Emerson Fisher 4320 Instruction Manual page 4

4320 Wireless Position Monitor
Figure 2. Travel Range
should consider when mounting the wireless position
monitor. See the instructions that come with the
mounting kit for detailed information on mounting the
wireless position monitor to a specific actuator
model.
The feedback system for the 4320 wireless position
monitor utilizes a magnetic field for true linkage-less,
non-contacting position measurement. In order to
prevent inadvertent stem movement while the
instrument is in operation, magnetic tools (such as a
magnetic-tipped screwdriver) should not be used.
CAUTION
The magnet material has been
specifically chosen to provide a
long-term stable magnetic field.
However, as with any magnet, care
must be taken when handling the
magnet assembly. Another high
powered magnet placed in close
proximity (less than 25 mm) can cause
permanent damage. Potential sources
of damaging equipment include, but
are not limited to: transformers, DC
motors, stacking magnet arrays, and
magnetic tipped screwdrivers.
As a general rule, do not use less than
50% of the magnet array for full travel
measurement. Performance will
decrease gradually as the array is
increasingly subranged.
4
VALID TRAVEL
RANGE
25 mm (1 INCH)
Y
SHOWN
B
MAGNET
ASSEMBLY
(ATTACHED TO
VALVE STEM)
Note
CURVED ARRAY
ROTARY
NOTE: VALID TRAVEL RANGE
INDICATED BY WHITE ARROWS
Figure 3. Magnet Assemblies
MOUNTING INSERT FACES
GE42127 Rev A
Figure 4. Mounting—Sliding-Stem Magnet Array
The linear magnet arrays have a valid
travel range indicated by arrows
molded into the piece. This means that
the hall sensor (on the back of the
4320 housing) has to remain within
this range throughout the entire valve
travel. See figure 2.
The linear magnet arrays are
symmetrical. Either end may be up.
There are a variety of mounting brackets and kits
that are used to mount the 4320 to different
actuators. However, despite subtle differences in
fasteners, brackets, and connecting linkages, the
procedures for mounting can be categorized as
follows:
D Linear or sliding-stem actuators with up to
4 inch travel
D Rotary actuators with travel up to 90 degrees.
See figure 3 for the different travel feedback magnet
assemblies.
Instruction Manual
Field Trial Release
February 2009
1-INCH ARRAY
2- OR 4-INCH ARRAY