TCS UbiquiSTAT, Product Manual

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3.5 DIGITAL OUTPUTS (DO)
The various control outputs required by heat and cool stage control are mapped to physical terminal blocks on the
controller via mechanical relays. The mapping depends on the mode of operation for the controller, and can even change
dynamically during normal operation in heat pump mode. The relays’ terminals are described by the color of wire that is
traditionally used for that control wire:
Figure 2
Terminal
Designator
Color Function
R Red 24V HVAC Unit Power
W White Heat
Y Yellow Cool
G Green Fan
B/O Blue/Orange Reversing Valve
TC n/a Time Clock
Mapping is done as shown in the table below, based on system type (conventional or heat pump), and mode of operation.
If the 4th stage of heat or cool is desired in conventional mode, then the 3rd stage must also be enabled. Both
of these stages are optional and must be configured using the internal BACnet Explorer.
Figure 3
Terminals (Relays) Conventional
Heat Pump
(Normal)
Heat Pump
(Low Limit
Changeover)
Heat Pump
(Emergency
Heat)
W1 Heat 1 Heat 3 Heat 1 Heat 1
W2 * Heat 2 Heat 4 Heat 2 Heat 2
Y1 Cool 1 Heat 1/Cool 1 Cool 1
Y2 * Cool 2 Heat 2/Cool 2 Cool 2
G Fan Fan Fan Fan
B/O Heat/Cool 3, 4 * Reversing Valve Reversing Valve Reversing Valve
TC Heat/Cool 3, 4 *
*
Time Clock (TC) : When used as a time clock output, this relay opens or closes based on the occupancy state. This relay
is isolated from other heating and cooling relays, which share a common connection with the R terminal. If this output is
used as a heating or cooling stage, the R terminal must be jumpered to one of the TC terminals. This is an open or close
relay that will support 24V.
Reversing Valve (B/O) : When the UbiquiSTAT
™
is in heat pump mode, the B/O terminal is used as a reversing valve
output. It may be configured as open or closed for cooling (the default is closed) via the polarity property. If the
UbiquiSTAT is configured as conventional, it may be used as an additional heating or cooling stage.
INITIAL
SETUP