12
requires shutdown of the booth fans. Breaking the
circuit at that point will shut down all booth
operations. The 120v continues through the EM
(emergency) stop switch in the remote control panel,
and NC overload contacts of each Motor Starter. The
120v is then present at the light switch,
off/spray/bake switch, and bake timer. If either
motor trips to an overload condition, a RED light for
the respective motor is lit, and all booth operations
quit. Breakers protect both control voltages, 110v
and 24v.
The EM switch, when depressed, shuts down all
both operations. Turning the EM switch clockwise
reconnects the supply voltage, unless the jumper
circuit for the fire suppression system is open.
SPRAY MODE:
When the green power light is lit, placing the OFF-
SPRAY-BAKE switch in the spray position begins
the Spray Mode. The booth will operate in SPRAY
mode indefinitely. The operator must shut off the
booth, or switch to the Bake Mode. The SPRAY
position provides 120v to the PLC (Programmable
Logic Controller) and shows input “0” on the PLC
input display. This in turn provides 110v to starter
SM2 located in the Control Panel. SM2 controls the
Exhaust Motor and shows as “10” on the PLC output
display. The green light for the exhaust motor on the
Control Panel should be lit. A time sequence is also
started in the PLC as SM2 is energized. At the end of
the time sequence, 110v power is provided to SM1
and the Temperature Controller and shows as “9” on
the PLC output display. SM1 controls the intake
motor and provides 120v to the green light for the
intake motor and the BURNER switch. The
temperature controller should show display and go
through its’ boot operations. All are located on the
remote control panel.
If the BURNER switch is in the WINTER position,
120v power is provided to the PLC and shows as “3”
on the PLC input display, which in turn provides
110v to the gas train power circuit shown as “7” on
the PLC output display. See the text of the Gas
Train Power Circuit. If the BURNER switch is in
the SUMMER position, the Gas Train Power
Circuit will not be energized as there will be
no input to the PLC.
BAKE MODE:
Place the OFF-SPRAY-BAKE switch in
BAKE provides 120v to the PLC and shows as
“1” on the PLC input display. The PLC will
perform a time sequence then power is applied
to the Bake Timer located on the Remote
Control Panel, the change over damper
solenoid and relay RP in the main control
panel. This places the booth in Bake Mode.
The timer will begin timing. The Bake Timer
should be set in its’ “C” mode, on the left of
the timer face, and “M” for minutes, on the
right.
When the Change over damper solenoid is
energized, the changeover damper is opened
pneumatically releasing the Damper Position
Valve. When released, the pressure switch
(RA) connected to the Position Valve de-
energizes input to the PLC shown as “11” on
the PLC input display. This disconnects 110v
power to the compressed air solenoid, shown
as “5” on the PLC output display, and
eliminates the 120v circuit to RL contactor,
turning off the booth lighting. If the burner
switch is in the summer position, the PLC will
give 120v to the gas train circuit. The (RP)
relay closes the second set point loop on the
temperature controller. This sets the
temperature controller to the second set point
or starts the sequence of multiple temperature
settings on a multi-set point controller
(optional).
At the completion of the bake time, the Bake
Timer stops timing and gives 120v input to the
PLC shown as 14 on the PLC input display.
This begins the Cool Down time sequence
(Shutdown mode).
SHUTDOWN MODE:
