Becker HPP-SB, Инструкция по эксплуатации

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Your HPP-SB series positioner will arrive
factory adjusted for your particular application.
The use of the following adjustment proce-
dures will only be necessary once a rubber
goods replacement kit is installed or any other
time the positioner is disassembled
.
Adjustment Procedure
The Becker HPP-SB Positioner has three (3)
adjustment devices:
•
The adjustment drum adjusts the dead-
band.
•
The range spring adjusts the span.
•
The adjustment screw adjusts the bias.
Note:
Before making any adjustments, be
sure the positioner supply pressure and dis-
charge pressure are at the designated set-
tings.
HPP-SB Positioner
Adjustment
5. If the actuator is equipped with an MCV-3
Manual Control Valve), place the left MCV-
3 handle in the manual position. If the ac-
tuator is not equipped with an MCV-3, use
the block valve (1/4 “ ball valve) installed
between the positioner output and the ac-
tuator. Once the actuator has reached its
desired position (based on the mid-signal
applied to the instrument port – Step 4),
place the block valve in the closed posi-
tion.
6.
Check the exhaust port of the positioner
(remove any tubing if necessary). If ex-
haust port bleeds gas, turn the
adjustment
drum (decreasing numbers) until the ex-
haust port stops bleeding gas. If the ex-
haust port does not bleed gas, turn the
ad-
justment drum (increasing numbers) until
the exhaust port starts to bleed gas and
then back the drum off slightly until the
point in which it just stops bleeding. After
each adjustment, fluctuate the input signal
to allow output pressure to swing in both
directions.
Deadband Setting
1. Remove the set screw from the drum and
turn the deadband adjustment drum
(increasing the numbers) until the drum
can no longer turn. Then turn the
adjust-
ment drum one full turn in the opposite di-
rection (use the numbers on the drum as a
guide).
2. If not already attached, wind 3-4 coils of
the range spring onto the retainer.
3. If not already adjusted, set the bias adjust-
ment screw in the middle of its travel
range.
4. Set the instrument signal pressure at the
midpoint of its range (e.g.. 9 psig for a 3-15
psig range, 18 psig for a 6-30 psig range).
Stroke the actuator to an intermediate po-
sition.
7. The unit is properly adjusted if an increase
or decrease in the input signal by .1 psig
causes the output gauge to swing in either
direction.
Signal Line from Control-
HPP-SB 6 September 1999