Trane Tracer VV550 User Manual

CNT-SVX17G-EN 33
Sequence of Operations
There is no impact on the reheat operation during airflow override. Parallel fans are
turned Off during the drive to configured maximum airflow or open to prevent physical
damage to the back-draft door.
Receiving the communicated flow override OFF request releases the air valve back to the
controller for normal operation. The controller automatically exits the airflow override
mode, changes communicated flow override to OFF, and reverts back to normal
operation if the configured manual override time (default = 600 minutes [10 hours])
elapses since the last valid reception of communicated flow override.
Fan Override
The fan can be remotely controlled by the use of the communicated fan speed command.
This variable can be used to request modulating speeds from 0% to 100% in 0.5%
increments. Table 24 shows the affect of the variable on controller operation.
Table 24.Fan override controller operation
Communicated
fan speed
command
No heartbeat
On/Off fans
series or
parallel
Air valve Reheat
Off Off Normal Local electric: Off;
Other: normal
On, 100% On Normal Normal
On 0.5% to 99.5% On Normal Normal
Normal Operation
Normal operation is the lowest priority sequence. The controller is functioning normally
when it is operating in one of the three control modes (space temperature control,
ventilation control, or flow tracking control) and in one of four occupancy modes
(occupied mode, unoccupied mode, occupied standby mode, or occupied bypass mode).
4 = Open
Fully open all air valves
Normal Open Series normal
Parallel Off
5 = Close
Fully close all air valves
Normal Close Normal
6 = Minimum Normal Control airflow to the configured minimum
ai
rflow
Normal
7 = Maximum Normal Control airflow to the configured maximum
ai
rflow
Series normal
Parallel Off
Other enumeration Normal Normal Normal
Note: Local electric reheat is turned Off when the primary airflow rate falls below the configured minimum local heating airflow
minus 3% of the configured nominal airflow.
Table 23.Airflow override controller operation (continued)
Communicated flow override Local or
remote
reheat
Air valve Fan

Trane Tracer VV550 Specifications

General

Brand	Trane
Model	Tracer VV550
Category	Controller
Language	English