Controls And Relays; Control Board - Hoshizaki F-330BAH Service Manual

III. Controls and Relays
The F-330BAH(-C) is controlled by a control board and 5 relays. X1 and X2 relays are
located on the control board and control GM, Comp, and FM operation. X10, X11, and
X12 relays are independent relays located in the control box. X10 relay controls the
icemaking process and DV operation. X11 relay controls WV operation, GM ice purge
timer, and low water safety circuit. X12 relay controls EH operation (-C models), Comp
delay timer, and DV operation.
A. Control Board
The control board operates on 24VAC provided at CB #1 (W/R) and #2 (LBU). There are
three 35VDC circuits that open/close to control operation.
1. Control Board 35VDC Circuits:
1–Water confirmation for GM activation. X11 relay terminals #4 (DBU) and #6 (BR)
must close to complete the CB 35VDC circuit between CB #3 (BR) and #4 (DBU).
Once this circuit closes, CB energizes X1 relay and GM starts. If open longer
than 90 sec., appliance shuts down.
2–Jumper. The jumper between CB #5 (P) and #6 (P) must be in place for CB
operation.
3–Gear Motor confirmation and 90 sec. Comp delay timer initiation. X12 relay
#4 (W/BK) and #6 (W/O) must close to complete the CB 35VDC circuit between
CB #10 (W/BK) and #11 (W/O). Once this circuit closes, 90 sec. Comp delay
timer starts. When 90 sec. Comp delay timer terminates, CB energizes X2 relay,
energizing Comp and FM.
2. Control Board Relays:
X1- Gear Motor Relay: X1 relay energizes after the reservoir fills, UFS closes
energizing X11 relay. Once energized, X11 relay closes a 35VDC circuit between
CB terminals #3 (BR) and #4 (DBU). Once CB 35VDC circuit closes between
terminals #3 (BR) and #4 (DBU), X1 relay energizes, energizing GM and
X12 relay.
X2- Compressor Relay: X2 relay energizes after CB 90 sec. Comp delay timer
terminates. CB 90 sec. compressor delay timer starts after X12 relay energizes
and closes a 35VDC circuit between CB #10 (W/BK) and #11 (W/O).
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