5567611-BIM-B-1218
Johnson Controls Ducted Systems
75
Smart Equipment™ UCB - LEDs
Location
Label
Description
Function and comments
N
POWER
Green UCB power indicator
Lit indicates 24 VAC is present at C and 24V terminals
FAULT
Red hard lockout, networking error and firmware
error indicator
1/2 second on/off flashing indicates one or more alarm is currently active,
1/10th second on/off flashing indicates a networking error (polarity,
addressing, etc.) or a firmware error (likely correctable with re-loading
from USB flash drive)
SA BUS
Green UCB SA bus communication transmission
indicator
Lit/flickering indicates UCB SA bus communication is currently active, off
indicates the UCB is awaiting SA bus communication
Smart Equipment™ UCB - optional communication sub-board
Location
Label
Description
Function and comments
O
1
Terminal FC
BUS
connections
FC+
FC (“Field Connected”) BUS BACnet MSTP
communication
Positive of the VDC (typically, a fluctuating 1.5 to 3.5 volts reading to
COM; at least 0.25 volts higher than
–
) FC bus BACnet MSTP
communication circuit
FC–
FC (“Field Connected”) BUS BACnet MSTP
communication
Positive of the VDC (typically, a fluctuating 1.5 to 3.5 volts reading to
COM; at least 0.25 volts lower than +) FC bus BACnet MSTP
communication circuit
COM
Common for the FC (“Field Connected”) BUS
BACnet MSTP communication circuit
Negative of the VDC FC bus BACnet MSTP communication circuit
SHLD
Shield for the FC (“Field Connected”) BUS
BACnet MSTP communication circuit
Earth ground reference of the cable to prevent interference on the
FC bus BACnet MSTP communication circuit
Q
EOL
switch
End Of Line selector switch for the FC BUS
BACnet MSTP communication circuit
ON selected only for the UCB that is the terminus of the FC bus
BACnet MSTP communication cable to prevent signal “bounce-
back”
P
EOL
Green End Of Line indicator
Lit indicates the EOL switch is selected ON
FC BUS
Green FC bus communication transmission
indicator
Lit/flickering indicates outgoing UCB FC bus communication is
currently active, off indicates the UCB is awaiting incoming FC bus
communication
R
ISO PWR
Green communication board Isolated Power
indicator
Lit indicates the UCB is supplying power to the communication sub-
board
