Electrical System; Energized Parts Charts; Self-Contained Water-Cooled Models - Manitowoc Marine Q 1800 Service Manual

Energized Parts Charts

SELF-CONTAINED WATER-COOLED MODELS

Ice Making
Sequence
Of
Operation
Start-Up
1
1. Water Purge
2. Refrigeration System
Start-Up
Freeze Sequence
3. Pre-Chill
Freeze
Harvest Sequence
5. Water Purge
6. Harvest
Automatic
7.
Shut-Off
1
Initial Start-Up or Start-Up After Automatic Shut-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:

Electrical System

Control Board Relays
1 2 3
Water Water Fill Hot Gas
Pump Valve Valve(s)
On Off On
Off On On
May cycle
Off Off
On/Off
during first
45 sec.
On Off
-------------
Cycles On,
then Off 1
more time
30 sec.
On Off, 15 On
sec. On
Off Off On
Off Off Off
Electrical System
4 5
Water
Contactor
Dump
Coil
Valve
On Off
Off On
Off On
Off On
On On
Off On
Off Off
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
(step7). If the bin switch is closed, the ice machine
will go to the freeze sequence (steps 3-4).
5A Length
Of
Compressor
Time
Off 45 Seconds
On 5 Seconds
On 30 Seconds
Until 7 sec.
On water contact
with ice
thickness
probe
Factory-set at
On
45 Seconds
Bin switch
On
activation
Until bin switch
Off
re-closes
1