Checking For An Open, Burnt, Or Shorted Centravac Motor Winding; Information On Tracer - Trane CVHE Troubleshooting Manual

Checking for an Open, Burnt, or Shorted
1 Remove power from the machine and remove the three main fuses.
2 Disconnect the top three leads from the motor lugs.
3 Verify the terminal to terminal and terminal to ground resistances are correct by using the
tables below.
For Low to Medium Voltage Machines (Less than 4160 V):
Meas. Chassis
Point GND
N/A
Chassis
GND
V x 1,000*
T1
V x 1,000*
T2
V x 1,000*
T3
V x 1,000*
T4
V x 1,000*
T5
V x 1,000*
T6
where:
∞ = Infinity
V = The rated motor voltage.
* The rated motor voltage multiplied by 1,000 is the minimum resistance that you should
measure here. The actual resistance that you measure will probably be higher.
For High Voltage Machines (4160 V and higher): Consult Trane Technical Service
for this information.

Information on Tracer

Tracer is automatically installed when it does control. If it only does monitoring, it will not
automatically install and, in fact, a loss of comm with Tracer will be called if a person manually
installs the Tracer option. If the TCI and/or Tracer option are automatically installed by hooking
them up, the CLD menus will be automatically changed to 'installed'. If loss of comm occurs with
the Tracer or TCI, UCP2 will default to front panel setpoints, but the diagnostic 'Tracer
Communications Lost' will be called at UCP2 and Tracer will not be de-installed. On a power up,
if the Tracer option was previously installed, the TCI module will call out a 'Tracer failed to
Establish Comm' if the Tracer does not take control within two minutes.
CVHE-SB-32A
CentraVac Motor Windings
T1 T2
V x V x
1,000* 1,000*
∞
N/A
∞
N/A
∞ ∞
∞
< 1 ohm
∞
< 1 ohm
∞ ∞
T3 T4
V x V x
1,000* 1,000*
∞
< 1 ohm
∞ ∞
∞
N/A
∞
N/A
∞ ∞
∞
< 1 ohm
T5 T6
V x V x
1,000* 1,000*
∞ ∞
∞
< 1 ohm
∞
< 1 ohm
∞ ∞
∞
N/A
∞
N/A
107