5703827-XIM-A-0319
Johnson Controls Ducted Systems
41
J
LPS2
(right pin)
24 VAC hot out for refrigerant circuit 2 Low
Pressure Switch
Not effective for one stage compressor UCBs. Connects through
circuit trace to the left HSP2 pin
LPS2
(left pin)
24 VAC hot return from refrigerant circuit 2 Low
Pressure Switch
Not effective for one stage compressor UCBs. Input is only
considered after 30 seconds of C2 output; afterwards, input must be
present to allow C2 output. Three LPS2 trips in a one hour period
cause a “Low Pressure Switch 2 Lockout” and C2 output is then
prevented until alarm reset.
FAN OVR
(right pin)
24 VAC hot out for indoor blower FAN Overload
relay contact/motor protector switch
Connects through circuit trace to the R terminal
FAN OVR
(left pin)
24 VAC hot return from indoor blower FAN
Overload relay contact/motor protector switch
Input is only considered if FAN output is needed; input must be
present to allow FAN output and unit operation. One FAN OVR trip
lasting longer than 5 minutes or three FAN OVR trips in a two hour
period cause a “Fan Overload Lockout” and unit operation is then
prevented until alarm reset.
Smart Equipment™ UCB - SA BUS
1
connections
1.
When wiring unit and other devices using the SA Bus and FC Bus, see Table 28.
Location
Label
Description
Function and comments
K
PWR
Power for SA (“Sensor-Actuator”) BUS devices
Also incorporated in the J8 6-pin phone jack connector at the left-center of
the board. Positive of the 15 VDC (reading to C) circuit for powering an
optional netstat and/or Multi Touch gateway
C
Common for SA BUS power and communication
circuits
Also incorporated in the J8 6-pin phone jack connector at the left-center of
the board. Negative of the SA BUS circuits
–
Communication for SA BUS devices
Also incorporated in the J8 6-pin phone jack connector at the left-center of
the board. Positive of the VDC (typically, a fluctuating 1.5 to 3.5 volts
reading to C; at least 0.25 volts lower than +) SA BUS communication
circuit to optional economizer board, 4-stage board, fault detection &
diagnostics board, netstat and/or Multi Touch gateway
+
Communication for SA BUS devices
Also incorporated in the J8 6-pin phone jack connector at the left-center of
the board. Positive of the VDC (typically, a fluctuating 1.5 to 3.5 volts
reading to C; at least 0.25 volts higher than
–
) SA BUS communication
circuit to optional economizer board, 4-stage board, fault detection &
diagnostics board, netstat and/or Multi Touch gateway
L
J8
6-pin phone jack connector
Incorporates the SA BUS terminals for convenience/alternate connection
of SA BUS devices, primarily used for temporary service connection of the
Multi Touch gateway
Smart Equipment™ UCB - user interface
Location
Label
Description
Function and comments
M
Display
On-board, 2-line x 8-character back-lit display
On-board display, buttons and joystick allow access to UCB,
economizer, 4-stage and FDD board parameters
ENTER
Button for display menu acknowledgment and navigation
CANCEL
Button for display menu navigation and zeroing of active
compressor ASCD timer
JOY
4-way Joystick for display menu navigation
Smart Equipment™ UCB - refrigerant circuit safety switch and indoor blower overload connections (Continued)
Location
Label
Description
Function and comments
