on motor nameplate and to information enclosed with the Munters environmental control to be used. After wiring
check for proper motor rotation.
Single Phase Fans
: motor overload protection should be provided for each fan. A Circuit Breaker Switch or slow
blow motor type fuses must be used,
See Figure 12A. See form QM1400 for proper size
.
Three Phase Fans
: motor overload protection should be provided for each fan. A three-pole motor starter or slow
blow motor fuses must be used.
See Figure 12B
.
If a frequency drive (inverter) is used, confirm that motors are rated for inverter duty at the voltage used. Shielded
power cable between frequency drive and each motor is highly recommended. Installation of line reactors is
recommended to reduce voltage spikes and harmonic distortion. Supplemental motor overload protection is also
recommended.
NOTE
: A safety cut-off switch should be located adjacent to each fan.
Figure 12A
Single Phase - Motor Overload Protection with Disconnect
(SY2000 or Equivalent)
120 or 240 VAC
Power Supply for
Fan
L1 (H)
L2 (N)
G
T1 (H)
T2 (N)
G
120 or 240 VAC
Power Out
to Fan
L1 (H)
L2 (N)
T1 (H)
T2 (N)
KEY:
L1=Line 1
L2=Line 2
L3=Line 3
H=Hot
N=Neutral
G=Ground
NOTE:
Information in parenthesis refers to 120 VAC control.
Three Phase
Power Supply for
Fan
L1
L2
G
T1
T2
G
Three Phase
Power Out
to Fan Motor
L1
L2
T1
T2
L3
T3
L3
T3
Figure 12B
Three Phase - Motor Overload Protection with Disconnect
Safety cut-off
switch
Motor Starter
Circuit Breaker Switch