Samson 4763, Инструкция по монтажу и эксплуатации

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EB 8359-2 EN 5-9
Installation
5.6 Adjusting the positioner
Intrinsic safety rendered ineffective in
intrinsically safe devices.
Î
Only connect intrinsically safe devices in-
tended for use in intrinsically safe circuits
to certified intrinsically safe input-con
-
nected units.
Î
Do not place intrinsically safe devices
back into operation that were connected
to intrinsically safe input-connected units
without certification.
Î
Do not exceed the maximum permissible
electric values specified in the EC type
examination certificates when intercon
-
necting intrinsically safe electrical equip -
ment (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
).
Î
Connect an ammeter to the control signal
input at the terminals 11 (+) and 12 (–).
Input
control signal
0/4 to 20 mA
Î
Connect the supply air to the supply in-
put (supply 9).
5.6.1 Air output capacity and
proportional band X
P
Fig. 5-9
1. Close the volume restriction (14) as far
as the required positioning speed per-
mits.
Check the positioning speed by pushing
the range spring (6) as far it will go.
2. Adjust the set point at the input to ap-
prox. 50 % of its range. Then turn the ze -
ro adjuster (4) until the valve is at ap-
proximately 50 % valve travel.
On setting the Xp restriction, observe the re-
lationship with the supply pressure as indi-
cated in
Fig. 5-10 . The preset value of Xp
should be approximately 3 %.
3. Check the plug stem's tendency to oscil-
late by pressing the range spring (6)
briefly as far as it will go.
The Xp value is to be adjusted to be as
small as possible, without considerable
overshooting occurring.
Additional points that apply concerning ad -
justment:
Î
Always adjust the Xp restriction before
setting the starting point.
Î
In case of a zero shift (e.g. due to a sub -
sequent change in the restriction setting
or supply pressure), check the zero set -
ting and readjust it.
Î
The adjustment range of the Xp restric-
tion is restricted by the pointer and stop
to one turn (
Fig. 5-10 ). Do not remove
the pointer.
WARNING !