FACTS Engineering Direct Logic 405, Manual

Page: 44 / 62

SUPPORTING LADDER LOGIC 3.6
SETPOINT RAMP AND SOAK
For each loop the user can program a Ramp or Soak of the SetPoint as shown in the following examples.
SetPoint Ramp
A ramp of the SetPoint is the changing from the current SetPoint to a specified final SetPoint over a
specified period of time.
In this example, the temperature is used as the initial SetPoint. It is obtained from the Temperature
Controller parameter table for loop 1, V5005. The final SetPoint is in V1400 and the ramp time, in
minutes, is stored in V1401.
The holding time at each step is fixed at one minute. X0 is a physical input that triggers the calculation
of the ramp step, X0 could be replaced by any C (control relay) controlled by the user's program. The
calculated ramp step is stored in V1402. The SetPoint is increased from the initial temperature value to
the final SetPoint value. The example could easily be modified to ramp the SetPoint down to some
lower final value.