Controller Communication Loss - Trane Symbio 210 Installation, Operation And Maintenance Manual

Troubleshooting

Controller Communication Loss

Live Electrical Components!
Failure to follow all electrical safety precautions when exposed to live electrical components
could result in death or serious injury.
When it is 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.
In the event of communication loss (no activity on the LINK or IMC LEDs), check the following:
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The TX LED blinks green at the data transfer rate when the Symbio 500 controller transfers data to
other devices on the link.
The RX LED blinks yellow at the data transfer rate when the Symbio 500 controller receives data
from other devices on the link.
Check for incorrect supply voltage/no voltage.
– Check Marquee LED for the following:
• Displays solid green when the Symbio 500 controller is powered and operating normally.
• Displays solid red when the Symbio 500 controller is powered, but represents low power or a
malfunction.
• If marquee LED is solid red, check incoming power. Measure the power input to Symbio 500
controller on XFMR 24 Vac input and .
• The supply voltage should be between 20.4 to 27.6 Vac (24 Vac cataloged). However,
voltages at either extreme may result in system instability.
• If no voltage, check up stream of controller to see were voltage has been interrupted.
Check for correct addressing on the Symbio 500 controller.
Each Symbio 500 controller on the BACnet link must have a unique rotary switch setting,
otherwise communication problems will occur. There are three rotary switches on the front of the
Symbio 500 controller. Use these switches to define a three-digit address when the Symbio 500
controller is installed in a BACnet system (for example, 107, 120, and so on), whether with other
Trane BACnet controls or controls from another vendor. This three-digit rotary switch setting is
used as both the BACnet MAC address and the BACnet Device ID.
Note: Valid addresses are 001 to 120. Sequential addressing without gaps is recommended.
– Verify that there are no duplicated addresses on the communication link.
Check for alarms or diagnostics with Tracer TU service tool, and check that the communication link
avoids interference. Communication link should not be routed near or with any voltage source.
The following wiring best practices are recommended:
– Strip no more than 2 inches (5 cm) of the outer conductor of shielded wire.
– Avoid sharing 24 Vac power between unit controllers.
– Ensure that 24 Vac power supplies are consistently grounded. If grounds are not maintained,
then intermittent or failed communication could result.
Check that twisted shielded pair wiring is used and observe the following guidelines.
Connect the shield portion of the wire at the first unit controller in the link.
Tape back the shield at the end of the unit controller line.
Wire together and tape all other shields at each unit controller.
Check application version and build or download the latest application version using the Tracer TU
service tool.
Note: For instructions on how to use Tracer TU, refer to the Tracer TU Online Help and the Tracer
TU Service Tool Getting Started Guide (TTU-SVN02).
If communication loss persists, we recommend connecting to the link with Serial Spy MS/TP
analyzer to review the token passing. For detailed instructions about use, analysis and Comm link
WARNING
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