Calibration, Operation Modes, and Control
This section provides information about the following:
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Calibration
The calibration sequence enables the controller to calibrate both, the air valve position and the
water valve position. Calibration takes place if auto-calibration is enabled and either a power cycle
or a transition from occupied to unoccupied has occurred.
Note: Whether or not auto-calibration is enabled, the controller initiates calibration on a
The building automation system is responsible for the staggering of the calibration sequence that
is needed between units. When auto-calibration is enabled, and a transition from occupied to
unoccupied occurs, the calibration sequence starts after a fixed delay of three (3) minutes. The
controller effective occupancy mode is unoccupied, but runs as if it is occupied during this three-
minute period.
The mode field of reported unit status reports calibration when the controller is in the calibration
sequence. If auto-calibration is disabled, the air valve and water valve are not driven closed and
the flow sensor zero flow voltage reading is not recorded. Refer to following table for calibration
actions.
I/O Device
Air valve
Flow sensor
Modulating hot water
reheat
Fan
Electric or On/Off hot
water
Occupancy Modes
The Symbio 210 controller has four (4) valid occupancy modes:
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Occupied Mode
Occupied mode is the normal (default) operating mode for occupied spaces or daytime operation.
When the controller is in the occupied mode, it uses occupied setpoints and is controlled by:
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40
"Calibration"
"Occupancy Modes," p. 40
"Space Temperature Control (STC) for Single Duct and Fan-powered Units," p. 42
"Ventilation Flow Control (VFC)," p. 50
"Flow Tracking (FTC)," p. 53
communicated application mode command.
Calibration Action Taken
Drive the air valve closed to the stroke time, plus 20
seconds.
Record the flow reading when the air valve is fully closed.
Drive the water valve closed for the stroke time, plus 20
seconds.
Enabled
Disabled
Occupied mode
Unoccupied mode
Occupied standby mode
Occupied bypass mode
Occupied space temperature control
Ventilation flow control (constant volume with discharge air temperature control)
Flow tracking control (has no occupancy)
Result After Calibration
Initialize the air valve position as closed when the
air valve is over-driven.
Subtract the zero flow reading from all subsequent
readings.
Initialize the water valve position as closed when
the water valve is over-driven.
Enabled
Enabled
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