Phason
MSC-4 user manual
10440007
1
MSC-4 user manual
The Manual Speed Control (MSC-4) is a simple and effective way to control fan motors. The MSC-4 allows you to manually
adjust the speed of ventilation and heat exchanger equipment. The MSC-4 can also be used as a light dimmer for brooder heat
lamps and can power up to five 250-watt lamps.
Features
One variable stage output
ON/OFF switch
Adjustable HIGH/LOW settings
Overload protection fuse
Rugged enclosure (corrosion resistant, water
resistant, and fire retardant)
CSA approval
Two-year limited warranty
Electrical ratings
Input:
120/230 VAC,
50/
60 Hz
Variable: 12.5 A at 120/230 VAC, general-purpose (resistive)
9 FLA at 120/230 VAC, PSC motor
1/2 HP at 120 VAC, 1 HP at 230 VAC, PSC motor
1500 W tungsten at 120 VAC
Fuse:
15 A, 250 VAC ABC-type ceramic
The MSC-4 is designed for high current and is too strong for small motors. The MSC-4 might not operate
properly when running fan motors with a very inductive power factor and that draw less than 0.5 A.
To test for this problem, connect the control to the motor and adjust the control from minimum to maximum. If
the motor jerks or locks during any part of the range of operation, the current draw is too low.
Adding more motors in parallel to increase the current draw will solve the problem. If this is not a viable
solution, an 8.5 A version (MSC-4-8.5) is available from your dealer.
Variable speed fan motors can draw up to 30% more current at reduced speeds than maximum speed. Fan
motor specifications show current draw at maximum speed. Current over 12.5 A will cause overheating and
eventual failure of the MSC-4 control. Check current requirements for the fan motor by either measuring
current draw at all speeds or consulting the dealer for information about that fan.
Fill out the information below to help verify that you do not exceed the electrical ratings of the MSC-4.
Fans
A
Max. current draw per fan
B
Number of fans
A × B =
Total current draw
Make
Model
Voltage rating
Power factor
Lamps
C
Watts per lamp
D
Number of lamps
C × D ÷ 120 V =
Total current draw
