AEC WD 350 through WD3000 Dehumidifying Dryers - Manual (Page 67)

Proportional Band
When displays on the PV screen, you can then change the proportional band (P constant)
by pressing and . The new value displays on the SV screen. You can set it in a range
from 0.1 ° to 999.9 ° C/ ° F in units of 0.l ° C/ ° F. The value is set at the factory to 40.0 ° C/ ° F, but this
changes as the controller auto-tunes itself.
Integral Time
When displays on the PV screen, you can change the integral time (I constant) by
pressing and . You can set it in a range from 0 to 3,999 seconds in units of 1 second.
The value is set at the factory to 233 seconds, but this changes as the controller auto-tunes itself.
Derivative Time
When displays on the PV screen, you can change the derivative time (D constant) by
pressing and . You can set it in a range from 0 to 3,999 seconds in units of 1 second.
The value is factory-set to 40 seconds, but this changes as the controller auto-tunes itself.
Manual Reset Value (%)
When using P or PD control (i. e. I = O), the process value may stabilize at a value above or
below the set point of the manual reset value, which has a factory default setting of 50%. You
can adjust it upward to eliminate droop or downward to eliminate overshoot.
Note: The
P , I , D , and OFR parameters are not accessible when the control mode is set to PID
with fuzzy self-tuning; P, I, and D are set automatically to optimum values based on
current process conditions determined by the controller.
Page 66 WDMR and WDFR Series Dehumidifying Dryers