Sub-Zero 700-3 BASE, Technical & Service Manual

Page: 28 / 114

Electronic Control System
Integrated
(700-
3
BASE)
Series
3-16
#3758424 - Revision B - December, 2005
Monitor Compressor Run Duration, Displays If Service is Needed
The microprocessor observes the state of the compressor relay to determine the length of compressor run time (See
Figure 3-22). If the compressor runs 100% (Freezer = 6 hours, Refrigerator = 4 hours), an error code is logged (EC
40), and defrost will be initiated, but SERVICE will not flash.
If several 100% compressor run periods occur, and a drawer was not opened during the last excessive compressor
run period, and the temperature in the zone is not able to fall half way between the set point and the low off-set,
then SERVICE will flash (See Figure 3-23).
NOTE: To clear a flashing SERVICE and error codes, the problem must be corrected, then the Alarm ON/OFF key
pressed for 15 seconds. Failure to clear an error code will cause SERVICE to display constant.
NOTE: If the unit is ever switched OFF then back ON, the compressor will not energize for at least 3 minutes. This
3 minute minimum OFF time is used to protect the compressor and its electricals.
Figure 3-23. Service Flashing if several 100% compressor run periods occurred, a drawer was not opened
during last excessive run period, and temperature is not able to fall half way between set point & low off-set.
UNIT ICE
REFRIGERATOR
ON/OFF
ON/OFF
ON/OFF
WARMER COLDER
FREEZER
WARMER COLDER
SERVICE
Figure 3-22. 700BCI-3 Signal Trace Schematic - Compressor Run
RED
PURPLE
60 CYCLES
BLACK
L1
NEUTRAL
WHITE
STARTING
FRZ FAN MOTOR
TERMINATOR
CONDENSER FAN
RELAY
PROTECTOR
OVERLOAD
COMPRESSOR
COMPRESSOR
CAPACITOR
RUNNING
WHITE
HIGH VOLTAGE SCHEMATIC
115 VOLTS
MAIN BOARD
PIN 1
PIN 1
PIN 1
PIN 1
PIN 1
WHITE
BLUE
(WHEN
USED)
J5
J3
J4
J6
P2
J2
P1
P3
P4
M
M
M
M
1. Compressor relay closed,
allowing 115 Volts AC to
compressor. This is
observe by microprocessor.