Answer Posted / r.murugan
IF ITS PNEUMATIC CONTROL VALVE FIRST WE HAVE TO CHECK
INSTRUMENT AIR PRESSURE THEN WE HAVE TO REGULATE THE
INSTRUMENT AIR PRESSURE REGULATOR TO I/P COVERTER AND
PNEUMATIC POSITIONER
BEFORE STROKING THE VALVE WE HAVE TO CHECK VALVE AT NEUTRAL
POSITION IF NEUTRAL POSITION THEN ONLY CAN MOVE THE THE
VALVE
IF AIR TO OPEN VALVE WHEN COMMAND 4ma VALVE POSITION SHOULD
BE CLOSE (DIRECT OPERATION) LOCAL WE HAVE TO MECHANICAL
SCALE CLOSE INDICATION
THEN INCREASE THE CURRENT 4.5ma TO 5ma to check the start
of opening the control valve
then gradually can increase and decrese the current and
corrospondingly check the stroke momemnt based on command
we have to check the feedback
| Is This Answer Correct ? | 16 Yes | 7 No |
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