Samson 4785, Монтаж и эксплуатация

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3. Connections
3.1 Pneumatic connections
The air connections are either NPT 1/4 or
G 1/4 tapped holes. The customary fittings
for metal and copper tubes or plastic hoses
can be used.
Note!
The supply air must be dry and free of oil
and dust. The maintenance instructions for
upstream pressure reducing stations must
be adhered to. Carefully purge all air tubes
and hoses before connecting them.
If the positioner is attached directly to the
Type 3277 Actuator, the connection of the
positioner output pressure to the actuator is
fixed. For NAMUR attachment, the signal
pressure can be applied to either the upper
or lower diaphragm chamber of the actua-
tor, depending on the actuator’s fail-safe ac-
tion (either "Actuator stem retracts" or "stem
extends").
Exhaust air:
The exhaust air connection of the positioner
is located on the mounting kit.
For direct attachment of the positioner, a
vent plug is located at the plastic cover of
the actuator. For NAMUR attachment, the
vent plug is to be found at the adapter hous-
ing, and for attachment to rotary actuators,
it is either located at the intermediate piece
or the reversing amplifier.
To guarantee degree of protection IP 65,
the vent plug must be replaced with the filter
check valve included with the device. Also
see "Note!" in section 2 on page 12.
3.1.1 Pressure gauge
To monitor the operation of the positioner,
it is recommended to connect pressure
gauges for supply air and signal pressure
indication to the positioner. These parts are
listed as accessories in Tables 3, 4 or 6.
Fig. 8 ⋅ Mounting the pressure gauge
2...3mm
Throttle with sieve
(order no. 1790-6121)
Nut
26
EB 8382-2 EN
Connections