YOKOGAWA Y/11GM, Руководство пользователя

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< Appendix 1. >
A-2
IM 02C01B04-01EN
A1.3 Calibration Procedure using
Calibrating Fixture
This procedure requires a Model 6971 calibrator,
which is available from Yokogawa.
(1) Mount the amplifier on the calibrator with the
flat spring mounting screw to the left. (Be sure
to mount the amplifier in the correct direction.)
Fasten the amplifier with the two wing nuts.
(2) Air supply.
Apply air at 1.4 kgf/cm
2
or bar, 140 kPa, or
20 psi to air supply coupling
2
.
(3) Self-centering the stem valve.
a. Seal nozzle
3
by manual contact for
several seconds, until the nozzle pressure
(diaphragm back-up pressure) is 1.4 kgf/cm
2
or bar, 140 kPa, or 20 psi and confirm that
the nozzle pressure exceeds 1.0 kgf/cm
2
or
bar, 100 kPa, or 15 psi.
b. Open nozzle
3
and manually close the air
check valve, until the nozzle input pressure is
zero (atmospheric pressure).
c. Repeat steps a and b above.
(4) Nozzle input pressure adjustment.
Turn nozzle
3
with a wrench while observing
nozzle input pressure gauge
5
, so the nozzle
input pressure is 0.25 kgf/cm
2
or bar, 25 kPa, or
3.6 psi.
(5) Output pressure confirmation.
Read the output pressure on output pressure
indicator
6
. When output pressure falls
between 0.55 and 0.60 kgf/cm
2
(0.55 and 0.60
bar, 55 and 60 kPa, or 7.8 and 8.5 psi), apply
air pressure at 0 and 1.4 kgf/cm
2
(0 and 1.4 bar,
0 and 140 kPa, or 0 and 20 psi) by one cycle
the same as step (2). Next, confirm that output
pressure falls between 0.55 and 0.60 kgf/cm
2
(0.55 and 0.60 bar, 55 and 60 kPa, or 7.8 and
8.5 psi) under the same condition as step
(4). When the output pressure falls within this
range, output adjustment is completed, but if it
does not, perform output pressure adjustment
as per step (6).
(6) Output pressure adjustment.
a. Close the air supply valve.
b. Remove plug
9
using a 3/16" Allen wrench.
c. Insert a screwdriver in the plug hole and turn
the tension adjustment (turn it clockwise to
decrease output, and counterclockwise to
increase output).
d. Install plug
9
.
e. Repeat steps (2) through (6).
F003.ai
Wrench
Supply air
coupling
Nozzle
Air check
valve
Nozzle input
pressure gauge
Output pressure
gauge
Amplifier
mounting studs
Front view
F004.ai
Plug
Air check
valve
Knob
Supply air
coupling
Rear view
Figure A3. Model 6971 Pneumatic Amplifier
Calibrator
NOTE: The above amplifier output pressure adjustment can
be performed by removing the amplifier from the
calibrator.