Manitowoc QD0202A, Руководство по обслуживанию

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Part No. 80-1100-3
6-1
Section 6
Electrical System
Energized Parts Charts
SELF-CONTAINED AIR- AND WATER-COOLED MODELS
1. Initial Start-Up or Start-Up After Automatic Shut-Off
Condenser Fan Motor
The fan motor is wired through a fan cycle pressure
control, therefore, it may cycle on and off.
Harvest Water Purge
The circuit board has an adjustable water purge in the
harvest cycle. This permits a 15, 30 or 45 second purge
cycle.
Auto Shut-Off
The ice machine remains off for 3 minutes before it can
automatically restart. The ice machine restarts (steps 1-
2) immediately after the delay period, if the bin switch re-
closes prior to 3 minutes.
Safety Timers
The control board has the following non-adjustable
safety timers:
FREEZE SEQUENCE
• The ice machine is locked into the freeze cycle 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 5-6).
HARVEST SEQUENCE
The maximum harvest time is 3-1/2 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 7). If the bin
switch is closed, the ice machine will go to the freeze
sequence (steps 3-4).
Ice Making
Sequence Of
Operation
Control Board Relays Contactor
Length
Of Time
1 2 3 4 5 5A 5B
Water
Pump Water Fill
Valve
Harvest
Valve(s)
Water
Dump
Valve
Contactor
Coil
Com-
pressor
Condenser
Fan Motor
START-UP
1
1. Water Purge
On Off On On Off Off Off 45 Seconds
2. Refrigeration
System
Start-Up
Off On On Off On On
May Cycle
On/Off
5 Seconds
FREEZE
SEQUENCE
3. Pre-Chill
Off
May cycle On/
Off during first
45 sec.
-----------
Cycles On,
then Off 1
more time
Locked Out
After Six
Minutes
Off Off On On
May Cycle
On/Off
30 Seconds
4. Freeze On Off Off On On
May Cycle
On/Off
Until 7 sec.
water contact
with ice
thickness probe
HARVEST
SEQUENCE
5. Water Purge
On
30 sec. Off,
15 sec. On
On On On On
May Cycle
On/Off
Factory-set at
45 Seconds
6. Harvest Off Off On Off On On
May Cycle
On/Off
Bin switch
activation
7. AUTOMATIC
SHUT-OFF
Off Off Off Off Off Off Off
Until bin switch
re-closes