FORM 201.26-NM1
ISSUE DATE: 1/19/2018
SECTION 9 – SERVICE AND TROUBLESHOOTING
JOHNSON CONTROLS
162
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. Following is a formula that can be used to verify
the voltage output of the transducer. All voltage read-
ing are in reference to ground (unit case).
V = (Pressure in PSIG x .02) + .5
or
V = (Pressure in barg x .29) + .5
where V = DC voltage input to microprocessor
Pressure = pressure sensed by transducer
Following 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).
Digital Outputs
Refer to the unit wiring diagram and Figure 39 on page
. 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 Figure 39 on
120VAC is supplied to the I/O board via connections
at TB7-1, TB7-6, TB10-1, TB10-6, TB8-1 and TB9-1.
illustrates the relay contact
architecture on the microboard.
FIGURE 39 -
I/O BOARD RELAY CONTACT
ARCHITECTURE
LD12722A
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
TB10-8
TB10-9
TB10-10
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
TB7-7
TB7-9
TB7-10
TB7-8
TB8-2
HEAT EXCH
HEATER
Summary of Contents for YCWL0056SE
Page 4: ...FORM 201 26 NM1 ISSUE DATE 1 19 2018 JOHNSON CONTROLS 4 THIS PAGE INTENTIONALLY LEFT BLANK...
Page 30: ...FORM 201 26 NM1 ISSUE DATE 1 19 2018 JOHNSON CONTROLS 30 THIS PAGE INTENTIONALLY LEFT BLANK...
Page 146: ...FORM 201 26 NM1 ISSUE DATE 1 19 2018 JOHNSON CONTROLS 146 THIS PAGE INTENTIONALLY LEFT BLANK...
Page 154: ...FORM 201 26 NM1 ISSUE DATE 1 19 2018 JOHNSON CONTROLS 154 THIS PAGE INTENTIONALLY LEFT BLANK...
Page 168: ...FORM 201 26 NM1 ISSUE DATE 1 19 2018 JOHNSON CONTROLS 168 THIS PAGE INTENTIONALLY LEFT BLANK...
Page 186: ...FORM 201 26 NM1 ISSUE DATE 1 19 2018 JOHNSON CONTROLS 186 NOTES...