Commissioning Instructions

Step 8 – Fault detection and diagnostics parameters
15
Unrestricted
A6V12035398
Supply VAV air flow fault diagnostics
Configuration:
Descriptor
Object
Type
Default
Value
Units
Enumeration
Abbreviated Name
(BACnet)
Supply VAV air flow fault
MCalcVal
Normal
1: Normal
2: Hi Flow
3: Low Flow
SU FLOW FLT
(SuAirFlFlt)
Supply VAV unstable control fault
BCalcVal
Normal,
Fault
SU UNSTB FLT
(SuUnstblCtlFlt)
Supply VAV unstable control reset
MTrgVal
Ready
1: Ready
2: Reset
SU UNSTB RST
(SuUnstblCtlRst)
Supply VAV airflow fault tolerance
Difference between measured airflow
and setpoint required to trigger the air
flow setpoint fault.
ACnfVal
100
(170)
(47)
Ft3/min
(m3/hr)
(lps)
(SuAflFltTol)
Supply VAV air flow fault delay
The duration the air flow setpoint
tolerance must be exceeded to trigger
the air flow setpoint fault.
ACnfVal
600
s
(SuAflFltDly)
Supply VAV position tolerance
Damper needs to move this % before it
is considered an oscillation.
ACnfVal
2
%
(SuPosTol)
Supply VAV change limit [count]
Number of oscillations needed to
trigger the fault alarm.
ACnfVal
5
(SuPosChgLim)
Supply VAV change time limit
The oscillation counter will be reset, if
the position tolerance has not been
exceeded for this length of time.*
ACnfVal
600
s
(SuPosChgTiLim)
* For example, if 4 oscillations occur, but a fifth oscillation is not detected before 600 seconds elapse, then the counter is
reset to 0.