Beck 14-100, Инструкция по эксплуатации

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16
80-1403-01, Rev. 3
START-UP INSTRUCTIONS
After the actuator is mounted and its wiring
connections are made, it is ready to be tested for
proper operation.
Turn on the power supply. Operate the
actuator with the Handswitch and run it through
its full stroke, both directions. Observe that
the actuatorn device travels through its desired
stroke. If satisfactory, set Handswitch at the
“AUTO” position.
Turn on the controller and operate the
actuator by varying the control signal. Check
that the valve strokes in the proper direction
for a change in control signal. An increasing
control signal retracts the shaft and opens the
valve. With a 100% signal, the actuator is fully
retracted. If the valve does not stroke in the
proper direction, first check for proper wiring
connections and verify the control signal at the
actuator. If the wiring is correct, then reverse the
direction of travel (see page 29).
Valve Seating Adjustment
The actuator has a Tight-Seater™ attached
to its output shaft. The Tight-Seater™ allows
tight seating of the valve plug. It is a pre-loaded
coupling that allows the valve plug to seat
before the actuator reaches its lower limit. The
additional amount of travel compresses the
thrust discs inside the Tight-Seater™, causing a
controlled amount of thrust to hold the valve plug
on its seat when the actuator stem reaches its
lower limit. The Tight-Seater™ is factory-set to
produce a thrust matched to the valve and should
never be disassembled. Control of the amount of
valve stem threaded into the Tight-Seater™ may
be used to adjust the valve seating.
If readjustment of valve seating is necessary,
proceed as follows:
1. With the Handswitch, run the actuator to a
position above the 0% or lower limit position.
2. Loosen the lock nut on the valve stem and
thread the valve stem into the Tight-Seater™.
3. Run the actuator to the 0% position, using a
Demand signal source.
4. Thread the valve stem out of the Tight-Seater™
until the plug seats in the valve.
5. Raise the actuator shaft using the Handswitch
until the plug is clear of the seat and there
is sufficient clearance to make the following
adjustment.
6. Thread the valve stem out of the Tight-Seater™
a fraction of a turn according to the valve stem
thread as listed (1/32" travel):
Thread Turn
3/8-24 3/4
7/16-18 5/8
1/2-20 5/8
3/4-16 1/2
7. Tighten the lock nut and index disc on the valve
stem.
8. Run the actuator to its lower limit using the
Handswitch. The valve stem should stop
before the actuator shaft stops.
9. Reposition the travel index.
CAUTION
If the valve stem is threaded directly
into the actuator shaft without
a Tight-Seater™, the valve stem
should be at least 1/4 turn from
the seated plug position when the
actuator shaft reaches the lower
limit. This will prevent damage to the
valve stem or seat. Do not attempt
to obtain tight shut-off without a
Tight-Seater™ as serious valve
damage may result .
START-UP/OPERATION