Trane TR200 - Page 199

Example 2: Multi-zone, multi setpoint
The previous example can be used to illustrate the use of multi-zone, multi-setpoint control. If the zones require
different pressures for each VAV box, each setpoint may be specified in par.20-21
Setpoint 1, par.20-22 Setpoint
2 and par.20-23 Setpoint 3. By selecting Multi-setpoint minimum , [5], in par.20-20 Feedback Function, the PID
controller will increase the speed of the fan if any one of the feedbacks is below its setpoint and decrease the
speed of the fan if all feedbacks are above their individual setpoints.
20-21 Setpoint 1
Range: Function:
0.000
Proc-
essCtrlU-
nit*
[-999999.999 - 999999.999
ProcessCtrlUnit]
Setpoint 1 is used in closed-loop mode to enter a setpoint reference that
is used by the adjustable frequency drive’s PID controller. See the de-
scription of par.20-20
Feedback Function.
NOTE: Setpoint reference entered here is added to any other references
that are enabled (see par. group 3-1*).
20-22 Setpoint 2
Range: Function:
0.000
Proc-
essCtrlU-
nit*
[-999999.999 - 999999.999
ProcessCtrlUnit]
Setpoint 2 is used in closed-loop mode to enter a setpoint reference that
may be used by the adjustable frequency drive’s PID controller. See the
description of
Feedback Function , par.20-20 Feedback Function.
NOTE: The setpoint reference entered here is added to any other references that are enabled (see par. group
3-1*).
20-23 Setpoint 3
Range: Function:
0.000
Proc-
essCtrlU-
nit*
[-999999.999 - 999999.999
ProcessCtrlUnit]
Setpoint 3 is used in closed-loop mode to enter a setpoint reference that
may be used by the adjustable frequency drive’s PID controller. See the
description of par.20-20
Feedback Function.
NOTE
The setpoint reference entered here is added to any other references that are
enabled (see par. group
3-1*).
Parameter Description
4-162 TR200 Programming Guide