Installation and Maintenance Manual

Diagnostics
126 UNT-SVX07D-EN
Troubleshooting (ECM)
Notes:
• The new Trane BLDC system is a closed loop system
that has equipment protections and envelope
enforcements. Do not assume that the motor has failed
without first consulting the ECM engine status/
diagnostics screen. In many cases, the engine shuts
down the motor operation and locks it out to prevent
equipment damage.
• Electric Heat operation and Changeover Coil control on
CSTI units are co-coordinated by the ECM engine
board. Changeover function on Tracer ZN units can
also be affected by incorrect configuration of the ECM
engine or improper wiring of terminals to analog
input 1 on the Tracer ZN controller (polarity
sensitivity).
• The mini-access lid on the front of the main control
panel lid has the ECM engine troubleshooting/setup
guide affixed to the back of the lid. This guide is unit-
specific and should be consulted before determining
the disposition of a unit.
General Information (ECM)
The ECM engine oversees and monitors all motor
operations and changes to speed resulting from:
• Direct Fan Speed Requests
– Customer Fan Speed Switches
–
Thermostat Fan Speed, On or 0–10V requests
– Automatic Fan Request from Tracer ZN / UC
controllers
• Indirect Fan Speed Requests
– Electric Heat requests will bring the fan
to the
proper speed.
• Conflicting Fan Speed Requests
– If two or more commands are received (direct or
indirect), the
fan will honor the higher speed
requested.
Note: In some cases, indirect requests will result in fan
behavior change regardless of whether the end-
device fails to actuate (due to device failure, or
safety/down-stream lockouts).
The ECM engine board also coordinates the operation of
Electric Heat, Electric/Hydronic Heat lockouts, and CSTI
Changeover coil operation.
Troubleshooting Information (ECM)
General system troubleshooting tips (ECM)
• ECM engine configuration must perfectly match the
factory-supplied ECM.
– Refer to “
ECM Overview and Setup,” p. 53 for
troubleshooting configuration of the engine board.
• The ECM engine will display troubleshooting
inform
ation, and contains dual tachometers to aid in
performance verification.
• Under normal circumstances, the
ECM engine display
will display the operational status of the motors and
electric heat circuit/sensors, however, a malfunction
will drive a priority display mode that will present the
error code instantly to the screen. The error must be
cleared by solving by powering down, removing the
cause of the problem and restarting the engine board.
• Engine Label setup document (af
fixed to the back of the
low voltage access lid) should be used to verify engine
configuration settings.
• For proper operation of the system, all plugs must be
firml
y seated in all boards and motors. Insecure
WARNING
Hazardous Voltage w/Capacitors!
Disconnect all electric power, including remote
disconnects and discharge all motor start/run
capacitors before servicing. Follow proper lockout/
tagout procedures to ensure the power cannot be
inadvertently energized. For variable frequency drives
or other energy storing components provided by Trane
or others, refer to the appropriate manufacturer’s
literature for allowable waiting periods for discharge of
capacitors. Verify with an appropriate voltmeter that all
capacitors have discharged. Failure to disconnect
power and discharge capacitors before servicing could
result in death or serious injury.
WARNING
Safety Alert!
You MUST follow all recommendations below. Failure
to do so could result in death or serious injury.
• The BLDC motors contain capacitors which store
residual energy. Please keep clear of the fan wheels
for 5 minutes after the power has been removed from
the system, as a power request with the motor
powered off, could result in a very short period of
actuation. Unplugging the motor is adequate to
ensure that there will be no power request.
• The adapter boards contain high voltage.
Configuration adjustments to the ECM engine board
should be made through the SMALLER of the two
low-voltage lids on the front of the control panel,
through the low-voltage insulation/shielding.
• Initial hookups to the CSTI and standard adapter
boards, including low voltage interconnections,
must be made with the power off.
• Do not make connections to the motors or the
adapter boards while power is ON. Do not remove
connections to the motor or the adapter boards while
the power is ON.
UNT-SVX07_-EN.book Page 126 Friday, April 27, 2012 9:40 AM