The
ASU
processor monitors the supply voltage. When the voltage rises above 13.2
(26.4) volts it will start the compressor and after a short delay gradually increase the
speed of the compressor and cooling fan. The indicator LED will shift from yellow to
red. This operating condition is maintained until the holding plate is completely frozen
at approximately -14°C (7°F). This can take between 45 minutes and 2 hours depend-
ing on the model, ambient temperature and box size.
As long as the
ASU
processor senses surplus power the holding plate is maintained in
the frozen condition. If the holding plate temperature rises to -10°C (14°F), the com-
pressor re-starts and the red LED comes on again.
When the supply voltage falls below 12.7 (25.4) volt, the refrigeration energy stored in
the holding plate will maintain the box temperature for many hours (up to 12 hours de-
pending on the box size, ambient temperature and insulation).
When all the thermal energy stored in the holding plate is used and the plate tempera-
ture rises to -1°C (30°F) the ASU system will start the compressor at a low speed to
bring the plate temperature down 6°C (21°F). This will maintain a very stable box tem-
perature using the minimum amount of battery power.
“MAN.TEMP” position:
This position can be used when shore-power is connected and energy saving is not re-
quired or whenever a higher or lower refrigerator temperature is desired. The ASU
program is stopped and the temperature is regulated by means of the temperature
knob on the control panel. Turn the control clockwise for a colder temperature setting.
The “A” (Accumulation) position approximates the freezing point of the holding plate.
In the ”MAN.TEMP” position, the compressor runs at a low speed to maintain the set
temperature. If the difference between the set and actual temperature is greater than
6°C, the compressor will automatically speed up for faster cooling. As soon as the
temperature comes down the compressor speed will be reduced for the lowest power
consumption and quietest operation.
9.2.3 INDICATOR LIGHTS
Green:
Power and system on, compressor not running. Set temperature reached.
Green + Yellow
: Compressor running at low speed in Normal Auto mode.
Green + Red
: Compressor running at high speed in the Normal/Auto mode.
Green + Red:
Compressor running in MAN.TEMP mode.
Flashing Yellow and/or Red:
Error signal. See Troubleshooting Guide.
Automatic Defrosting will take place automatically every tenth day of operation.
