Setpoint Adjustments - Honeywell EXCEL 5000 User Manual

EXCEL CARE CONTROL ICONS EXAMPLES

Setpoint Adjustments

Purpose During the Auto mode of operation, adjust the setpoint for a Time Program by ±7
Kelvin.
During the Day mode of operation, adjust a permanently assigned setpoint of 20C
(68F) by ±7 Kelvin.
During the Night mode of operation, implement a fixed setpoint of 12C (54F).
Control Icons Use the SWI, DIF, and MAT control icons.
Example This example uses the TF26 temperature selector device as an external setpoint
positioner. The TF26 has a rotary knob for adjusting the setpoint and a switch to
select mode of operation (Auto, Day, and Night).
The following diagram shows the characteristic curve of the TF26.
The voltage of the TF26 can move in the gray-shaded areas when the potentiometer
knob is turned. Setpoint adjustments of ±degrees Kelvin can be set in the Auto and
Day modes of operation.
In Auto and Day operation, the TF26 has linear characteristic curves that are
different only by their intersections with the axis. In Night operation, the TF26
supplies a voltage less than 0.25V.
The curve formula for Auto operation is:
auto = -8*(TW-7.39)-12
265 74-5577–33 (US)
EN2B-0184 GE51 R0518 (Europe)