Glossary - Airstream TC5-2V4SA User Manual

GLOSSARY

BANDWIDTH: The temperature interval within which the variable-speed
fans of a given stage increase or decrease in speed proportionally to the
temperature.
CASCADING HEATERS: Heaters operate in a sequence. As the
average room temperature drops, additional heaters are turned on as
needed.
CURTAIN DEAD BAND: The dead band is the temperature difference
between the opening and closing temperatures of the curtains. Within
this interval, the curtains are at rest.
DEFAULT VALUE: A typical parameter setting defined at the factory.
DIFFERENTIAL: The differential is the temperature difference between
the moment the constant-speed fans or heating units of a given stage
start running and the moment they return to a stop.
HYSTERESIS: A hysteresis is used to smooth the transition from one
state to another. For example, when the temperature drops to the cut-off
point for a stage of constant-speed fans, the fans will actually be cut off at
slightly less than the cut-off point. This way, if the temperature fluctuates
around the cut-off point without dropping significantly below it, the control-
ler will not oscillate between two states. For example, if the hysteresis is
0.3°F and the stage 2 fans are programmed to be cut off at 75°F, the cut-
off will actually occur at 74.7°F.
MINIMUM VENTILATION CYCLE: When the room temperature is below
the set point, the Stage 1 fans operate intermittently to provide minimum
ventilation to the room.
MINIMUM VENTILATION SPEED CURVE: When Stage 1 operates
variable-speed fans, they will run at minimum speed during the minimum
ventilation cycle. The user can define a minimum ventilation speed curve
to adjust the Stage 1 minimum speed automatically over a given time
period. The minimum speed increases over time as the animals grow.
OFFSET: An offset is a temperature difference from the set point that
normally defines a cut-off point for a stage operation. For example, a
heater offset of 2°F means the heaters will turn off at 2°F below the set
point.
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TC5-2V4SA rev.06