24
Electrical control system operation
The wiring diagrams which follow illustrate the circuitry of Follett ice machines used with ice dispensers. Both
normal operation of the ice machine (Stages 1 - 6) and non-normal diagnostic sequences showing torque-out (Stages
7 - 10) for use in troubleshooting ice machine problems are shown.
Follett ice machines used on top of an ice storage bin have a slightly different circuitry. The operational and diagnostic
stages for these ice machines will be otherwise the same as Stages 1 - 10 that follow.
Circuitry notes
When the ice machine is used with a dispenser it receives power from two sources – the main power supply and
the bin control signal power from the dispenser. Disconnect both power sources before performing service. When
performing electrical service, always use a meter to determine whether or not the components being serviced are
energized.
High pressure cutout opens at 29 bar (425 PSI) and closes at 20 bar (287 PSI) (auto reset).
Compressor switch should read open in on position.
Compressor start relay is position sensitive. See label on start relay for proper orientation.
Flashing water LED at any time indicates that water signal to board had been lost for more than
one second.
Ten-second delay: There is a 10 second delay in reaction to loss of water (WTR) or bin (B-E) signals. If signals are not
lost for more than 10 seconds, no reaction will occur.
Normal operation – Stage 1
Power is supplied to L1 of the control board. The ice level control in the dispenser is closed and calling for ice,
completing the bin signal circuit to the control board. The control board will now go through the start-up sequence.
Less than 30 seconds will elapse as the water sensor located in the fl oat reservoir checks for water in the reservoir.
The bin empty LED (B-E), and power LED (PWR) will be on.
WHITE
BLACK
YELLOW
WHITE
4
3
2
START
RUN
GEARMOTOR
COMPRESSOR
POTENTIAL
START RELAY
RUN
CAP.
START
CAPACITOR
WATER
SENSOR
BIN
T-STAT
BIN SIGNAL
SWITCH
COMPRESSOR
SWITCH
HIGH PRESSURE
SAFETY SWITCH
BLACK
ORANGE
FAN
BLACK
BLACK
BLACK
BLACK
RED
ORANGE
BLACK
BLACK
WHITE
WHITE
BLUE
BROWN
GRN IN
ELEC BOX
GREEN/YELLOW
RED
DRV
FAN
COMP
POWER
BLACK
BLUE
BLACK WHITE
VIOLET VIOLET
RED RED
DISPENSER
