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Instruction Manual
June 2010
Table 12. Split-Range Capabilities
3582 POSITIONERS
0.2 to 1.0 Bar or 3 to 15
Psig Input Signal
Split
Bar
0.2 to 0.6
Two-way
0.6 to 1.0
0.2 to 0.5
Three-way
0.5 to 0.7
0.7 to 1.0
11 to 15
3582i POSITIONER
Split
4-20 Milliampere Input Signal
Two-way
Three-way
The flapper must approach the nozzle
squarely at the midpoint value of the
input signal range for proper
operation.
On some applications where the input
signal span is comparatively small (as
found with split-range applications),
the nozzle adjustment may not be
enough to set the proper starting
point. Also, some difficulty may be
experienced in keeping a valve
positioner from unloading when the
input signal continues to increase
above the split-range.
For example, for a 0.2 to 0.6 bar (3 to 9
psig) input signal range, the input
signal could increase to 1.0 bar (15
psig). Continued bellows travel due to
the increased input signal over the
split-range would drive the flapper into
the nozzle. The impact could possibly
cause misalignment between the
flapper and nozzle. Such a
misalignment, in turn, could affect
split-range calibration.
In these cases, adjust the follower
assembly screw in addition to the
nozzle adjustment to obtain
satisfactory results.
0.4 to 2.0 Bar or 6 to 30
Psig Input Signal
Psig
Bar
Psig
3 to 9
0.4 to 1.2
6 to 18
9 to 15
1.2 to 2.0
18 to 30
3 to 7
0.4 to 0.9
6 to 14
7 to 11
0.9 to 1.5
14 to 22
1.5 to 2.0
22 to 30
4 to 12
12 to 20
4 to 9.3
9.3 to 14.7
14.7 to 20
Note
3582, 582i, and 3583
3582 valve positioners require a
relatively small percentage of the
instrument pressure span to obtain full
valve travel. With the travel pin set to
equal the valve travel, the input signal
change required to fully stroke the
valve can be reduced to 33 percent of
normal input signal change. With the
travel pin set to a value greater than
the valve travel, the input signal
change required to fully stroke the
valve can be reduced to a minimum of
20 percent of normal input signal
change.
Changing Valve Positioner Action
Converting a 3582 valve positioner or 3582i valve
positioner from direct acting (an increasing input
signal, either pneumatic or electrical, increases
output pressure) to reverse acting (increasing input
signal decreases output pressure) or vice versa
requires no additional parts. The position of the
flapper assembly on the beam determines the
action. As shown in figure 15, the beam is divided
into quadrants. The direct-acting quadrant of the
beam is labeled DIRECT and the reverse-acting
quadrant is labeled REVERSE. To change the
positioner action, simply move the flapper assembly
to the opposite quadrant of the beam. Perform the
calibration procedures in the valve positioner
calibration section.
Changing Valve Stem Position
Transmitter Action
Refer to figure 20 for key number locations unless
otherwise indicated.
The flapper of the 3583 valve stem position
transmitter is always positioned in the reverse-acting
quadrant as shown in figure 19. To reverse the
signal, reverse the cam as follows:
1. Unhook the spring (key 38), and remove the cam
bolt (key 6), cam (key 4), and spring retainer bracket
(key 43).
2. Screw the locking nut (key 45) all the way onto
the cam bolt.
Note
23
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