Quantech QCC2015CEE, Installation, Operation And Maintenance Manual, Page: 148 / 172

QUANTECH
148
Form QCC2-NM1
Issue Date: 5/20/2021
SECTION 9 – SERVICE AND TROUBLESHOOTING
Digital outputs
Refer to the unit wiring diagram and Figure 42 on page
148 . The digital outputs are located on TB7, TB8, and
TB9 and TB-10 of the microboard. All outputs are
120 VAC with the exception of TB8-6 to TB8-7 which
are the contacts that can be used for a remote evapora-
tor pump start signal. The voltage applied to either of
these terminals would be determined by field wiring.
Each output is controlled by the microprocessor by
switching 120 VAC to the respective output connection
energizing contactors, evaporator heater, and solenoids
according to the operating sequence (see Figure 42 on
page 148
).
120 VAC is supplied to the I/O board via connections
at TB7-1, TB7-6, TB10-1, TB10-6, TB8-1 and TB9-1.
Figure 42 illustrates the relay contact architecture on
the microboard.
Figure 42 - I/O Board Relay Contact Architecture
LD12722
SYS 1
COMP 1
TB7-2
SYS 1
COMP 2
TB7-4
SYS 1
COMP 3
TB7-5
TB7-3 LLSV 1
TB8-6
EVAP
PUMP
TB8-7
TB7
SYS 2
HGSV
TB10-7
SYS 2
FAN 2
TB10-8
TB10-9
TB10-10 SYS 2
FAN 4
TB10
TB8
TB10
SYS 2
COMPR 1 (4)
TB10-2
LLSV 2
TB10-3
SYS 2
COMPR 2 (5)
TB10-4
SYS 2
COMPR 3 (6)
TB10-5
TB7
SYS 1
HGSV
TB7-7
SYS 1
FAN 1
TB7-9
SYS 1
FAN 3
TB7-10
TB7-8
SYS 1
FAN 2
TB8-2
HEAT EXCH
HEATER
*
*
* Not Used