Despatch 1500 Controller - Manual (Page 27)

Despatch/Watlow 1500 Control Instruction Manual Page 21
Wait Steps (Cont.)
The Wait Step does not allow the linear ramping path to
reach the new conditions, as a Set Point Step does. To
optimize control (reduce the overshoot and undershoot), a
Wait Step uses the PID Parameters to satisfy the wait
condition. In other words, select the step type which best
matches your needs.
Next Step
The Next step (NX) step is used to select the program step.
After the final prompt in each of the step types (SP, JL or
WT), pressing ENTER advances the processor to NX. At
the same time the STEP display will advance by one.
Pressing ENTER again will bring up SP, JL or WT if the next
step has no programmed information. If there is data in the
subsequent step, the processor will move to the first prompt
in that submode.
If you want a different step from NX, select the number of
the step you want in the DATA display with the
> key and ?
key, then press ENTER. Again, the processor will move to
one of the three step types if the step is blank, or to the first
prompt in the step type loop: S1, JS or W1.
Pressing FCTN at NX instead of ENTER will send the
processor back to the initial prompt in the current step.
Recycle Option
You may request that your program repeat indefinitely by
selecting RC=1 in the GA=5 area of the CHG PARA mode.
With the Recycle option active, you may expect to see
continuous activity as the program sequence repeats.
However, if your Step #1 is programmed as a Wait Step, the
processor will be waiting for a time or actual condition and
no action will be taking place.