21
B. Sequence of Operation
1. Sequence Cycles and Shutdown
a) KM-1601SAH/3 "G" Control Board
IMPORTANT
KM-1601SAH/3 utilize a "G" control board and TBC. For KM-1601SAH/3
operation, the K4 jumper (4A4883G01) must be in place on the control board
RED K4 connector or the unit will not operate.
The steps in the sequence are as outlined below. When power is supplied, CB red
"POWER OK" LED and green "BC CLOSED" LED turn on. If red "POWER OK" LED is
off, clear ice away from TBC bulb in the storage bin area. If yellow "BC OPEN" LED is
on, the unit will not start. In this case check that CB has the K4 jumper in place on CB
RED K4 connector. There is a 5-second delay before startup. Note that the order of the
component LEDs from the outer edge of CB is 1, 4, 3, 2.
(1) 1-Minute Fill Cycle
LED 4 is on. WV and X11 relay energize and the 1-minute ll cycle begins. After
1minute, CB checks for a closed F/S. If F/S is closed, the harvest cycle begins. If open,
WV remains energized through additional 1-minute ll cycles until water lls the water
tank and closes F/S. This serves as a low water safety to protect PM.
(2) Initial Harvest Cycle
LEDs 1, 4, and 2 are on. WV and X11 relay remain energized, Comp, FM, HGV, and
X10 relay energize. CB monitors the warming of the evaporator via the thermistor located
on the suction line. When the thermistor reaches 48°F (9°C), CB reads a 3.9 kΩ signal
from the thermistor and turns harvest termination over to the harvest timer (S4 dip switch
1 & 2). The harvest timer has settings of 60, 90, 120, and 180 seconds. For details, see
"II.C.3.b) Harvest Timer (S4 dip switch 1 & 2)." WV is energized during harvest for a
maximum of 6 minutes or the length of harvest minus 0 or 50 seconds (harvest pump
timer (S4 dip switch 7)), whichever is shorter. CAUTION! Do not adjust S4 dip switch
7 out of the factory default position on this model. Adjustment outside of the
factory default position may result in damage to the icemaker. LED4 turns off when
WV and X11 relay de-energize. LED 3 turns on and PM energizes and runs for the last
0 or 50 seconds of harvest depending on S4 dip switch 7 setting. This circulates water
over the evaporator for the last 0 or 50 seconds of harvest. PM is energized through
CB K1 ten-pin connector pin #5 (DBU wire) and the X10 relay. When the harvest timer
terminates, the harvest cycle is complete. CB checks the position of F/S and proceeds
to the freeze cycle if it is closed or calls for a 1-minute ll cycle if it is open. The minimum
total time allowed by CB for a complete harvest cycle is 2 minutes.
(3) Freeze Cycle
LED 1 is on. Comp and FM remain energized, PM energizes or remains energized
depending on harvest pump timer (S4 dip switch 7) setting. LLV energizes. HGV and
X10 relay de-energize. The unit is held in freeze by a 5-minute short cycle protection
timer (CB will not accept a signal from F/S during the rst 5 minutes of freeze). After the
5-minute short cycle protection timer terminates, CB turns freeze termination over to F/S.
As ice builds on the evaporator, the water level in the water tank lowers. The freeze cycle