We are not electricians but buy the gear for our subcontractor to fit on a labour only basis. Our electrical subcontractor is not 100% sure what is required except for a relay or contactor. We have spoke with the 2 wholesalers we use and they are not sure either. We have a woodworking machine shop with 7no 3ph machines all with different amp ratings and a 3ph dust extractor. We require the dust extractor to start up on powering up any of the machines as our lads are not following h&s procedure. We could have more that one machine going at once and would require it on till the last machine has stopped. Any help appreciated.
Advise on automatic machine power up
- Thread starter WMP
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WMP,
First, welcome to the forum.
This is do-able, but, it takes quite a lot of thought, and it opens a whole new can of worms that you have not thought about, and I don't believe you want to think about!
It is not an easy solution to make and be compliant with statute law, the way you have worded your post it seems that you are running a business?
Thus you are covered by HASAWA, PUWER, & MHSWR etc.
Thus, to comply with the requirements of these, and your business insurer you need to make sure such modifications to machinery and systems are compliant with statute law requirements.
Simplistically you need all your machines wired in parallel to start the LEV, however, it is the implementation of this that gets tricky to comply with as you are linking all the machines together and to the LEV. I was at a customer of mine the other week, and their electrician had tried this and failed dangerously.
The issue you have is that you are aware of the scenario, and are looking to do something, engineering controls are above discipline and procedure in the hierarchy of control, so you must exhaust all engineering possibilities before you move down to procedure and discipline.
Cost wise, you are going to be a bit stuck, as it sounds like you have a lot of machines, and thus lots of employees, and thus the potential of harm to lots of people simultaneously, thus you will need to spend lots of money on engineering controls before you can justify moving to discipline and procedure.
Also the whole thing will need to be CE marked, and compliant with the relevant standards and statute regulations.
Yes it is possible and doable, but, not by giving snippets over the forum i don't believe, sorry.
I know what is involved in doing things like this to comply with the law as it is a major part of my business.
I'm not trying to put you off, the opposite, I am trying to help you spend your money on getting the job done correctly and in a compliant manner.
Emergency stop systems on any machinery for example MUST meet PLc as a minimum to be compliant with all statute law requirements as this is written into the standards, unless you can prove what you have done offers an equivalent level of safety.
Please ask more, but, also, please do not be tempted to just do something that works, as I've seen this go badly wrong, and before anyone asks, yes linking machinery by even one signal, does make it a linked machine in the eyes of the law.
This is documented in Ian Fraser's guide.
First, welcome to the forum.
This is do-able, but, it takes quite a lot of thought, and it opens a whole new can of worms that you have not thought about, and I don't believe you want to think about!
It is not an easy solution to make and be compliant with statute law, the way you have worded your post it seems that you are running a business?
Thus you are covered by HASAWA, PUWER, & MHSWR etc.
Thus, to comply with the requirements of these, and your business insurer you need to make sure such modifications to machinery and systems are compliant with statute law requirements.
Simplistically you need all your machines wired in parallel to start the LEV, however, it is the implementation of this that gets tricky to comply with as you are linking all the machines together and to the LEV. I was at a customer of mine the other week, and their electrician had tried this and failed dangerously.
The issue you have is that you are aware of the scenario, and are looking to do something, engineering controls are above discipline and procedure in the hierarchy of control, so you must exhaust all engineering possibilities before you move down to procedure and discipline.
Cost wise, you are going to be a bit stuck, as it sounds like you have a lot of machines, and thus lots of employees, and thus the potential of harm to lots of people simultaneously, thus you will need to spend lots of money on engineering controls before you can justify moving to discipline and procedure.
Also the whole thing will need to be CE marked, and compliant with the relevant standards and statute regulations.
Yes it is possible and doable, but, not by giving snippets over the forum i don't believe, sorry.
I know what is involved in doing things like this to comply with the law as it is a major part of my business.
I'm not trying to put you off, the opposite, I am trying to help you spend your money on getting the job done correctly and in a compliant manner.
Emergency stop systems on any machinery for example MUST meet PLc as a minimum to be compliant with all statute law requirements as this is written into the standards, unless you can prove what you have done offers an equivalent level of safety.
Please ask more, but, also, please do not be tempted to just do something that works, as I've seen this go badly wrong, and before anyone asks, yes linking machinery by even one signal, does make it a linked machine in the eyes of the law.
This is documented in Ian Fraser's guide.
