Samson 4785, Монтаж и эксплуатация

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3.1.2 Supply air pressure
The required supply pressure depends on
the bench range and the operating direc-
tion (fail-safe action) of the actuator. The
bench range is indicated on the nameplate
as spring range or signal pressure range.
Actuator stem extends:
Required supply pressure = upper bench
range valve + 0.2 bar, at least 1.4 bar
Actuator stem retracts:
The required supply pressure for tight-clos-
ing valves is estimated on the basis of the
maximum signal pressure pst
max
:
pst
max
= F +
d 2
⋅ π ⋅ ∆
p
4
⋅
A
[bar]
d = Seat diameter [cm]
∆ p= Differential pressure across the valve [bar]
A= Actuator area [cm ]
F = Upper bench range value of the actuator [bar]
If there are no specifications, calculate as
follows:
Required supply pressure = upper bench
range value + 1 bar
3.2 Electrical connections
For electrical installation, you are re-
quired to observe the relevant elec-
trotechnical regulations and the acci-
dent prevention regulations that
apply in the country of use.
In Germany, these are the VDE regu-
lations and the accident prevention
regulations of the employers’ lia-
bility insurance.
The following regulations apply for
installation in hazardous areas:
EN 60079-14: 1997; VDE 0165
Part 1/8.98 "Electrical apparatus
for explosive gas atmospheres" and
EN 50281-1-2: VDE 0165
Part 2/11.99 "Electrical apparatus
for use in the presence of combus-
tible dust".
For intrinsically safe electrical equip-
ment approved in accordance with
Directive 79/196/EEC, the data
specified in the certificate of con-
formity apply for the connection of
intrinsically safe circuits.
For intrinsically safe electrical equip-
ment approved in accordance with
Directive 94/9/EC, the data speci-
fied in the EC Type Examination
Certificate apply for the connection
of intrinsically safe circuits.
Caution! The terminal assignment
specified in the certificate must be
adhered to! Switching the assign-
ment of the electrical terminals may
cause the explosion protection to
become ineffective!
EB 8382-2 EN
27
Connections