GE Masoneilan 4700E, Maintenance Manual

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When installing a positioner on a valve, it is necessary to
choose the proper valve action and positioner action. It is
absolutely necessary to place valve travel at the point
corresponding to the low end of the signal range when
removing or installing a cam. At this point, feedback spring
compression is at lowest value and will facilitate cam
removal or installation. Prior to performing any work, read
and understand “General Description and Operation” on
page 15 and “Mounting and Orientation” on page 19. Define
the scope of work to be performed and find the appropriate
section that should be followed.
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The 4700 series positioners have the same mounting and link-age attachment dimensions as
the 4600, 4600A, 4600B and 4700B series positioners but have a different layout of pneumatic
connections. They can replace the older models if operational requirements are identical and
pneumatic connections are changed. The mounting details in this instruction cover only the
more widely used valves and actuators.
Cover Removal
The snap-on cover must be removed to access the zero and span adjustments and to mount the
positioner on the valve.
To remove the cover (Figure 2), press the latch bar inward as shown in the figure below, pull cover
away from body until latch tab is clear, then pull along body axis to free the two top locking tabs.
Figure 2 Cover Removal
CAUTION