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3 setup loop control parameters, 3 setup loop control parameters -23 – Watlow 12LS Controller User Manual

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4-23

When the PV readout is reading below the true known PV level, add that amount to the High and Low PV scaling.
When the PV readout is reading above the true known PV level, subtract that amount from the High and Low PV
scaling.

Example: A J T/C is reading 396 when true temperature is 400.

Set the High PV to 1404 and the Low PV to -346.

Example: A J T/C is reading 302 when true temperature is 300.

Set the High PV to 1398 and the Low PV to -352.

CAUTION! ADJUSTING THE SCALING VALUES WILL EFFECT THE CALIBRATION OF THE INPUT
RANGE. DO NOT ADJUST THE RDG VALUES OF THE T/C RANGES. INCORRECT SCALING VALUES
WILL GIVE ERRORS IN READING OF THE PROCESS VARIABLE.

4.5.3 SETUP LOOP CONTROL PARAMETERS

Press YES at this prompt to access menus to change control parameters for both the heat and cool outputs of the
selected loop, including :

o Proportional Band
o Integral
o Rate
o Output Filter
o Spread between heat and cool outputs

The top line of all displays will appear as one of those shown below, depending on whether the heat or cool control
output is being programmed. In all cases the LL represents the loop number displayed in the upper left hand corner.

|----------------| |----------------|
¦LL HEAT CONTROL ¦ ¦LL COOL CONTROL ¦
¦ ¦ ¦ ¦
|----------------| |----------------|

The heat output parameters are programmed first, then the same parameters for the cool output.

|-----------------------------------------------------|
¦ NOTE: If the COOL output PB is set to OFF the loop ¦
¦becomes a single output channel and no longer will ¦
¦function as a heat/cool loop. Further programming ¦
¦ of COOL output parameters is skipped and the display¦
¦ returns to the SETUP LOOP CONTROL PARAMS ? prompt. ¦
|-----------------------------------------------------|