Honeywell EXCEL 5000 User Manual page 27

EXCEL CARE CONTROL ICONS ALPHABETIC REFERENCE
The next diagram illustrates the use of a Cascade controller to perform the same
functions. The CAS controller contains two PI controllers in a "cascade"
arrangement. The X variable reads the master-controlled variable (room
temperature). The XH variable reads the fresh air temperature (auxiliary-controlled
variable). The W variable is the room temperature setpoint (reference variable).
Setpoint Reset Example This example shows how to use cascade control to reset a discharge air controller
setpoint up to 95F (35C) if room temperature falls below its setpoint to 65F (18C).
The submaster controls the controller setpoint. The output of the master controller
resets the setpoint of the submaster up and down.
Parameters for the master controller are:
29 74-5577–33 (US)
EN2B-0184 GE51 R0518 (Europe)