Manitowoc CVD0675, Руководство техника, Страница: 86 / 204

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Harvest Sequence
4. Water Purge
The water pump continues to run, and the water dump
valve energizes for 45 seconds to purge the water in
the sump trough. After the 45-second water purge, the
water pump and dump valve de-energizes.
Both cool vapor solenoid valves also open at the
beginning of the water purge to divert refrigerant gas
into the evaporator.
5. Harvest
The cool vapor solenoid valves remain open, and the
refrigerant gas warms each evaporator causing the
cubes to slide as a sheet, off the evaporator and into
the storage bin. The ice may fall first from either the
right or the left evaporator, or both at the same time.
The sliding sheet of cubes swings the water curtain
out, opening the corresponding bin switch.
The momentary opening and closing of the bin switch
de-energizes relay #2 (right) or #3 (left). Opening relay
#2 or #3 de-energizes the corresponding cool vapor
solenoid valve for the remainder of the Harvest sequence.
The momentary opening and reclosing of both bin
switches terminates the Harvest sequence and returns
the ice machine to the Freeze sequence (steps 2-3).
Automatic Shut-Off
6. Automatic Shut-Off
Ice Machine Section: When the storage bin is full at the
end of a Harvest sequence, the sheet of cubes fails to
clear either one or both of the water curtains. After one
or both water curtains are held open for 7 seconds, all
five relays open and the ice machine shuts off.
CVD ® Condensing Unit: When the refrigerant pressure
is low enough to open the low pressure switch, the
contactor coil is de-energized and the compressor and
condenser fan motor (CVD1475 only) stop.
The ice machine remains off until enough ice has been
removed from the storage bin to allow the ice to fall
clear of the water curtain(s). As the water curtain
swings back to the operating position, the bin switch
recloses and the ice machine restarts (steps 1-2).