Trane Tracer VV550 User Manual

32 CNT-SVX17G-EN
Sequence of Operations
Overrides: Water Valve, Flow, Fan
These three overrides have the same priority in the control sequences:
Water Valve Override
When the controller responds by driving the outputs within five seconds of receiving the
communicated valve override network variable. The actuators are driven as quickly as
possible to the correct position.
Water valve override has many enumerations. See the LonMark
®
Space Comfort
Controller (SCC) functional profile for a complete list of all the water valve override
enumerations. Table 22 shows the three supported water valve override requests. Other
enum
erations are treated as not valid.
Table 22.Water valve override controller operation
Communicated valve override
Local
reheat
Air valve Fan
0 = Off, normal, or not valid Normal Normal Normal
4 = Open, fully open all valves Open Normal Normal
5 = Close, fully close all valves Closed Normal Normal
Other enumeration Normal Normal Normal
There is no impact on the air valve or fan operation during water valve override.
Receiving the communicated valve override OFF re
quest releases the water valves back
to the controller for normal operation. The controller automatically exits the water valve
override mode, changes the communicated valve 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 receipt of a communicated valve override.
Flow Override
The controller responds by driving the outputs within 5 seconds of receiving the
communicated flow override network variable. The actuators are driven as quickly as
possible to the correct position. The local zone sensor module flow overrides (single star
and double star) have priority over the communicated flow override.
The airflow override network variable (communica
ted flow override) has many
enumerations. See the LonMark
®
Space Comfort Controller functional profile for a
complete list of all the airflow override enumerations. Table 23 shows the supported
airf
low override requests. Other enumerations are treated as not valid.
Table 23.Airflow override controller operation
Communicated flow override Local or
remote
reheat
Air valve Fan
0 = Off
Normal or not valid
Normal Normal Normal
3 = Flow percent Normal Control airflow to the requested percentage of
the c
onfigured maximum airflow
Normal

Trane Tracer VV550 Specifications

General

Brand	Trane
Model	Tracer VV550
Category	Controller
Language	English