Honeywell AUTOMATIC CONTROL SI Edition User Manual

ELECTRIC CONTROL FUNDAMENTALS
ENGINEERING MANUAL OF AUTOMATIC CONTROL
117
TRANSFORMER
OFF
HAND
OL
2M
C2541-1
STARTER
FUSED
DISCONNECT
2M
OL
T1
2M
2M
AUTO
SUPPLY FAN
AIRFLOW SWITCH
OL
OL
T2
T3
L3
L2
L1
F
F
F
F
RETURN
FAN
MOTOR
TRANSFORMER
STOP
START
OL
1M
STARTER
FUSED
DISCONNECT
1M
OL
T1
1M
1M
1M
OL
OL
T2
T3
L3
L2
L1
F
F
F
F
SUPPLY
FAN
MOTOR
FS
RELAY
INTERLOCK TO ENERGIZE
TEMPERATURE CONTROLS
HAND/OFF/AUTO SWITCH
MOTOR CONTROL
PUSH-BUTTON START-STOP
MOTOR CONTROL
CONTROL COMBINATIONS
There are many different control combinations for motor
control circuits. Figure 38 illustrates a return fan interlocked
with the supply fan. In this circuit, the supply fan starts when
the START button is pressed energizing starter solenoid 1M.
The return fan will not start until supply airflow is proven. A
relay can be added to interlock to the temperature control
system. An auxiliary contact on the supply fan starter, when
available, can be used for this same function.
Fig. 38. Typical Interlock of Supply and Return Fans.

Honeywell AUTOMATIC CONTROL SI Edition Specifications

General

Brand	Honeywell
Model	AUTOMATIC CONTROL SI Edition
Category	Control Systems
Language	English