Manitowoc P Series, Installation, Use And Care, And Service Manual

Page: 40 / 62

6-1
Section 6 Service
Section 6
Electrical System
P MODEL POINT OF USE
Ice Making Sequence of operation Chart
Control Board Relays Contactor
SEQUENCE
1 2 3 4 5 3A
of
OPERATION
WATER
PUMP
WATER
FILL
VALVE
CONTACTOR
COIL
WATER
DUMP
VALVE
SUCTION LINE
SOLENOID
EVAPORATOR
HEATERS
LENGTH
of
TIME
INITIAL START-UP/
START UP AFTER
AUTO SHUT-OFF:
1. Water Purge
on off off on off off
45
Seconds
FREEZE
SEQUENCE:
2. Prechill
off
May
cycle
on/off
for first
off off on off 30
Seconds
45
seconds
3. Freeze
on
Cycle on
then off
1 more
time
off off on off
Until
10 second
water contact
with ice
thickness
probe
HARVEST
SEQUENCE:
4. Water Purge
on
30 sec.
off on on off on
Water purge
factory set at
45
15 sec.
on
Seconds
5. Harvest
off off on off off on
Bin switch
activation
6.
AUTO SHUT-OFF
off off off off off off
Until
bin switch
re-closes
Control Board Safety Timers
Freeze Sequence:
•
The ice machine is locked in the freeze
sequence for the first 6 minutes, not allowing the ice
thickness probe to initiate a harvest sequence.
•
The maximum freeze time is 60 minutes, at
which time the control board automatically initiates
a harvest sequence (steps 4-5).
•
The maximum "on time" for the water fill valve
is 6 minutes, at which time it automatically turns
off.
Harvest Sequence:
•
The maximum "on time" for evaporator heaters
is 5.5 minutes, at which time the contactor will
automatically de-energize to shut the heaters
off.
•
The maximum harvest time is 6-1/2 minutes, at
which time the control board automatically
terminates the harvest sequence. If the bin
switch is open, the ice machine will go to
Automatic shut-off (step 6). If the bin switch is
closed, the ice machine will go to the freeze
sequence (steps 2-3).