Tracer UC 400 Controller
UNT-SVX07E-EN
143
LED Activity
There are 15 LEDs on the front of the Tracer UC400
controller. The following table provides a description of
LED activity, an indication or troubleshooting tip for each,
and any related notes.
Table 85. Fresh air damper stays closed
Probable Cause
Explanation
Normal operation
The controller opens and closes the fresh air damper based on the controller’s occupancy mode and fan status.
Normally, the fresh air damper is open during occupied mode when the fan is running and closed during unoccupied
mode.
Warmup and cooldown
The controller includes both a warmup and cooldown sequence to keep the fresh air damper closed during the
transition from unoccupied to occupied. This is an attempt to bring the space under control as quickly as possible.
Requested mode: off
It is possible to communicate the operating mode (such as off, heat, cool) to the controller. When off is communicated
to the controller, the unit closes the fresh air damper.
Manual output test
The controller includes a manual output test sequence that verifies analog and binary output operation and associated
output wiring. However, based on the current step in the test sequence, the fresh air damper may not be open. Refer
to
“Manual Output Test,” page 137
.
Diagnostic present
A specific list of diagnostics effects fresh air damper operation. For more information, see
“Diagnostics and
Troubleshooting,” page 129
.
Unit configuration
The controller must be properly configured based on the actual installed end devices and application. When the unit
configuration does not match the actual end device, the damper may not work correctly.
No power to the controller
If the controller does not have power, the fresh air damper does not operate. For the controller to operate normally,
a 24 Vac input voltage must be applied. When the green LED is off continuously, the controller does not have sufficient
power or has failed.
Unit wiring
The wiring between the controller outputs and the fresh air damper must be present and correct for normal damper
operation. Refer to the unit wiring diagrams on the unit.
Tracer UC 400 Controller
Diagnostics and Troubleshooting
Table 86. LED activity and troubleshooting tips for Tracer UC400 controller
LED Name
Activities
Indication and Troubleshooting Tips
Notes
Marquee LED
Shows solid green
when the unit is
powered
and no
alarm exists
Indicates normal operation
When powering the UC400 and expansion module, the
Marquee LED will blink
RED
, blink
GREEN
(indicating
activated and controller/expansion module are
communicating), and then stay
GREEN
CONTINUOSLY
(indicating normal power operation).
Shows blinking
green during a
device reset or
firmware
download
Indicates normal operation
Shows solid red
when the unit is
powered
, but
represents low
power or a
malfunction
If low power
; could be under voltage or the
microprocessor has malfunction. Measure for the
expected value range. For more information, refer to
Installation, Operation, and Maintenance: Tracer
UC400 Programmable Controller
(BAS-SVX20C-EN,
or the most recent version).
If malfunction
; un-power and then re-power unit to
bring the unit back up to normal operation.
Shows blinking
red when an
alarm
or fault
exists
An alarm or fault condition will occur if the value for a
given point is invalid or outside the configured limits
for the point. Alarm and fault conditions vary, and they
can be configured by the programmer.
LED not lit
Indicates power is OFF or there is a malfunction
OFF
or
malfunction
; cycle the power. For more
information, refer to
Installation, Operation, and
Maintenance: Tracer UC400 Programmable Controller
(BAS-SVX20C-EN, or the most recent version).
