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VAV/Zone Controller Package
SEQUENCE OF OPERATIONS
Internal Trend Logging
In order to retrieve and utilize these logs, a computer with Prism
2 computer software installed must be connected to the Orion
Controls System. The VAV/Zone Controller continuously main-
tains an Internal Trend Log, which records a fi xed set of values
at an interval confi gured by the user.
There are 120 log values available. Once all 120 log values have
been recorded, the oldest value is replaced by each subsequent
new value. This means the user is required to retrieve the logs at
an interval that is shorter than the duration of the last 120 logs.
Shown below are some log intervals and the duration of 120 logs.
1 minute interval ...................... 2 hour duration
15 minute interval .................... 30 hour duration
30 minute interval .................... 60 hour duration
60 minute interval .................... 120 hour duration
The fi xed items in the log are listed below with the column header
in parentheses:
Date (Date)
Time (Time)
Space Temperature (Space)
Active Cooling Setpoint (CoolSP)
Active Heating Setpoint (HeatSP)
Supply Air Temperature (SAT)
Discharge Air Temperature (DAT)
Airfl ow (Airfl ow) [P.I. Units Only]
Damper Position (Damper)
Proportional Heat (Heat)
Current Operating Mode (Mode)
Space Temperature Mode (SPCMode)
SAT Mode (SATMode)
Fan Status (Box)
Box Heat Stages (BoxHt)
Auxiliary Heat Stages (AuxHt)
NOTE:
For proper time and date stamping of the tenant
log, you must confi gure the Unit Controller to broadcast
the time so that the VAV/Zone Controllers can read it and
use it in their tenant and trend logs.
CAUTION:
These logs are subject to loss if a power
outage occurs.
Internal Trend Logs &
Force Modes or Overrides
Force Modes or Overrides
The VAV/Zone Controller damper can be forced to one of several
positions. These force modes aid the user during troubleshooting
or air balancing, etc.
Force Damper Full Open (ignores Airfl ow reading)
Force Damper Full Closed (ignores Airfl ow reading)
Force to Maximum Airfl ow/Damper Setpoint
Force to Minimum Airfl ow/Damper Setpoint
Force to Fixed Airfl ow/Damper Setpoint
Force Damper to Re-Calibrate
The Force to Fixed Airfl ow/Damper Mode also has a setpoint
associated with it. This allows the user to provide a non-changing
fi xed amount of air into the space that doesn’t aff ect the mini-
mum or maximum setpoints. This means the user doesn’t have
to disturb the real minimum and maximum setpoints to achieve
a nonstandard setting during their troubleshooting or air balanc-
ing modes.
The Force to Minimum Mode uses the currently active minimum
setting based on the Vent, Cooling, or Heating Modes. Whatever
mode the VAV/Zone Controller is in determines the minimum
used by the force mode.
The damper force modes will remain in eff ect until cancelled by
the user or until the power is removed. Unlike the Unit Control-
lers which require the initiating device to be present at all times
during a force mode, the damper force modes are more permanent
since they are less likely to damage any equipment. There are no
force commands available for the auxiliary relays.