I've done something similar with emergency lights. It would take 7 relays coils looped through each other and when ever one is activated all are on and it would bring on the coil to the extraction contactor.
Yes Rap it might but, there are other ways, however it must be designed and validated to comply with statute law unless the company wants to knowingly commit a criminal offence.
The UK SMSR requires linked machines to be CE marked as an assembly.
This modification would constitute linking.
The UK SMSR requires linked machines to be CE marked as an assembly.
This modification would constitute linking.
Thank you for your advise. I will have to find an electrical engineer to design the system as our subcontract electrician is not 100% on how to make it work. With my little knowledge of electrics I thought it maybe possible to take a switch live back from each machine from the same phase to a relay or contactor.
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By assessing it under the relevant standards & regulations curing any deficiencies identified and putting a technical file together, unless an NB is needed, then you get them to do it.
Don't forget that any safety systems must be designed and validated to EN 13849-1 & -2 or EN 62061.
So, you need the Engineer to be familiar with that too, as depending on the layout and design, you may need emergency stop systems to be incorporated.
Don't forget that any safety systems must be designed and validated to EN 13849-1 & -2 or EN 62061.
So, you need the Engineer to be familiar with that too, as depending on the layout and design, you may need emergency stop systems to be incorporated.
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user 28595
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As an alternative, would having the machines disabled until the extractor is switched on work?
cheers, Paul
cheers, Paul
Still linked machines.
Doesn't have to be an electrical link.
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This cunning plan is probably flawed in 1001 ways and it is literally decades since I did any machine tool controls but
first bloke in work in morning switches extract on, last bloke out at night switches extract system off?
just saying
first bloke in work in morning switches extract on, last bloke out at night switches extract system off?
just saying
thats too simple
the whole thread shows just how thick / stupid people are. owner need a way to make sure the machines cant be used unless the extract is on because the staff are too thick to turn it on first or just dont notice that it isnt on but continue anyway
the whole thread shows just how thick / stupid people are. owner need a way to make sure the machines cant be used unless the extract is on because the staff are too thick to turn it on first or just dont notice that it isnt on but continue anyway
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This thread also shows how a simple solution is impossible as the people who make the rules are too clever to allow anyone to do a proper job without them telling you how.
It's all just OTT, stick a contactor in and link it to each machine and be done with it.
It's all just OTT, stick a contactor in and link it to each machine and be done with it.
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That would be good, but who wants to run a 30kW motor all day when perhaps for 60+% of the day it is unused.
Plus, the noise levels generated by the LEV, may well be above the action level, which requires engineering controls as a first measure to reduce them, so simple answer to reduce the noise is turn it off, and that is the first thing on the hierarchy of controls to protect the workers, so, you are then back to square 1.
The trouble is Lurch, you get people getting involved who can't do it correctly.
This then results in people getting hurt, which results in rules getting made, the issue are the people who "think" that they can do it safely, but can't these then cause issues that result in regulations, and these are then law, so like it or not they must be complied with.
Don't forget, if you do something like this and it's not compliant with the law, and someone gets hurt, or worse killed, you can't insure against that.
Remember, an electrical designer was recently jailed because his safety system was not safe, and it resulted in a man being baked alive.
What makes this story so sad is it was one of the relatives of the deceased that initiated the process that killed him.
A simple solution is possible, one just has to do it right.
Don't forget machinery is "policed" by HSE, and they have a permanent warrant, that is they can enter a workplace at any time, without the requirement of a warrant from a judge, so in that aspect they have more powers then the Police.
When it goes wrong, and they sit you down in the room, the first thing that they will do, Police present or not is put you under legal caution, you know, the old "anything you say" job.
If you are putting yourself in a place where you say that you can do things like this, then you had better be able to justify that, and have the information, qualifications, experience, training and competence to back it up.
Remember also, these rules are to keep dangerous machinery out of the country, and ensure that companies in the UK can compete with others around the World who are subjected to the same rules.
This is not a global thing unfortunately though!
Canoeboy said:
That's a passive link, and you know it, it is only an active link that is an issue, and you know that too!
Any sensor of any type that sends a signal between two discrete pieces of equipment no matter which one it is "supplied from", or which one it "controls" results in them being linked.
The ducting does not send signals.
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Well, you could argue that the air flow is signalled at the machine end, not much different to the hall effect transducers I mentioned earlier, if you wanted to interpret the rules that way, which you probably could, like all of the vague rules we have to comply with.
The thing is Lurch this time it's not a vague rule, it's written into statute law, and the regulations, standards & guidance.
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