Trane VAV-UCM 4.2, Инструкция по установке и обслуживанию

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10 VAV-SVX01C-EN
VAV Start Up/Check Out Procedure
Chapter Overview
This chapter contains information about the following:
• Unit 4.2 Pre-Power Check-Out
• Light Emitting Diode (LED) Operations
• Zone Sensor Check-Out
UCM 4.2 Pre-Power Check-Out
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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.
• Check the supply voltage at TB1. Proper polarity must be maintained. TB1-1 is the hot side (+)
and TB1-2 is the ground side (-) of the 24 VAC input. The UCM cannot be powered from a
common 24 VAC transformer that is supplying power to a device containing a full-wave rectifier
bridge in its power supply. The acceptable voltage is 20 to 28 VAC (24 VAC cataloged). However,
voltages at either extreme may result in increased system instability.
• Verify that communications wiring has properly been terminated at TB2-1 (+) and TB2-2 (-).
Polarity is very important on the communications link.
• Verify that the zone sensor connections are correct as detailed in the UCM wiring chapter.
• Verify that the proper unit DIP switch settings have been set on each UCM.
• Verify that the tubing is properly connected to the transducer.
Light Emitting Diode (LED) Operations
The UCM has one green LED located near TB3 and one yellow LED located near TB2 on the UCM
circuit board. These LED’s are used to help diagnose communication (yellow) or circuit board
problems (green).
The green LED (red on older boards) is a power indicator. It is steady on when the power is on and
the software is functioning correctly. If it blinks with a 1 second on 1 second off cycle when power
is applied, then the board is not functioning and must be replaced.
The yellow LED functions as the communication indicator. The indication from the yellow LED is
as follows:
:
Table 1. Green LED power function indication
LED State Indication
"On” Board functioning correctly
Blinking Board malfunction (Replace Board)
"Off” Board does not have power
Table 2. Yellow LED communication indicator function
LED State Indication
"On”
Incorrect (reversed) communication polarity, no connection, or
shorted lines.