Wiring Installation; Uc400 Controller Pre-Power Check-Out; Transformer Recommendations - Trane Tracer Uc

Wiring Installation

This section provides wiring guideline information about the following:
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UC400 Controller Pre-power Check-out

Carefully follow the check-out procedures below and read all warnings and notices.
Live Electrical Components!
During installation, testing, servicing and troubleshooting of this product, it may be necessary
to work with live electrical components. Have a qualified licensed electrician or other
individual who has been properly trained in handling live electrical components perform these
tasks. Failure to follow all electrical safety precautions when exposed to live electrical
components could result in death or serious injury.
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Transformer Recommendations

A 24 Vac power supply must be used for proper operation of the binary inputs, which requires 24
Vac detection. In addition, the spare 24 Vac outputs may be used to power relays and TRIACS.
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VAV-SVX07B-EN
"UC400 Controller Pre-power Check-out"
"UC400 Controller Power Wiring, " p. 14
"BACnet MS/TP Communication Link, " p. 16
"Application Wiring, " p. 22
Check the supply voltage at XFRM.
Note: Proper polarity must be maintained. The 24 Vac is the hot side (+) and
side (-) of the 24 Vac input.
Important: The UC400 controller cannot be powered from a common 24 Vac transformer that
is supplying power to a device containing a full-wave rectifier bridge in its power
supply. The acceptable voltage is 20.4 to 27.6 (24 Vac nominal). However, voltages
at either extreme may result in increased system instability.
Verify communications wiring has properly been terminated to link plus and negative at XFRM
24 Vac (+) and (-) terminals.
Note: Polarity must be maintained on the BACnet communications link.
Verify that the zone sensor connections are correct as detailed in the UC400 controller wiring
section.
If heat has been added to the unit, verify that the proper output connections are correct, as
detailed in the UC400 controller wiring section.
Verify that the tubing is properly connected to the differential pressure transducer.
AC transformer requirements: UL listed, Class 2 power transformer, 24 Vac ±15%, device
max load 24 VA. The transformer must be sized to provide adequate power to the controller (24
VA) and binary outputs loads.
CE-compliant installations: The transformer must be CE marked and SELV compliant per IEC
standards.
WARNING
is the ground
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