Technical information

12/01/02

The sensor has two LED lamps that light to show that

power is supplied. Since the voltage is DC, the sensor is

polarity sensitive. The sensor has four wires. The orange

wire is capped off and not used. The black wire connects

to the coil of relay X7. The brown wire is the positive lead

and connects to terminal J2-1 on the power supply. The

blue wire is the negative lead and connects to terminal J2-

2. If these wires are crossed, the sensor will not shut the

unit down. The result will be that the spout will fill with ice

causing higher gear motor current and the gear motor pro-

tect fuse will blow. In this case, the bin control is the first

component to check.

The sensor has two adjustments that are factory set. The

first adjustment sets the operation mode of the sensor. It

must be in the D position. The second adjust the operating

distance of the infrared beam at approximately 4”. It should

be set so that the white dot on the dial is at 12 o’clock (top

dead center). These settings should not be altered.

5. KM CONTROL TRANSFORMER: The KM control trans-

former supplies 10.5 VAC to the control board through the

K2 connector. This 115V/10.5V stepdown transformer is a

heavy duty component with an internal thermal overload.

The primary winding of this transformer will handle higher

voltage without damage because the thermal overload will

open to protect the winding in the case of improper supply

voltage. The control board monitors the output voltage of

this control transformer and provides automatic reset high

and low voltage protection.

The red LED on the control board will not light if no control

voltage is supplied. The 115V transformer primary circuit is

supplied through the thermostatic bin control, control switch,

high pressure switch, and low pressure switch if included.

If either of these switches are open, there is not control

voltage at the K2 connector and the unit will not operate.

The transformer secondary circuit includes the cleaning

valve interlock switch. If this switch is open, no control

voltage is supplied to the K2 connector so the unit will not

operate. Always check the cleaning valve position and

interlock switch if the red LED is off.

Because of the voltage protection, if the control trans-

former fails, it is important to use the correct OEM part.

12/20/03

2/20/03