Digital Outputs; Fig. 62 - I/O Board Relay Contact Architecture - York YLAA0285SE Manual

SECTION 9 – SERVICE AND TROUBLESHOOTING
The suction transducers have a range from 0 to 400 PSIG
(27.5 barg). The output will be linear from 0.5VDC
to 4.5VDC over the 400 PSIG (27.5 barg) range. The
following is a formula that can be used to verify the
voltage output of the transducer. All voltage reading are
in reference to ground (unit case).
V = (Pressure in PSIG x .02) + .5
V = (Pressure in barg x .29) + .5
where V = dc voltage input to microprocessor board
Pressure = pressure sensed by transducer
The f ollowing are the I/O board connections for the
Suction Transducer:
System 1 Suction Transducer
J7-5 = +5VDC regulated supply to transducer.
J7-10 = VDC input signal to the microboard.
See the formula above for voltage readings that cor-
respond to specific suction pressures.
J7-9 = +5VDC return
J7-1 = drain (shield connection = 0VDC)
System 2 Suction Transducer
J9-5 = +5VDC regulated supply to transducer.
J9-10 = VDC input signal to the microboard.
See the formula above for voltage readings that cor-
respond to specific suction pressures.
J7-9 = +5VDC return
J7-11 = drain (shield connection = 0VDC)
184
or

Digital Outputs

Refer to the unit wiring diagram and Fig. 62. The digital
outputs are located on TB7, TB8, and TB9 and TB-10 of
the microboard. ALL OUTPUTS ARE 120VAC with the
exception of TB8-6 to TB8-7 which are the contacts that
can be used for a remote evaporator 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 120VAC to the respective output connection
energizing contactors, evaporator heater, and solenoids
according to the operating sequence (see Fig. 62).
120VAC is supplied to the I/O board via connections
at TB7-1, TB7-6, TB10-1, TB10-6, TB8-1 and TB9-1.
Fig. 62 illustrates the relay contact architecture on the
microboard.
TB7
TB7
TB10
TB10
TB8
FIG. 62 – I/O BOARD RELAY CONTACT
ARCHITECTURE
FORM 150.72-NM3 (1020)
ISSUE DATE 10/05/2020
SYS 1
TB7-2
COMP 1
TB7-3 LLSV 1
SYS 1
TB7-4
COMP 2
SYS 1
TB7-5
COMP 3
SYS 1
TB7-7
HGSV
SYS 1
TB7-8
FAN 2
SYS 1
TB7-9
FAN 1
SYS 1
TB7-10
FAN 3
SYS 2
TB10-2
COMPR 1 (4)
TB10-3 LLSV 2
SYS 2
TB10-4
COMPR 2 (5)
SYS 2
TB10-5
COMPR 3 (6)
SYS 2
TB10-7
HGSV
TB10-8
SYS 2
TB10-9
FAN 2
SYS 2
TB10-10
FAN 4
TB8-6
EVAP
PUMP
TB8-7
HEAT EXCH
TB8-2
HEATER
LD12722
JOHNSON CONTROLS