Azbil 100 Series, User Manual

Page: 31 / 80

3-3
3-2. Zero-span adjustment
After Auto-setup, the SVP has calibrated itself to the fully shut (zero) and fully open (span)
values of the valve. If the valve is not achieving the proper relationship between its travel and
the control signal of the SVP, then please adjust Zero-span manually by following the steps
below.
Note) Travel switch will only work if the shut off and full open input signals (Example: 4-20) are
the same as the shut off and full open input signal settings stored or factory set in the SVP.
Procedure for adjusting the shut valve position (zero)
Step Procedure
1
Input current signal that corresponds to the value being fully shut from the
controller (or constant - current supply). (Example: 4 mA)
2
Adjust the valve fully shut position by pushing the travel switch “UP” or
“DOWN”. See Fig. 3-1. and Fig. 3-2. for how to use the travel switch. (If the
forced shutdown function is operating, the valve will not move. To change the
forced shutdown setting, see “4-4-2. Zero/span adjustment”on page 4-9. The
default value is set to 1.0%.)
3
If you changed the forced fully closed with a communicator, change it back to
the proper setting now.
communicator
Fig. 3-1.