Answer / naveed iqbal

actually in proximaty probes inside used PNP tanasistor.so
transistor baising supply need - dc voltage.

Answer / chandrakant sahu

There is PNP type transistor used in ocsilator and also ti keep minimum interference negative voltage is suitable for this

Answer / waleedmahmoud

The basic reason is that the power supply is -24 VDC. So
since the supply voltage is negative the output voltage
will be as well.

IRD at one time made prox probes with a positive supply and
as a result a positive output.

Way back in the 50's uncle Don Bently made a design
decision to use a negative supply voltage (back then it
was -18 VDC rather than -24 VDc in the modern device) in
his circuit. This decision has stuck and is now even
included in the API standards

Positive are also there for example.

Metrix 5465F is -ve gap voltage

Metrix 5465E is +ve gap volatge

It does not make much of a difference wether you use
positive or negetive voltages. It is -ve because Bently
started with the design of -ve and now we stick to -ve.

Answer / md. rizwan

Because we measure the negative voltage in vibration system.

Can be operate control valve without positioning if yes ? how and why?

4 Answers   Focus,

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Yokogawa CENTUMVP R6.09 unable to download to Engineering Station with ExaOPC R3.75 The issue is when I try to download the common project section to the Engineering Station (STN) from the HIS in System View, it is unable to connect. The error displayed is: WARNING: Could not connect to equalize destination. (7001) Retrying. Number of retries = 0/1 ERROR: LdXopsLoadMain: connect error 10060 ERROR: Processing terminated due to connection error. (7002) Equalization end with errors. STN0149 ---- ERROR = 2 WARNING = 1 ---- Background: >Updated the ExaOPC software on the STN from 3.60 to 3.75 >STN operating system is Windows Server 2008 R2 >HIS operating system is Windows Server 2016 Stanard Solutions attempted include: >Ensuring all IP addresses are correct and all networked devices can be pinged. >The ability to ping a device using its host name from another device (<ping STN0149> from HIS) >Ensure both devices firewalls are disabled. >The antivirus installed on the STN is disabled. >Ensuring both devices are within the same workgroup. >Added both devices to each other's Host and LMHost files. >Running IT Security tool after changing any administrative settings.

0 Answers  

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How ejector(or)evactor air pump is working in thermal power plant?

0 Answers  

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why are use only 4 to 20ma. signal.

9 Answers   Otsuka,

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1.In which princeple DP transmeter works? 2.Why UPS system is use for DCS? 3.How drum lvel controller works? 4.What is the difference between glob valve and gate valve? 5.How axial shift probe work & in which princeple it works?

1 Answers   Luberef, Qatar Gas, Reliance,

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What information needs for Control Valve "sizing"

1 Answers   Qatar Petroleums,

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what is function of DCS , and how is it work , explain with difination

1 Answers   Bapco Bahrain Petroleum Company,

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I am a electronics and instrumentation fresher trying for a job in IT sector. what do need to prepare for the interview?

2 Answers  

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My friend has faced this question! I don't know clearly. So please anyone give me the correct and short answer to this question? What is variable frequency drive? Types, what is star to delta? Why this arrangement necessary?

5 Answers   Asian Paints, TCS,

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May I have a brief note above the voltage barriers? Whats is the purpose? Please mail me if you've operational details, mail id: rajkumar.diice@gmail.com

0 Answers  

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which type signal in & out in dcs

4 Answers  

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which one is best profibus or RS485 for communication?

2 Answers   Honeywell,

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