Dc Voltage Requirements And Polarity; R Equirements /C Omponents; Power Board Dc Fuse; Dc Power Wiring Requirements - Norcold 1200 Series Service Manual

ELECTRICAL REQUIREMENTS AND COMPONENTS

DC Voltage Requirements and Polarity

The operating controls require 10.5 to 15.4 Vdc to
operate. The positive wire lead (+) connects to power
board terminal 12VDC; the negative wire lead (–)
connects to terminal GND1.

Power Board DC Fuse

Never replace a fuse with a higher amperage
rated fuse. Always use the specified fuse.
The controls circuit fuse is a standard automotive blade
type fuse. It is located on the power board, terminal F1.

DC Power Wiring Requirements

Never use undersized wires to supply DC
power to the power board. Undersized wires
may cause wires to overheat and creates an
electrical fire hazard.
18 AWG is the minimum AWG size wire that can be
used for connecting DC power to 2-way models. The
fuse size for overload protection must not exceed 6
amps.

AC/DC Converter as Power Source

The power board must be supplied 12 volt DC only from
the filtered output (battery side) of a converter.
Unfiltered voltage (commonly referred to as AC ripple)
output of AC/DC converters can cause the electronic
controls to set false fault codes. It can also turn off the
refrigerator or prevent the refrigerator from turning off.
Refrigerator Service Manual
WARNING
WARNING

Lamp/Thermistor Assembly

The operation of the fresh food compartment 12 volt
DC lamp is controlled by two switches mounted on
the underside of the divider section of the refrigerator.
Opening either fresh food comparment door allows the
switch to close, which turns on the light.
Leaving the door ajar or open for more than two minutes
causes the controls to display a "dr" fault code. Closing
the door turns off the light and clears the "dr" fault from
the display. The fault code is stored in the diagnostic
mode non-volatile memory. For "dr" troubleshooting
procedures, see page 15. As shown in Figure 27, the
light assembly harness and thermistor share a molded
connector.
Older models, S/N 83170 and lower. the ther mistor is
attached to the 20th fin, counting from right to left from
the label side of the cabinet.
On models S/N 832171 and higher or older models
equipped with a frost management poer board the
thermistor is connected to the second fin, counting
from right to left from the label side of the cabinet. The
thermistor is the temperature sensing circuit sensor. If it
fails open or shorted, the controls activate the Backup
Operation Mode to keep the refrigerator in operation.
Connector
Clip Thermistor
Figure 27. Lamp/thermistor assembly

Divider Heater

The divider heater is permanently "foamed" between
the divider separating the freezer and fresh food
compartment. The controls constantly monitor power
board voltage output to the heater through built in
diagnostics (see pages 46 and 50). Turning the
refrigerator on automatically send power to the heater.
Light bracket
Lightbulb
Light cover
1200XX/120X-IMXX Models
29