Samson TROVIS 3730-1, Перевод оригинальной инструкции

Страница: 68 / 144

5-34 EB 8484-1 EN
Installation
5.7.4 Supply pressure
The required supply air pressure depends on
the bench range and the actuator's direction
of action (fail-safe action).
The bench range is written on the nameplate
either as the bench range or signal pressure
range depending on the actuator. The direc-
tion of action is marked FA or FE or by a sym-
bol.
Actuator stem extends FA (AIR TO OPEN)
Fail-close (for globe and angle valves):
Î
Required supply pressure = Upper bench
range value + 0.2 bar, at least 1.4 bar.
Actuator stem retracts FE (AIR TO CLOSE)
Fail-open (for globe and angle valves):
For tight-closing valves, the maximum signal
pressure pst
max
is roughly estimated as fol-
lows:
pst
max
= F +
d² · π · ∆p
[bar]
4 · A
d = Seat diameter [cm]
∆p = Differential pressure across the
valve [bar]
A = Actuator area [cm²]
F = Upper bench range value of the
actuator [bar]
If there are no specifications, calculate as
follows:
Î
Required supply pressure = Upper bench
range value + 1 bar
5.8 Electrical connections
Risk of fatal injury due to the formation of
an explosive atmosphere.
Î
For installation in hazardous areas, ob -
serve the relevant standards that apply in
the country of use.
Standard applicable in Germany:
EN 60079-14 (VDE 0165, Part 1)
Explo-
sive Atmospheres – Electrical Installations
Design, Selection and Erection.
Sudden loud noise when the pneumatic
actuator vents.
Î
Wear hearing protection when working
near the valve.
Incorrect electrical connection will render
the explosion protection unsafe.
Î
Adhere to the terminal assignment.
Î
Do not undo the enameled screws.
Î
Do not exceed the maximum permissible
values specified in the EC type examina
-
tion certificates when interconnecting in -
trinsically safe electrical equipment (U
i
or
U
0
, l
i
or I
0
, P
i
or P
0
, C
i
or C
0
and L
i
or L
0
).
Selecting cables and wires
Î
Observe the relevant clauses of
EN 60079-14 for installation of intrinsi -
cally safe circuits.
DANGER !
WARNING !
WARNING !