Electro-Pneumatic Positioners
Connection - Ground
①
Open positioner's body cover.
②
Locate
the
poles
and
connect
them
properly. <Figure 17>
- 14 -
<Figure 17>
Adjustment
Adjustment - Zero Point
①
Set supply signal at 4mA or 20mA and rotate
adjuster clockwise or counter-clockwise to adjust
actuator's initial point. When setting initial point, the
specification of valve and system must be taken
account.
Please refer to <Figure 18> for
increase/decrease of the zero point.
<Figure 18>
②
When single acting actuator with spring is used, please check if the pressure level which
is indicated on the positioner is same to the supplied pressure level.
Adjustment - Span
①
After setting zero, supply 20mA or 4mA of
signal. Check the actuator's stroke. If the stroke
is too low, adjust the span towards '+' direction.
On the other hand, if the stoke point is too high,
adjust the span towards '-' direction. <Figure
19>
②
Changing span point affects zero point setting.
So zero setting must be set again.
After
setting zero point, confirm the span point. This
step must be repeated until both points are
properly set.
③
After setting is completed, tighten Lock Screw.
<Figure 19>
<Figure 19>
