York Sun Select YV28, Manual

Page: 100 / 110

Table 92: Smart Equipment™ UCB - LEDs
Location Label Description Function and comments
POWER Green UCB power indicator Lit indicates 24 VAC is present at C and 24 V 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)
N
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
Table 93: Smart Equipment™ UCB - optional communication sub-board
Location Label Description Function and comments
FC+ FC (“Field Connected”) BUS BACnet MSTP communication
Positive of the VDC (typically, a fluctuating 1.5 to 3.5 V reading to COM; at least 0.25
V 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 V reading to COM; at least 0.25
V 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
O
Terminal FC BUS
connections
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”
EOL Green End Of Line indicator Lit indicates the EOL switch is selected ON
P
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
Installation Manual: YORK
®
Sun™ Select YV28 to YV50
100
Johnson Controls Ducted Systems