Samson TROVIS SAFE 3731-3, Mounting And Operating Instructions

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software or on site at the positioner. A con-
stant air stream to the atmosphere is created
by the flow regulator (9) with a fixed set
point. The air stream is used to purge the in-
side of the housing as well as to optimize
the air capacity booster (7). The i/p con-
verter (6) is supplied with a constant up-
stream pressure by the pressure regulator
(8) to make it independent of the supply
pressure.
All parts are enclosed in an Ex d housing.
The electrical wires are connected over a
separate terminal compartment which is also
designed with Ex d protection.
The extended EXPERTplus diagnostics are in-
tegrated into the positioner. It provides infor-
mation on the positioner and generates di-
agnostic and status messages, which allow
faults to be pinpointed quickly.
The positioner is suitable for the following
types of attachment using the corresponding
accessories:
4 Direct attachment to SAMSON
Type 3277 Actuator: section 4.1
4 Attachment to actuators acc. to
IEC 60534-6 (NAMUR): section 4.2
4 Attachment to Type 3510 Micro-flow
Valve: section 4.3
4 Attachment to rotary actuators acc. to
VDI/VDE 3845: section 4.4
3.1 Application type
Two application types for the valve are
available:
Control valve
and
Open/Close
( on/off) valve . The manual mode
(MAN) and the automatic mode (AUTO)
can be selected with both application types.
Depending on the application type that has
been selected, the positioner behaves differ-
ently in the automatic mode (AUTO)
:
The application type is set in Code 49 - h
(see section 7.7).
After initialization or a reset, the
'Open/close valve' application type is set.
Note:
Depending on the application type,
certain diagnostic functions cannot be per-
formed or analyzed. Refer to EB 8389S on
EXPERTplus valve diagnostics.
EB 8387-3S EN
9
Design and principle of operation
Control valve Open/close valve
AUTO
The positioner fol-
lows the reference
variable continu-
ously.
The valve position
(current position)
appears in % on the
display.
Discrete analysis
of the reference
variable.
The valve position
(current position)
in % and
O/C
(Open/Close) ap-
pear in alternating
sequence on the
display.
MAN
The positioner follows the reference
variable given over local operation.