Manitowoc QD0202A, Service Manual

Page: 62 / 175

Electrical System Section 6
6-6
Part No. 80-1100-3
4. FREEZE
The water pump starts after the 30-
second pre-chill. An even flow of
water is directed across the
evaporator and into each cube cell,
where it freezes.
After six minutes the water inlet valve
is locked out and can not add
additional water.
When sufficient ice has formed, the
water flow (not the ice) contacts the
ice thickness probes. After
approximately 7 seconds of continual
contact, a harvest cycle is initiated.
NOTE: The ice machine cannot
initiate a harvest cycle until a 6-
minute freeze lock has expired.
Figure 6-4.
Self-Contained — Freeze
Table 6-4. Self-Contained Models
4. Freeze (Until 7 Seconds of Water Contact with Ice Thickness Probe)
Toggle Switch ICE
Bin Switch Closed
Control Board Relays
#1 Water Pump Closed / ON
#2 Water Fill Valve Cycles ON then OFF
#3 Harvest Solenoid Open / OFF
#4 Water Dump Valve Open / OFF
#5 Contactor Coil Closed / ON
Compressor ON
Condenser Fan Motor ON
Safety Controls (Which could stop ice machine operation)
High Pressure Cut-Out Closed
Main Fuse (On Control Board) Closed
*OVERLOAD
FAN CYCLE CONTROL
BIN SWITCH
TB35
TB33
(52)
(51)
(48)
CONTACTOR
CONTACTS
L1
(42)
(66)
(64)
ICE THICKNESS PROBE
WATER LEVEL PROBE
NOT USED
TB35
HIGH PRES
CUTOUT
TB32
L1
(55)
RUN CAPACITOR
RUN CAPACITOR**
C
S R
TB34
(53)
(47)
(85) (86)
COMPRESSOR
FAN MOTOR
(AIR COOLED ONLY)
R R
(45)
(46) (50)
PTCR
BIN SWITCH LIGHT
HARVEST LIGHT/
SAFETY LIMIT CODE LIGHT
CLEAN LIGHT
WATER LEVEL
(49)
(63)
(62)
(66)
(65)
(69)
ICE
OFF
CLEAN
(67)
(68)
1F
1C
LOW D.C.
VOLTAGE
PLUG
(62)
1G
TOGGLE SWITCH
68
67
69
66
62
VIEW FOR WIRING
INTERNAL WORKING
VIEW
TB37
(74)
(59)
(73)
(56)
CONTACTOR
COIL
TERMINATES AT
PIN CONNECTION
TB30
TB30
TB30
TB30
L2 (N)
SEE SERIAL PLATE FOR VOLTAGE
(58)
FUSE (7A)
TRANS.
2
4
1
3
5
(61)
(60)
TB31
(76)
(98)
(57)
(99)
(75)
HARVEST
SOLENOID
DUMP
SOLENOID
(81)
WATER
PUMP
(77)
(80)
(21) (22)
WATER
VALVE
TB30
TB30
(20)
SV1646-4