Manitowoc Marine Q 1800 Service Manual page 23

General
Q-Model control boards use a dual voltage
transformer. This means only one control board is
needed for both 115V and 208-230V use.
Safety Limits
In addition to standard safety controls, such as the
high pressure cut-out, the control board has built-
in safety limits.
These safety limits protect the ice machine from
major component failures. For more information,
see "Safety Limits".
Electrical System
Inputs
The control board, along with inputs, controls all
electrical components, including the ice machine
sequence of operation. Prior to diagnosing, you
must understand how the inputs affect the control
board operation.
Refer to specific component specifications
(inputs), wiring diagrams and ice machine
sequence of operation sections for details.
As an example, refer to "Ice Thickness Probe" in
the component specifications section of this
manual for information relating to how the probe
and control board function together.
This section will include items such as:
• How a harvest cycle is initiated
• How the harvest light functions with the probe
• Freeze time lock-in feature
• Maximum freeze time
• Diagnosing ice thickness control circuitry
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