Dresser Masoneilan SVI II AP, Инструкция по эксплуатации

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3 Check Out and Power Up
Overview
This section provides the checkout procedures required to determine if the SVI II AP is in
working order and to power up the unit.
Perform all procedures in this section before putting the SVI II AP into
operation.
Position Sensor Principles
The motion of the control valve (position) is precisely transmitted to the SVI II AP by a pair of
rotating magnets located outside the instrument housing. Rotation of the magnets is sensed
internally by a Hall Effect sensor. Because the only connection through the case is a
magnetic field there are no seals or bearings to wear or corrode.
The rotation of the magnet is linked to the valve position by the mounting hardware provided.
For a rotary control valve the magnet assembly is normally attached directly to the actuator
shaft. For a reciprocating control valve the mounting kit includes the magnet assembly
mounted in a sealed bearing with a lever that must be linked to the valve stem.
The positioner must be installed with the gauges to the left and the housing display and cover
to the right. The ½ NPT conduit entries must be facing down to drain condensate away from
the housing. The positioner can be moved on the valve for best drainage depending on the
position of the valve in the pipeline.
NOTE