Trane Precedent YHJ072A Installation, Operation And Maintenance Manual page 41

Control Power Transformer
The 24 volt control power transformers are to be used only
with the accessories called out in this manual.
Transformers rated greater than 50 VA are equipped with
internal circuit breakers. If a circuit breaker trips, turn "Off"
all power to the unit before attempting to reset it.
WARNING
Hazardous Voltage!
Failure to disconnect power before servicing could
result in death or serious injury.
Disconnect all electric power, including remote
disconnects before servicing. Follow proper lockout/
tagout procedures to ensure the power can not be
inadvertently energized. Verify that no power is
present with a voltmeter.
The transformers are located in the control panel. The
circuit breaker is located on the right side of the transformer
and can be reset by pressing in on the black reset button.
Controls using 24 VAC
Before installing any connecting wiring, refer to the
Dimensions and Weights chapter for the electrical access
Figure 54. Low voltage wiring — B cabinet
RT-SVX075A-EN
locations provided on the unit and
conductor sizing guidelines, and;
1. Use copper conductors unless otherwise specified.
2. Ensure that the AC control wiring between the controls
and the unit's termination point does not exceed 2.5
ohms/conductor for the length of the run
NOTICE
Component Failure!
Resistance in excess of two and a half (2.5) ohms per
conductor could result in component failure due to
insufficient AC voltage supply.
Do not exceed two and a half (2.5) ohms per
conductor for the length of the run.
Note: Be sure to check all loads and conductors for
grounds, shorts, and mis-wiring.
3. Do not run the AC low voltage wiring in the same
conduit with the high voltage power wiring.
4. Route low voltage wiring per illustrations below.
Installation
Table 7, p. 43 for AC
41