Watlow 12LS Controller - Manual (Page 108)

G-3
Scaling Enter two values of unscaled process readings RDG
and their corresponding scaled process values PV.
Try to have as near as possible to zero and full
scale. Once entered the 8LS calculates linear
scaling from these values and scales all
subsequent measured data. This should be entered
prior to any other loop data.
Setpoint The desired control setting. This will be in
engineering units after scaling.
Spread For heat/cool dual output loops, this entry offsets
the heat and cool control points from the entered
setpoint. The heat will start to control when the
process is one half the spread below the setpoint.
The cool will start to control when the process is
one half the spread above the setpoint. When the
process is between the spread values there is no
control output.
TI Integral or Reset of the PID. The time constant is
in seconds.
TD Derivative or Rate of the PID. The time constant
is in seconds.
Units Three characters that will appear in the display
next to the process variable.