Brooks Instrument 1355 - Manual (Page 19)

3-1
Models 1350E and 1355E
Section 3 Operation Installation and Operation Manual
X-VA-1350E-eng
Part Number: 541B082AAG
August, 2012
3-1 Operation
After the flowmeter has been installed in the flow system, it is ready for
operation. An optional built-in needle control valve may be provided to control
the flow through the flowmeter. These control valves are designed
for fine control. Excessive tightening may damage the valve seat and limit its
effectiveness as a control valve. If tight shut-off is required, it is
recommended that a separate shut-off valve should be installed in the line
immediately before the flowmeter.
Flow indication is measured using the center of the spherical float as the
reference point.