Remote Manual ESD Station

Define EDS station.

I understand it as electristatic discharge.

Please, announce the location of the station if it has anything to do with explosive environments, as I will want to stay way far away from it.

You need to hire someone who can guide you.

We cannot, because we have no idea what you are trying to do.

I mean by ESD station pushbutton used to cause emergency shutdown when it pressed manually by operator if he see any hazard situation like fire

Then, IT IS IMPREATIVE THAT YOU HIRE a QUALIFIED consultant to do this, or the likelyhood of killing people with an unsafe installation is very high.

Your asking total starngers who have no idea of the location, installation, nor legal or code implications indicates a total lack of regard for human life on your part.

It will be difficult to see a fire from 8 Km away.

Don't be so cheap, hire a safety officer! Please don't tell us you ARE the safety officer!!!!!!!!

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I am not the safety officer

off course i will refer to the vendor of the safety system .

the operator will have alarms which will be transfered to him in this area and not only fire may cause the operator to make ESD , all I am asking about is the possibility to do this with that long distance

You may well refer to the vendor's safety system. But they will not design and spec. the safety circuitry and equipment. Unless you pay them to come to site and do so, they'd be exposing themselves up to all sort of possibilities of litigation otherwise. So in essesence you'll be hiring a safety consultant, as mentioned in other posts. Otherwise your company will have to risk assess all the possible hazards your trying to protect yourself, staff and equipment from. From that risk assessment you'll identify the category of safety circuitry required for the type of hazard. That's the easy part, now comes the difficult part of designing and implementing a safe, practical and efficient safety system.

some thing like the photo below . what I meant is normal ESD pushbutton connected to the Safety system , but to Analog channel to allow monitoring using serial and parallel resistance

Automatic fire detection systems can be used to initiate emergency shutdown.

What is more alarming is the concept that a fire at the remote location could actually occur. Is this thread actually a cloak for a different problem - one that involves process materials containment issues, housekeeping issues, or the absence of an inherent safety philosophy on process design?

The focus needs to shift further upstream to deal with the cause, and not the effect.

The OP states:-

'I mean by ESD station pushbutton used to cause emergency shutdown when it pressed manually by operator if he see any hazard situation like fire'

To me this sounds as if FIRE isn't the only hazard. The OP question is so vague (as seems to be the norm these days), that it gives you the impression that the OP doesn't truely know exactly what he wants. Or doesn't have a full appreciation of what's required.

Very DANGEROUS combination.

Quite.

Why should the system only shut down when the operative sees fire and is able to press a button <rhetorical question - NNTR>? What if no-one is watching?

• The simplest automatic fire shutdown system is a spring-loaded switch maintained in the on position with a piece of sisal string. When a fire takes place, the string burns through, snaps, and the spring turns the switch to the off position. Why does one need an operative at all?

If the original poster would only state the nearest town to the installation, CR4 readers could avoid it in their travels.

Now you might be getting to the point where the OP's grey matter might be getting stimulated. Now wouldn't that be a revalation.

Watch this space....

If the required shutdown is purely for FIRE, why hasn't the remote site got it's own FIRE suppression system in place. This localized FIRE suppression system should take care of the the shutdown process.

Unbelievable, isn't it?

I too thought ElectroStatic Discharge when I read your acronym.

Given the context you slightly described, I was betting that ESD had the same meaning as E-Stop.

Emergency ShutDown I dig it.

Remote E-stops are nothing odd and easy enough to establish.

I'll read your OP again and try to figure out what's bothering you about your requirement.

Feel free to add some supplementary info in case I am a slow reader....

You may need something like radio control, or a cell phone (with suitable app) at the business end of this scheme. Or if there is power wiring over this distance, there are ways to multiplex control signals on it.

From what you've implied but not stated, I can safely tell you that your wish for an Emergency Shut Down push button can be fulfilled. Remote controls are a simple matter now. Because you had to ask a public forum this rudimentary question I highly recommend that you hire a reputable engineering firm to advise you how to install a proper push button and the large amount of ancillary equipment it will take to know if the button should be pushed. You have already demonstrated you do not possess the sensibility to evaluate the flavors of a jelly bean. You need outside help. Any system dangerous enough to require an emergency shut down system that is 8 kilometers away must be designed by intelligent, responsible individuals with a firm grasp of the risks and how to properly mitigate them.

Now go somewhere else for your homework assignment.

One solution I can suggest is to install and wire Emergency Push Button to Slave Digital I/O module local to ESD, use remote PLC. Select PLC and Slave I/O module having Ethernet communication port. Link two via Ethernet cable.

