Trane VAV-UCM 4.2, Инструкция по установке и обслуживанию

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VAV-SVX01C-EN 61
Troubleshooting
• Measure the power input to TB1-1 (power) and TB1-2 (Common/ground) of the UCM board.
The supply voltage should be between 20 and 28 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. See
complete wiring diagrams,
Figure 44, p. 79 to Figure 51, p. 86 .
2. Communication link polarity is reversed.
• The yellow LED will be ON indicating a reversed polarity. Switch the communication link
connection.
3. UCM is not addressed correctly
• Verify the DIP switch settings on the UCM.
4. Communication link signal has interference
• Communication link should not be routed near or with any voltage source.
5. Incorrect wire used
• Recommended wire is twisted shielded pair. See Chapter 2 for the wiring specifications for
the UCM.
• Be sure all other recommended actions listed above have been taken. Disconnect the
communication link from the board and check the board's ability to communicate with the
Trane Rover/ EveryWare Software. If communications do not exist, the board is assumed
defective.
6. UCM not correctly addressed or two UCM's addressed the same
• Check the DIP switches on the first VAV box and remove the communication link from the
second VAV box.
7. Communication wiring error (shorts, open, or reversed polarity)
• Remove the communication link past the first VAV box and verify the polarity. Check
resistance across the communication wires for possible shorts or open circuitry.
8. Communication link failure/down
• One UCM failure can bring down all UCM communications. The link is set up as a daisy chain
see chapter 2 for details. If whole link is down remove sections of the comm. link from UCMs
to isolate portions of the link to find bad UCM(s). Start at the BCU/CCP and remove comm.
link from all units except first UCM and see if you can communicate with the one UCM. If
the UCM cannot communicate with BCU/CCP, check UCM with Rover. If you can
communicate with the UCM with Rover then the issue is in the BCU/CCP. If you can
communicate with UCM the problem is further down. Go half way down the link from the
BCU/CCP and remove the downstream half of the link and see if the communication comes
up with the still attached UCM's. If it does not, you know the bad UCM(s) are in the existing
attached link. If communication does come up then the issue is further down the link. Repeat
until UCM(s) bringing down comm. link are found.
9. Defective UCM board
Wired Zone Sensor Failure Procedures
In the event that the UCM reports an incorrect zone temperature, properly inspect the following:
1. Actual room temperature is higher or lower than what the UCM reads
• Check the location and installation of the zone sensor. Change the calibration factor in the
UCM setup screens.
Note: If Zone sensor is off more than ± 2 degrees continue to number 2.
2. Zone sensor wired incorrectly