Samson 4765 - Range Spring Exchange

EB 8359-1 EN 23
Operating the positioner
the valve starts to move at exactly
1.0bar.
Correct any deviation at the zero adjust-
ment screw (4).
Î Turn it counterclockwise to make the
valve move earlier from its nal position
Î Turn it clockwise to make the valve move
later from its nal position
Upper range value (span) e.g. 0.2bar
3. Once the starting point has been set, in-
crease the input signal to 0.2bar at the
pressure adjuster.
At exactly 0.2bar, the plug stem must
stand still, having moved through 100%
travel (watch the travel indicator at the
valve).
4. If the upper range value is incorrect,
move the pin (2) to correct it. Readjust
1bar and turn the zero adjustment screw
(4) until the pressure gauge indicates the
required signal pressure (see also sec-
tion5.4.2).
If no pressure gauge has been installed,
set the starting point to 0.97bar instead.
6.4 Exchanging the range
spring
If the range is to be altered or changed to
split-range operation, replace the range
spring (Fig.1) as follows:
1. Unscrew screw (7) on the range spring.
Undo hex socket screw (5) and pull out
the lever together with shaft.
2. Exchange range spring. Slide lever with
shaft through sleeve (3), positioner hous-
ing and bracket (6.1).
3. Secure range spring with the screw (7).
4. Move bracket and shaft until the screw
(5) sits on the attened part of the shaft.
Tighten screw (5). Allow for a play of
0.05 to 0.15mm between the lever (1)
and the sleeve (3) as well as between the
range spring (6) and the positioner hous-
ing.