WattMaster VAVBOX - Manual (Page 20)

Technical Guide
VAVBOX Controller 20
There are 120 log positions available. Once the last (120th) position
has been recorded, the log jumps back to the first position and begins
overwriting the old data. 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 fixed items in the log are listed below:
•
Date
•
Time
•
Space Temperature
•
Active Cooling Setpoint
•
Active Heating Setpoint
•
Supply Air Temperature
•
Airflow on Pressure Independent Terminal Units
•
Damper Position
Note: For proper time and date stamping of the tenant log,
you must configure WMVAV Controller to broadcast the
time so that the VAVBOX 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 because there is no battery backed memory
on the VAVBOX controllers.
Force Modes or Overrides
The VAVBOX controller damper can be forced to one of several posi-
tions. These force modes aid the user during troubleshooting or air bal-
ancing, etc.
•
Force Damper Full Open (Ignores Airflow Reading )
•
Force Damper Full Closed (Ignores Airflow Reading )
•
Force to Maximum Airflow/Damper Setpoint
•
Force to Minimum Airflow/Damper Setpoint
•
Force to Fixed Airflow/Damper Setpoint
•
Force Damper to Re-Calibrate
The Force to Fixed Airflow/Damper mode also has a setpoint associ-
ated with it. This allows the user to provide a non-changing fixed amount
of air into the space that doesn’t affect the Minimum or Maximum
setpoints. That means the user doesn’t have to disturb the real minimum
and maximum setpoints to achieve a nonstandard setting during their
troubleshooting or air balancing modes.
The Force to Minimum mode uses the currently active minimum set-
ting based on the Vent, Cooling or Heating modes. Whatever mode the
VAVBOX controller is in, sets the minimum used by the force mode.
The damper force modes will remain in effect until cancelled by the
user, or until the power is removed. Unlike the WMVAV Controllers,
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.
Sequence Of Operations