Generic Building Automation; System Module; Input Devices And System; Functions - Trane IntelliPak 2 Series Installation, Operation And Maintenance Manual

Figure 5. Outside air tubing schematic
Fresh Air
Transducer
Upper
Low
Left side
Flow
High
Ring
Lo Hi
Upper
Low
Flow
High
Ring
Figure 6. Return air pressure tubing schematic
Fresh Air
Transducer
Left side
Lo
Outside Air
Return Plenum
Pressure
Generic Building Automation System
Module
(GBAS - Optional used with non-Trane building control
systems)
The Generic Building Automation System (GBAS)
module allows a non-Trane building control system to
communicate with the rooftop unit and accepts
external setpoints in the form of analog inputs for
cooling, heating, supply air pressure, and a binary
Input for demand limit. Refer to the "Field Installed
Control Wiring" section for the input wiring to the
GBAS module and the various desired setpoints with
the corresponding DC voltage inputs for VAV, SZVAV,
RR and CV applications.
Input Devices and System Functions
The descriptions of the following basic Input Devices
used within the UCM network are to acquaint the
operator with their function as they interface with the
various modules. Refer to the unit's electrical
schematic for the specific module connections.
RT-SVX24Q-EN
Upper
Low
Flow
High
Ring
NC
Upper
Low
NO
Flow
High
Ring
C
Hi
NC
NO
C
Fresh Air
Transducer
Left side
Lo Hi
NC
NO
C
Constant Volume (CV) and Variable Air
Volume (VAV) Units
Supply Air Temperature Sensor
An analog input device used with CV and VAV
applications that monitors the supply air temperature
for:
• supply air temperature control (VAV)
• supply air temperature reset (VAV)
• supply air temperature low limiting (CV)
• supply air tempering (CV/VAV)
It is mounted in the supply air discharge section of the
unit and is connected to the RTM.
Return Air Temperature Sensor
An analog input device used with a return humidity
sensor on CV and VAV applications when the
comparative enthalpy option is ordered. It monitors the
return air temperature and compares it to the outdoor
temperature to establish which temperature is best
suited to maintain the cooling requirements. It is
mounted in the return air section and is connected to
the ECEM.
Leaving Evaporator Temperature Sensor
An analog input device used with CV and VAV
applications that monitors the refrigerant temperature
inside the evaporator coil to prevent coil freezing. It is
attached to the suction line near the evaporator coil
and is connected to the MCM. It is factory set for 30°F
and has an adjustable range of 25°F to 35°F. The
compressors are staged "Off" as necessary to prevent
icing. After the last compressor stage has been turned
"Off", the compressors will be allowed to restart once
the evaporator temperature rises 10°F above the "coil
frost cutout temperature" and the minimum three
minute "Off" time has elapsed.
Entering Evaporator Temperature Sensors
Analog input devices used with CV and VAV
applications. This device is used in conjunction with
the Leaving Evaporator Temperature Sensor to prevent
the unit from running compressors with insufficient
charge.
G G e e n n e e r r a a l l I I n n f f o o r r m m a a t t i i o o n n
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