I.C.E. 3 OSDs - Manual (Page 16)

15
RECIRCULATION SEQUENCE OF OPERATION
PB4000 REMOTE PANEL c/w PROGRAMMABLE LOGIC CONTROLLER (PLC)
Spray Mode
1. Three-position damper is powered continuously. Lighting Contactors are always energized as long as main
disconnect is on and Booth Lights Switch is in “ON” position. Spray Gun Solenoid (by others) is energized only in
Spray Cycle.
2. System “ON” Push Button is pressed and released, energizing and supplies power to the Maxitrol Amplifier. Three
position damper motor opens the damper to 100% fresh air.
3. When the fresh air damper motor end switch is engaged, the High Speed Exhaust (Spray) Fan Starter is energized
and closes the High Exhaust Fan Air Proving Switch.
4. Delay Exhaust Start Timer (Set to 4 seconds) is energized.
5. After 4 seconds the Supply Fan Motor Starter Coil is energized, Spray Cycle Light and Supply Fan Light are
energized.
Dry Mode
Note: A set of normally closed contacts from a fire alarm are placed in series with PLC Input No. 4 so that in the event
of a fire the Dry Cycle is shut down and the system reverts back to the Spray Cycle venting smoke to the outdoors
through the unit.
1. Dry Mode Push Button is pressed and released. Spray Cycle Light is de-energized and Spray Gun Solenoid (by
others) is de-energized. Burner is still active discharging at 75 °F.
2. Purge Cycle Timer (set to 180 seconds, adjustable from Operator Interface) is energized while simultaneously
energizing the Purge Cycle Light.
3. After 180 seconds, the Purge Cycle Light is de-energized. The Dry Timer (set to paint specifications, adjustable
from Operator Interface ) is energized which will energize the Spray/Dry Switch Over Timer (set to 10-20 seconds),
relay R1, and the Dry Cycle Light.
4. After 10-20 seconds, the contacts on the Maxitrol Amplifier switch to set point 2 (preheat).
5. When R1 relay is energized, the three position damper motor travels the damper to the mid-position. The damper
motor end switch de-energizes the High Speed Exhaust Fan Starter.
6. The High Exhaust Fan Air Proving Switch drops out, the Low Exhaust Speed Fan Air Proving Switch makes and the
Season Switch is disabled.
7. After 120 seconds the contacts on the Maxitrol amplifier switch to set point 3 (drying).
8. Expiration of the paint specification dry time, Dry Cycle Light, Spray/Dry Switch Over Timer, and relay R1 are de-
energized.
9. The three position damper returns to 100% fresh air.
Cool Down Mode
1. The three position damper motor is energized opening the fresh air damper to 100%.
2. The exhaust fan reverts back to high speed.
3. The unit will run on the low temperature setting (set point 1) and high cfm until the Cool Down Time has expired.
4. On expiration of the cool down time the unit shuts down.
Timer Settings
TD-1 Delay Exhaust Start Timer 4 Seconds (in PLC)
TD-2 Low Fire Delay Timer 20 Seconds (in unit panel)
TD-3 Purge Cycle Timer 180 Seconds (in PLC, Operator Programmable)
TD-5 Spray/Dry Switch Over Timer 10-20 Seconds (in PB3000 Panel)
TD-6 Dry Mode Preheat Timer 120 Seconds (in PLC)
Dry Timer set as per Paint Specifications (in PLC, Operator Programmable)
Limit Settings
High Limit Spray = 165
°F, High Limit Dry = 200°F