Samson 3248-1, Mounting And Operating Instructions

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ensure that the plug stem extension (6.3)
with the metal bellows is not twisted.
8. Position clamps of the stem connector (7)
and fasten
9. Align travel indicator scale (5.4) with tip
of the stem connector; for actuators with
"Actuator stem extends" align it with
lower marking (valve closed) and for ac-
tuators with "Actuator stem retracts"
align it with top marking (valve open).
2.1 Option to pretension the
springs for actuator version
"Actuator stem extends"
To achieve a greater thrust, the springs of
actuators can be pretensioned by 12.5 %
(240 cm²), by 25 % (350 and 700 cm²) or
by 75 % (700 cm²) of their travel or their
bench range.
If, with a bench range of 0.2 to 1 bar, the
springs are to be pretensioned by 0.1 bar,
for example, the bench range is shifted by
0.1 bar to 0.3 bar.
When adjusting the valve, a signal pressure
of 0.3 bar is to be set as the lower signal
pressure range.
The new bench range of 0.3 to 1.1 bar must
be marked on the nameplate as bench
range with pretensioned springs.
2.2 Valve and actuator that have
different rated travels
Actuators with springs that have already
been pretensioned by the manufacturer
without attachment to a valve are marked by
an appropriate label.
In addition, such actuators can be identified
by three bolts and nuts protruding from the
bottom diaphragm case which allow the
compression of the springs to be unloaded
evenly before removing the actuator from
the valve.
EB 8093 EN
7
Assembling and adjusting valve and actuator