Honeywell AUTOMATIC CONTROL Engineering Manual page 101

Any time the Supply Fan 1M runs, the Return Fan 2M runs.
Any time the Return Fan 2M runs, the Exhaust Fan 3M
and the ventilation controls are energized by the After-Hours
X2-1 X1-1
X1-1
H
SUPPLY
A
X1-2
H
A
X1-3
H
A
H
INTERVAL TIMER
(AFTER HOURS)
480V
X2-2 X1-2
1M
EXHAUST
FAN
SMOKE
LOW
DETECTOR
TEMPERATURE
RETURN
THERMOSTAT
1M
FIRE
EXHAUST
120 VOLT CONTROL CIRCUIT
2TC
1CR
Fig. 75. Start-Stop Control.
PNEUMATIC CONTROL FUNDAMENTALS
Interval Timer or by the Occupancy Schedule Time Clock
2TC set for 0750.
Both Clocks 1TC and 2TC are set to shut the system down
at 1700.
480V
X2-3
2M
EXHAUST
FAN
HIGH STATIC
PRESSURE
CUTOUT 1TC
1CR
TN
NIGHT
'STAT
2CR
EARLY START CLOCK
TIME CLOCKS
OCCUPANCY CLOCK
2M
2CR
91
ENGINEERING MANUAL OF AUTOMATIC CONTROL
480V
X1-3
3M
EXHAUST
FAN
X2-1
OL
1M
1M
2EP
X2-2
OL
2M
2M
X2-3
OL
3M
3M
N
1
TC
2
TC
1
CR
2
CR
1EP
M10303