Issue
N
C.S.
04.03.20
Trading Estate Farnham Surrey England
Doc. No. TD 120
Page 8 of 25
SET UP (Continued)
5.5 Entering and Leaving Setup Mode.
Setup Mode is selected from Normal Mode by simultaneously pressing the UP and the SET push buttons (i.e. the two outside
ones). This causes the LED labelled PGAIN (short for Proportional Gain) to light continuously. In Setup Mode, each of the
parameters in the list below may be selected for adjustment by pressing the UP or DOWN push buttons as required. The
parameter selected is indicated on the positioner circuit by an LED lighting next to the parameter's name.
PGAIN - Proportional Gain
DAMP - Damping
CURVE - Non-Linear Curve Selection
LOW - Low Current Point Calibration
HIGH - High Current Point Calibration
POT - Feedback Potentiometer Bottom of Range Setting
When the required parameter has been selected for adjustment, the SET push button is pressed to allow adjustments to be
made – the LED next to the selected parameter starts to blink, to indicate that Adjust Mode is active. Operation in the Adjust
Mode for each parameter is described in the following sub-sections. To leave Adjust Mode, press the SET push button again –
this causes the LED to light continuously, and allows movement between parameters again.
Note: There is no Adjust Mode for the feedback potentiometer bottom of range setting, but the automatic end stop finding
sequence can be initiated when this parameter is selected.
To leave set up mode (when the adjustments have been made and the SET push button pressed to leave Adjust Mode), press
the DOWN push button repeatedly to move down the parameter's and off the end of the list – at this point the LEDs cease to
light, and the positioner is back in Normal Mode.
5.6 Automatic Endstop Finding Procedure.
The positioner can automatically calibrate itself to range between any mechanical end stops (either the built-in actuator stops, or
any external stops built into the application). During the finding sequence, the positioner moves the actuator up to the top and
bottom stops and records their positions. It then uses these positions as the HIGH and LOW positions in the calibration data, and
applies the existing values for HIGH and LOW current input. Note that if the positioner was reverse acting before the sequence,
it remains so after the sequence.
The End Stop Finding Sequence starts when the POT parameter is selected, and the UP and SET push buttons (i.e. the two
outside push buttons) are pressed simultaneously. The POT LED starts to blink, and the actuator moves steadily up scale from
its set position. When its movement is stopped by the the top physical end stop, the positioner waits briefly, then moves the
actuator steadily downscale until it runs against the bottom physical endstop, where again it waits briefly, and finally moves
quickly back to the set position. The calibration data is written to non-volatile memory while the actuator pauses at its bottom
stop.
If the positioner is in service on an application where excursions to the end stops will be disruptive, avoid initiating this sequence.
5.7 Proportional Gain and Damping Settings (for Smoothness and Sensitivity).
Select Setup Mode, and the first parameter selected is automatically PGAIN – Proportional Gain. Press the SET push button,
and the PGAIN LED will start blinking. The value of the parameter can now be increased or decreased by pressing the UP or
DOWN push buttons as required. There are twenty nine (29) PGAIN settings which can be selected, the setting altering by a
factor of about 1.1 each time the UP or DOWN button is pressed. The default setting lies in the middle of the range, giving
fourteen settings above and fourteen below. Any button presses beyond the last (fourteenth) will have no effect.
Note: As soon as the UP or DOWN push button is pressed, the new PGAIN value is stored in non-volatile memory and is
retained even if the positioner is de-energised before leaving Adjust and Setup Modes.
Title : Installation, Operation & Maintenance Instructions – Digital EL Positioner
N – AR7059 / M – AR6971 / L - AR6419 / K - AR6347 / J-AR6096 / H – AR 6082 / G – AR 5487 / F – AR 5608 / E - AR 5293