Slave Digital I/O can be used for other inputs also to PLC or Master Station.

The Firm hired to supply Hardware, software, logic/program and commissioning shall provide necessary required detailed expertise.

Ramesh

8,000 meters of Ethernet cable is a really good trick. The standard specification has a maximum run of 100 meters.

The use of remote I/O the best solution for this problem, but it should be linked to the master using optical fiber. Typical transmit distance for single-mode is 20 km.

An Emergency Shutdown Stations (aka Emergency Shutdown Pushbutton) can be placed most anywhere that HAZOP or PHA / Risk Analysis defines it.

My own appreciation is that placing it 8 km from the plant maybe a problem, since whomever has to actuate may not have any clear information as to how or why to do it, generally you want it far enough from the plant area so that someone running out of it can trip it, but not so far they have to radio or drive to the Pushbutton.

Having said that it is the HAZOP, PHA or other Risk Analysis Study that; a) defines the need, b) defines the actuation requirement, c) how many pushbuttons may be needed and d) defines where it has to be located.

As to having the ESD monitored on an analog channel may not be the best or wisest since you need to read one single pulse or change of state.

Generally the ESD is connected to a dedicated ESD system.

Having said, comes the following recommendations:

1.- HIRE an engineering team to perform risk analysis, HAZOP or PHA as needed to define what is needed to perform the ESD function correctly.

2.- HIRE the engineering team to define correctly what you need, how many you need, where they have to be located and finally to define how the ESD system has to actuate to perform a safe and controlled plant shutdown.

A big issue you have with this is the cable length involved. A cable of this length can act as a sizeable capacitor which easily screw up the iput to your ESD system.

To re-iterate what the others have said yes this is not straight forward and yes it does need expert help.

At 8 kilometers of cable length there will be transmission line concerns. This will induce reflections and ringing effect much more than just a simple lumped element capacitance.

now you understand my concerns thank you all for your answers it was helpful and sorry if the subject seems not clear or rudimentary like redfred said but please not that the forums is not for expert only especially instrumentation is like an ocean if you are good in one field you may not be good in other.

thanks all

8Km seems a bit far, unless someone has deemed it the outer fringes of the blast zone. That being the case, then by the time the blast has reached the outer marker, there will be no need for a ESD.

I would suggest that you first look at who would operate the ESD and why? Then decide from where!

Comments have been good, but I suggest you regroup and decide on exactly where you are going to place this ESD, if at all it's needed so far away!

Are you trying to tell us that this remote site isn't manned?

hi,

thank you very much for your concern and reply to my question it seems that I was not clear from the begining sorry for that.

if your interested to know the issue in details below my description

In our application the process facilities is distributed in two far areas about 8 km far each belongs to different companies ; the first area contains beside the process facilities the integrated control and safety system (ICSS) and the other contains beside the process facilities detected PLC .

The problem comes from the requirement of the second area company to have manual intervention to shutdown the first area in case of emergency.

And as the solution of radio link between the two systems was excluded, I proposed to have hardwired manual ESD pushbutton.

Taking into consideration that the ESD pushbutton shall be connected to analog input channel in order to be monitored using serial and parallel resistances , the required length could affect not only on the size of the cable to eliminate the voltage droop but also it may have transmission line concerns like capacitance , reflections and ringing effect.

after replies to my thread now the question is it applicable to connect the Pushbutton conventionally and can eliminate these effects or by other way? How we install it? Or it is not applicable at all and we have to think again about it?

thanks and best regards

Thanks for sharing the additional information.

This is a telemetry transmission exercise at that sort of distance.

Why is the use of radio for transmission excluded?

What is the conventional way that you speak of?

Please tell us more about what needs to be stopped before it sets off for/reaches the distant end. Can't this feature be at the point of entry of the distant receiving end?

You could just make a telephone call and yell "STOP"!

Yes, this is a telemetry transmission exercise in more ways than just understanding Oliver Heaviside's Telegrapher's equations. Unless the entire 8 kilometers of signal path is owned by the two parties, the right of way for any cable must be secured. Then there's the problem of protecting this cable from damage by man, machine and critter. Don't forget that since this is an emergency signal, any failure in communication must be detected. I almost forgot, weather effects of water and certainly lightning must be considered. Then there's the probable complication of a ground loop creating interference.

Hire a consultant.

I'm glad somebody has started to talk about maintaining the safety integrity of this safety circuit.

I'm at a loss to understand why anybody would expose themselves to the possibility of a plant shutdown, due to a false trigger of this safety circuit, which is exposed over it's 8Km length to all the possible causes of damage you've mentioned above, to this safety circuit.

Time for a risk assessment again.