Samson 3271-5, Монтаж и эксплуатация

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EB 8310-1 EN 29
Mounting and start-up
5.2.2
Type 3277‑5
Operation with positioner (switchover
plate)
Î
Turn the switchover plate to align the
symbol (A2.4) matching the fail-safe ac-
tion and attachment side with the mark-
ing (A2.5). See Fig. 8.
Operation without positioner (connecting
plate)
Î Turn the connecting plate to align the
symbol (A2.4) matching the fail-safe ac-
tion with the marking (A2.5). See Fig. 8.
Î
Make sure that the gasket for the con-
necting plate is correctly inserted.
Î The connecting plate has threaded holes
with NPT and G threads. Seal the con-
nection that is not used with the rubber
seal and square plug.
5.3 Adapting the travel range
In some cases, the valve and actuator have
different rated travels. Depending on the di-
rection of action, proceed as follows:
Version with fail-safe action "actuator stem
extends" (FA)
When a SAMSON valve is combined with
an oversized actuator (i.e. the rated actuator
travel is larger than rated valve travel), the
bench range is shifted.
Example: DN 25 valve with 7.5 mm rated
travel and 120 cm² actuator with 15 mm rat
-
ed travel; 0.4 to 1.2 bar bench range.
The signal pressure for half of the actuator
travel (7.5 mm) is 0.8 bar. Adding it to the
lower signal pressure range value of 0.4 bar
results in a signal pressure of 1.2 bar re
-
quired for adapting the travel range. The
new lower signal pressure range value is
1.2 bar and the new upper signal pressure
range value 2.0 bar.
Î Write the new signal pressure range of
1.2 to 2.0 bar on the nameplate as the
operating range with adapted travel
range.
Version with fail-safe action "actuator stem
retracts" (FE)
When a SAMSON valve is combined with
an oversized actuator (e.g. the rated travel
of the actuator is larger than the rated travel
of the valve), only the first half of the actua
-
tor's bench range can be used.
Example: DN 25 valve with 7.5 mm rated
travel and 120 cm² actuator with 15 mm rat
-
ed travel; 0.2 to 1 bar bench range.
At half the valve travel, the operating range
is between 0.2 and 0.6 bar.
Î Write the new signal pressure range of
0.2 to 0.6 bar on the nameplate as the
operating range with adapted travel
range.