MINIMUM
DAMPER
POSITION
SETPOINT
FHC50 Only
The MIN CONTROL POS item is used to set the minimum
damper position. The minimum damper position allows the
setting of a minimum airflow through the fume hood. When the
fume hood exhaust volume needed to maintain the set face
velocity is less than the set minimum damper position (typically
sash closed), the damper maintains the minimum damper
position. Closing the sash further will result in an increase in the
face velocity above the control set point which may cause a
high alarm.
MAXIMUM
DAMPER
POSITION
SETPOINT
FHC50 Only
The MAX CONTROL POS item is used to set the maximum
damper position. The maximum damper position allows the
setting of a maximum airflow through the fume hood. When the
fume hood exhaust volume needed to maintain the set face
velocity is greater than the set maximum damper position
(typically sash open), the damper maintains the maximum
damper position. Opening the sash further will result in a
decrease in face velocity, which may cause a low alarm
indicating an unsafe hood condition exists.
MINIMUM FLOW
SETPOINT
FHC50 Only
The MIN FLOW item sets the minimum flow set point when the
NORMAL CONTROL MODE is set to VelSidewall, VelSashPos
or VelSide+Sash. When the fume hood exhaust reaches the
minimum flow set point, as the fume hood sash is lowered, the
controller will modulate the hood exhaust to maintain this
minimum flow.
WARNING: The Model FHC50 may not maintain the fume
hoods average face velocity at the SETPOINT item
value when a MINIMUM FLOW has been
programmed. The average face velocity may
exceed the SETPOINT item value, resulting in a
HIGH ALARM condition.
NOTE: The MINIMUM FLOW set point must be 50 cfm less
than the MAXIMUM FLOW set point.
To Next Page
Loading...
Need help?
General
