Answer / satishkumar

first, check the SOV coil is working or not and then check
the power supply from DCS to sov coil.

Answer / raffi

Signal(Soft PB) for SOV to open in Manual and Auto are same (DO)
While your are running in AUTO. it is working with interlock/logic i.e feedback from other IOs

While in Manual mode you should press the SOV button to open after change the mode to manual

If it not working in AUTO then Check the malfunction of feedback signal IO card or carryout the loop checking for feedback signal to sort out the issue

Answer / fellyc

Assume that both Manual Command (PB) and Auto signal comes
from the DCS ( Same DO).
If it works in Mamual Mode and not in Auto Mode, then check
the logic for an interlock or permissive.

Answer / ganapathi s.b

First check DO out put came or not. if signal not come check Do module, if signal came then check sov coil Resistance value
either open or short.this is main problem of not working in Auto mode.

Answer / raja

Need to be check the DCS I/O cart the DI cart digital output cart some time give fault signel the I/O cart malfunction

Answer / sriram

Either manual mode u operate from dcs then the DO card is good. so check the interlock

Answer / hansdas b.jaiswal

If you are operate solenoid valve with out load so please
connected it a power cylinder or actuator some time
solenoid valve not works in auto mode with out load.

Answer / govarthan

whether card is not working sov not working in man mode also i think ter s an external interlock check it..

can u briefly explain aboutan aryton shunt multirange DC ammeter?

0 Answers  

a flow transmitter [range-0-400mbar] connected in process line. please explain me how to calibrate the flow transmitter , & how to do static error

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Hi Friends i am going to write BARC written test by this month 20th (20-5-2008). So please if any body knows the details about this or having previous question papers pls mail me to kkumarei@gmail.com. For Suggestions give one message to 9962122264

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give classification of transducer based on type of application

2 Answers  

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what is interlock system and why we use of this?

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how to convert digital signal to analog signal in plc

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please send me hpcl placement papers

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how to convert bar to mA?

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what is shutoff dp? why is it important for selection of a control valve?

1 Answers