Red Lion TSC - Manual (Page 69)

ON/OFF CONTROL
The controller can operate in the
ON/OFF control mode by setting the
proportional band = 0.0. The ON/OFF
control hysteresis band (CHYS) parameter
can be used to eliminate output chatter
around setpoint. The cooling output can
also be used in the ON/OFF control by
setting the relative gain = 0.0
The phase of the control action can be
reversed by the output control action
parameter. ON/OFF control is usually
characterized by significant temperature
oscillations about the setpoint value. Large
control hysteresis values makes the
oscillations larger. ON/OFF control should
only be used where the constant oscillations
have little effect on the process.
-67-
MAIN CONTROL OUTPUT (OP1) COOLING OUTPUT (OP2)