Service manual

Section 6 Electrical System
Part No. 80-1206-3 6-13
Component Specifications and Diagnostics
CONTROL BOARD
All QuietQube® control boards incorporate the following
features. Refer to “Sequence of Operation” for additional
information specific to your model.
Harvest/Safety Limit Light
This light’s primary function is to be on as water contacts
the ice thickness probe during the freeze cycle, and
remain on throughout the entire harvest cycle. The light
will flicker as water splashes on the probes. The light’s
secondary function is to continuously flash when the ice
machine is shut off on a safety limit, and to indicate
which safety limit shut off the ice machine.
Freeze Time Lock-In Feature
The ice machine control system incorporates freeze time
lock-in feature. This prevents the ice machine from short
cycling in and out of harvest. The control board locks the
ice machine in the freeze cycle for six minutes. If the
water contacts the ice thickness probe during these six
minutes, the harvest light will come on (to indicate that
water is in contact with the probe), but the ice machine
will stay in the freeze cycle. After the six minutes are up,
a harvest cycle is initiated.
To allow the service technician to initiate a harvest cycle
without delay, this feature is not used on the first cycle
after moving the toggle switch OFF and back to ICE.
Maximum Freeze Time
The control system includes a built-in safety that will
automatically cycle the ice machine into harvest after 60
minutes in the freeze cycle.
Safety Limits
There are two safety limits that protect the ice machine if
the freeze or harvest cycles are outside of their
guidelines.
Three-Minute Delay
Q0600C/IB0600C/Q0800C/IB0800C/
Q1000C/IB1000C/SU1000C/QDUALC
The three-minute delay is initiated whenever the ice
machine cycles off (automatic shut-off) on a full bin.
The delay period starts when a water curtain is open for
7 continuous seconds in the harvest cycle.
• If the 3-minute delay period has expired, closure of
the water curtain will initiate an immediate start-up of
a freeze sequence.
• If the water curtain closes before the 3-minute delay
period has expired, the ice machine will start a freeze
sequence immediately after the 3-minute delay
period expires.
• The 3-minute delay period is over-ridden when the
toggle switch is moved to the OFF position, then
back to ICE.
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 specification
section of this manual for information relating to how the
probe and control board functions together.
Control Board Relays
The control board relays energize and de-energize
system components.
Relays are not field replaceable.
QDUALC Water Assist Harvest
Typical duration of a harvest sequence is less than 2.5
minutes, when the harvest sequence time reaches 4
minutes the following occurs: 4 minutes into a Harvest
Sequence. The water fill valve will energize to fill the
trough with water. 5 minutes into a Harvest Sequence.
The water pump will energize and water will flow over
the evaporators. The water fill valve and water pump
remain on until all bin switches have been activated, or
until the 7 minute Harvest Sequence time limit is
reached.