Despatch 1500 Controller - Manual (Page 21)

Despatch/Watlow 1500 Control Instruction Manual Page 15
Blank Step
Any unprogrammed step is first a Blank Step before
information entered makes it a Set Point, Jump Loop or Wait
Step.
In normal programming, only the last step in the program
remains a Blank Step. A Blank Step halts the processor. If,
however, the RECYCLE option was selected in the CHG
PARA mode, the program will return to Step #01 and repeat.
When programming a HAST chamber, a Blank Step is not
used. A Jump Step is used to jump over blank steps to
ensure the program will not stop until reaching steps 47-51
required for cooldown and shutdown.
Set Point Step
The existing start conditions for each step depend upon the
programmed step previously performed by the Watlow 1500.
The desired end conditions for each step are also
programmed.
During any set point step, the Watlow 1500 follows a linear
path between the existing start conditions and the desired
end conditions. When programming set points in the
Watlow 1500, it is important to keep track of the ramping
conditions at the start of a step and at the end of a step.
To clear a step:
1. Place the controller in halt by pressing the RUN/HALT
key until RUN/HALT LED is lit.
2. Place the controller in the desired step to be cleared.
3. Press the CLEAR pushbutton.