Sub-Zero 700TC-3 Service Manual page 30

Electronic Control System
Monitor Compressor Run Duration, Displays If Service is Needed
In all models except the 700TF/I-3, the microprocessor observes the changing state of the compressor relays to
determine the length of compressor run time (See Figure 3-25). If a compressor runs 100% (Fre = 6 hours / Ref = 4
hours), an error code is logged (EC 40 / EC 50, respectively), and defrost is initiated, but SERVICE will not flash.
If several 100% run periods occur, and the compartment temperature does not fall to at least the set point / low off-
set temperature average (and the door is not opened during the last run period), then SERVICE will flash along with
the error code (See Figure 3-26).
NOTE: To clear a flashing SERVICE and EC, the problem must be corrected, then switch the unit off then back on
and/or press the Bell ON/OFF key for 15 seconds. Failure to clear an error code will cause SERVICE to display
constant once Diagnostic Mode is initiated.
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.
HIGH VOLTAGE
J5
J7
E2 E7 E10 E6
J3
J2 J1
Figure 3-25. 700TC/I-3 Signal Trace Schematic (High Voltage) of Compressor Electrical System
SERVICE
Figure 3-26. "SERVICE", "40" or "50" and "EC" Flashing = Several Excessive Compressor Run Periods
#3758412 - Revision B - December, 2006
115 VOLTS
L1 NEUT
60 CYCLES
BLACK
WHITE
GRAY
length of compressor
run time is monitored
by microprocessor.
J6
PURPLE
J4
Integrated
Integrated
(700-
(700-
WHITE
REFRIGERATOR
FAN SWITCH
M
REFRIGERATOR
OVERLOAD
PROTECTOR
FREEZER
OVERLOAD
PROTECTOR
M
FREEZER
FAN
SWITCHES
PURPLE
M
FREEZER
COLDER WARMER COLDER
3-16
3
3 Series
Series
T ALL)
T ALL)
REFRIGERATOR
RED FAN MOTOR
M
RUNNING
CAPACITOR
(WHEN USED)
REFRIGERATOR
STARTING
COMPRESSOR
RELAY
RUNNING
CAPACITOR
(WHEN USED)
FREEZER
STARTING
COMPRESSOR
RELAY
FREEZER
RED
FAN MOTOR
M
ICE
REFRIGERATOR
WARMER
ON/OFF
UNIT
ON/OFF
ON/OFF