Trane CAH-SVX01A-EN manual Unit Operation, General Checks, Calculate Motor Voltage Imbalance

General Checks

•Ensure the unit has been installed level.

•Ensure supply-air and return-air ducts have been connected.

•Ensure damper operator motors and connecting linkage have been installed.

•Verify damper operation and linkage alignment.

•Check that air filters are in place and positioned properly.

•Remove any debris from the unit interior.

•Close and secure all unit access doors.

Note: UL-listed units require a removable latch on access doors. The door clip shipped with the unit meets this requirement.

•Inspect electrical connections to the unit and unit controllers.

–Connections should be clean and secure.

–Compare the actual wiring with the unit diagrams.

–Reference the appropriate controller manual for more details about starting units with factory-mounted controls.

•Leave this manual with the unit.

44

Startup

Unit Operation

Before complete startup, bump-start the unit and confirm the fan wheel rotates properly, as indicated by the rotation arrow located on the fan housing.

After initial startup:

•Calculate the motor voltage imbalance, notifying the power company to correct unacceptable imbalances.

•Periodically check the fan belt tension.

Calculate Motor

Voltage Imbalance

After startup, measure the motor voltage and amperage on all phases to ensure proper operation. The readings should fall within the range given on the motor nameplate. The maximum allowable voltage imbalance is 2 percent.

Voltage imbalance is defined as 100 times the sum of the deviation of the three voltages from the average, divided by twice the average voltage. For example, if the three measured voltages are 221, 230 and 227, the average voltage would be 226 volts. The percent of voltage imbalance is then calculated:

Voltage imbalance =	100A
	2--------------------------------------------------⋅AvgVoltage

where:

A = (226-221) + (230-226) + (227-226)

Voltage imbalance = 2.2% (not acceptable)

In the example, 2.2 percent imbalance is not acceptable and the power company should be notified to correct it.

￿WARNING 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.

CAH-SVX01A-EN