GE Masoneilan 4700E, Руководство по обслуживанию

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Masoneilan 4700P/E & 4800P/E Positioners Manual =
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Mounting and Orientation
The valve is installed in the pipeline to operate in one of two ways:
Air to Open Air to Close
Close on air failure Open on air failure
(Reverse Action) (Direct Action)
The choice depends on the desired air failure action. This subject is dealt with in separate actu-
ator instructions. The positioner can operate either by direct action (increasing instrument signal
produces an increase in output pressure) or reverse action (increasing instrument signal produc-
es a decrease in output pressure). See Figure 3 and Figure 4.
The 4700E/4800E is not available with reverse action, hence
if the application demands reverse action, a 4700P/4800P
with an external I/P Transducer is required.
NOTE
Installation