Overriding Outputs; Diagnostics - Trane BCHE Installation, Operation And Maintenance Manual

Overriding Outputs

Analog and multistate value request points are included in
order to safely override outputs without disrupting TGP2
program operation. To override valves and dampers for
commissioning or testing purposes, access the following
®
points on the Tracer TU analog or multistate status
pages:
• Cool valve request
• DX cool request
• Heat valve request
• Electric heat request
• Economizer request
• Supply fan speed active
For more information, refer to: BAS-SVX20*-EN
Installation, Operation, and Maintenance: Tracer
B Programmable Controller

Diagnostics

Diagnostics are informational messages that indicate the
operational status of the controller. In response to most
diagnostics, the controller attempts to protect the
equipment by enabling/disabling, or by opening/closing
specific outputs. Other diagnostics provide information
about the status of the controller, but have no effect on
outputs. Diagnostics are reported in the order in which they
occur. Multiple diagnostics can be present simultaneously.
Diagnostic messages are viewed using the Tracer® TU
service tool or through a BAS.
Note: Tracer TU will report only active diagnostics.
Diagnostics Types
Diagnostics are categorized according to the type of
clearing method each uses and the type of information
each provides.
The diagnostic types are:
• Manual (latching) diagnostics
• Automatic (non-latching) diagnostics
• Smart reset diagnostics
• Informational diagnostics
Note: Clearing diagnostics refers to deleting diagnostics
from the software; it does not affect the problem that
generated the message.
BCX-SVX002A-EN
Manual (Latching) Diagnostics
Manual diagnostics (also referred to as latching) cause the
unit to shut down. Manual diagnostics can be cleared from
the UC400-B controller in one of the following ways:
• By using the Tracer® TU service tool to reset latching
diagnostics on the Alarms Status tab or by temporarily
overriding the Reset Diagnostic Request (bv/2) on the
Binary Status tab.
• Through a building automation system.
• By cycling power to the controller. When the 24 Vac
power to the controller is cycled OFF and then ON
again, a power-up sequence occurs.
Automatic (Non-latching) Diagnostics
Automatic diagnostics clear automatically when the
problem that generated the diagnostic is solved.
®
UC400-
Smart Reset Diagnostics
Smart Reset Diagnostics are latching diagnostics that will
auto-recover if the condition is corrected. After the
controller detects the first smart reset diagnostic, the unit
waits 30 minutes before initiating the smart reset function. If
another diagnostic of this type occurs again within 24 hours
after an automatic clearing, clear the diagnostic manually.
Informational Diagnostics
Informational diagnostics provide information about the
status of the controller. They do not affect machine
operation, but can be cleared from the controller using the
BAS or Tracer® SC.
Building Automation System
Some building automation systems can reset diagnostics in
the controller. For more complete information, refer to the
product literature for the building automation system.
Trane Service Tools
Tracer® TU can be used to reset diagnostics present in a
Tracer UC400-B controller.
Controller Diagnostics
The following table lists each diagnostic that can be
generated by the UC400-B controller, the diagnostic effect
on outputs (consequences), and diagnostic type.
Note: The generic binary output is unaffected by
Diagnostics and Troubleshooting
diagnostics.
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