Samson 4763, Монтаж и эксплуатация

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In the absence of such specifications, pro-
ceed as follows:
Required supply pressure =
Upper bench range value + 1 bar
The positioner output pressure is led to the
top or bottom diaphragm case of the actua-
tor as shown in Figs. 7 to 10.
4 Operation
4.1 Combining positioner and
actuator
The arrangement of the actuator, input sig-
nal, operating direction and mounting loca-
tion is schematically represented in Figs. 7
to 10.
Each subsequent change such as reversal of
the control loop's operating direction or field
reversing the actuator version from direct
"Actuator stem extends" to reverse "Actuator
stem retracts" or vice versa also involves
changing the mounting location of the
positioner.
4.1.1 Determining/reversing the
operating direction
(Figs. 7 to 11)
When the input signal (reference variable w)
increases, the signal pressure p
st
can either
be increasing (direct operating direction <<)
or decreasing (reverse operating direction
<>). The same applies to a decreasing input
signal; the output pressure either decreases
(direct operating direction <<) or increases
(reverse operating direction <>). Symbols
are located on the flapper (10.2) which
identify the respective operating directions
(direct << or reverse <>).
Depending on the flapper position, the ad-
justed operating direction is marked with the
corresponding symbol. If the operating di-
rection of the required function does not
match the symbol or if the operating direc-
tion is to be changed, proceed as follows:
1. Remove both screws of the cover plate,
and lift off the nozzle block (10) along
with the cover plate.
2. Reinstall the nozzle block turned 180° to-
gether with the cover plate, and screw
tight.
Make sure that the nozzle block and flapper
are correctly located above or below the
feeler pin (9.1) as shown in Fig. 11.
If the operating direction is to be changed
after the initially determined arrangement of
positioner and actuator, note that the
positioner must be mounted in a different lo-
cation and the nozzle block must be turned.
Always consider the location of the lever (1)
and the plate (20), "lever on top of plate" or
reversed "plate on top of lever" as shown in
Figs. 7 to 10.
12
EB 8359-2 EN
Operation