Watlow Series 982 - Manual (Page 128)

9.14 WATLOW Series 982 User’s Manual
Software Features, Chapter 9
Software
Slidewire Feedback
Overview
The Series 982 can control the position of a valve with a slidewire feedback
position indicator. The controller senses the resistance of the slidewire and
compares it to the range low and range high settings to determine the
valve position. The controller compares this to the percent output and
takes action to match the two by opening or closing the valve.
Set the hunt [Hunt] parameter to limit valve hunting. The value is set for
the percent of output (0.0 to 100.0). When the valve is within this dead
band, a change in output greater than half the hunt parameter is required
to trigger action. If the valve’s momentum causes it to “coast” after the
contact opens, try increasing the {SHyS} value. This determines the turn-
off point. Output 1 responds to “close” commands and output 2 responds
to “open” commands.
Requirements
A slidewire configuration uses at least two inputs and two control outputs.
Input 2 must be a slidewire input (98_C-_3__-____). Outputs must be com-
patible with the slidewire valve actuators.