Manitowoc Marine Q 1000, Руководство по обслуживанию

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16
Electrical System
There are other problems that may cause
compressor start-up failure with a good PTCR in a
new, properly wired ice machine.
Room
Manitowoc
Part Number
Cera-Mite
Model Temperature
Resistance
Part Number
Q1800 8504913 305C9 8-22 Ohms
•
The voltage at the compressor during start-up is
too low.
Manitowoc ice machines are rated at
±
10% of
nameplate voltage at compressor start-up. (Ex:
An ice machine rated at 208-230 should have a
compressor start-up voltage between 187 and
253 volts.)
MEASURE OHMS BETWEEN
CENTER TAB AND END TAB
•
The compressor discharge and suction pressures
are not matched closely enough or equalized.
These two pressures must be somewhat
equalized before attempting to start the
compressor. The hot gas valve (and HPR valve
on remotes) energizes for 45 seconds before the
compressor starts, and remains on 5 seconds
after the compressor starts. Make sure this is
occurring before assuming that the PTCR is
bad.
CHECKING THE PTCR
WARNING
Disconnect electrical power to the entire ice
machine at the building electrical disconnect box
before proceeding.
1. Visually inspect the PTCR. Check for signs of
physical damage.
NOTE: The PTCR case temperature may reach
210
°
F (100
°
C) while the compressor is running.
This is normal. Do not change a PTCR just because
it is hot.
2. Wait at least 10 minutes for the PTCR to cool to
room temperature.
3. Remove the PTCR from the ice machine.
4. Measure the resistance of the PTCR as shown
below. If the resistance falls outside of the
acceptable range, replace it.
LEAVE JUMPER
WIRE IN PLACE
SV1541
Manitowoc PTCR 8504913