Boiler emergency e-stop

[JeremyJones]

I think the problem here is terminology, I suspect what your client wants is 2 latching stops, there is a habit to call these E-Stops regardless but it is the circuit that protects it that denotes whether it is or not even if it is inscribed, having said that modern units that comply to E-Stops are defined by colour distinction and sometimes complemented by symbols.
A red actuator against yellow is classed as a E-Stop designation (UK/EU), if I were you after clarifying with the customer I would get a latching stop button that does not meet that colour distinction therefore will not be acknowledge as an E-Stop.
If a genuine E-Stop system is required then it is likely the boiler will not have the correct circuitry to do this, you would have to design and install yourself as a separate system that gives failsafe functionality and interrupts the boilers controls at 2 or more points allowing normal rundown procedures so as not to stop any overrun features of the boiler like fans or pumps that need to ensure safe shutdown.

I will reiterate, we need to understand what the customer is asking and why, what is the full reason for this to be implemented, if there exist no hazards to be averted and it is simply for convenience then latching 'functional stops' are a simple cheap and prefered option that just break the call signal.

Why they are doing this makes no sense. It's a boiler for in floor heat. Incase of an emergency or situation they want to be able to kill power with mushroom head e-stop. At another location we just had 2 single pole switches as "e-stops"

 

[Darkwood]

Why they are doing this makes no sense. It's a boiler for in floor heat. Incase of an emergency or situation they want to be able to kill power with mushroom head e-stop. At another location we just had 2 single pole switches as "e-stops"

This is why you need to have a long in depth discussion with the client, it may be the case it is a zone they want to close off and not the entire system, it may not be a hazard but simple convenience which does not warrant any kind of E-Stop system.

 

[JeremyJones]

This is why you need to have a long in depth discussion with the client, it may be the case it is a zone they want to close off and not the entire system, it may not be a hazard but simple convenience which does not warrant any kind of E-Stop system.

Email I received says "e-stops interlocking with boiler". Ill have a chat with them. If I use single pole switches instead of e-stops I'm sure they will be ok with that

 

[Darkwood]

Email I received says "e-stops interlocking with boiler". Ill have a chat with them. If I use single pole switches instead of e-stops I'm sure they will be ok with that

The lack of info from your client means you are guessing here, they have requested E-Stops, your job is to query they understand the difference here, if it is a E-Stop system they really do need then the design, implementation and liability for it will lie permanently on your shoulders.
If you can establish like I expressed in my recent post that there is simply confusion here based on terminology then it may be a simple job as you suggest but I wouldn't want to be in your shoes if you make a fundamental mistake at this stage and in the near future someone is hurt or property damage occurs.

I hope this all is just a mixup that is causing confusion, I fit E-Stop systems for a living and one of the first things you do is establish what is been requested and how it would be implemented, this is all done at the risk assessment stage. I would also like to mention that if this is indeed a genuine E-Stop system you are installing then are you insured to do this work, my insurance for machinery control and upgrade (which essentially this is if you are installing a E-Stop circuit to a commercial boiler) means my insurance is about 5X higher than a standard installation Electricians, you may need to consult with your insurance company to see if you are covered here, the amount of people I see with basic cover and playing about with machines is gobsmacking in my industry as they never consider they are not covered for the work when asked.

 

[JeremyJones]

The lack of info from your client means you are guessing here, they have requested E-Stops, your job is to query they understand the difference here, if it is a E-Stop system they really do need then the design, implementation and liability for it will lie permanently on your shoulders.
If you can establish like I expressed in my recent post that there is simply confusion here based on terminology then it may be a simple job as you suggest but I wouldn't want to be in your shoes if you make a fundamental mistake at this stage and in the near future someone is hurt or property damage occurs.

I hope this all is just a mixup that is causing confusion, I fit E-Stop systems for a living and one of the first things you do is establish what is been requested and how it would be implemented, this is all done at the risk assessment stage. I would also like to mention that if this is indeed a genuine E-Stop system you are installing then are you insured to do this work, my insurance for machinery control and upgrade (which essentially this is if you are installing a E-Stop circuit to a commercial boiler) means my insurance is about 5X higher than a standard installation Electricians, you may need to consult with your insurance company to see if you are covered here, the amount of people I see with basic cover and playing about with machines is gobsmacking in my industry as they never consider they are not covered for the work when asked.

I really appreciate you're advice, friday I asked for more information based off our discussion and they emailed me what I said above. "E-stops to interlock with boiler for emergency shutdown "

 

[Darkwood]

I really appreciate you're advice, friday I asked for more information based off our discussion and they emailed me what I said above. "E-stops to interlock with boiler for emergency shutdown "

That reply for me does not tell me the client understands the difference between E-Stop and Functional Stop, there is no mention of reasoning here to maybe give us a better idea and like what was mentioned by another member, most boilers will have a shutdown sequence, is that clearly understood by your client, pump circulation, venting fans etc may continue for a preset period IE a controlled shutdown.
I guess you have emailed the client to get that response but if you fail to give all the information and ask the right questions you will get ambiguous answers as such, from that reply I am still no clearer as to what your customer is asking for, the cost difference here could be shy of 1K if we are indeed fitting and integrating a compliant E-Stop system but the category of the system needed will have to be determined by risk assessment and the outcome may simply warrant a small adaption of the boiler controls all the way to an independent safety control board that meets a higher category system.

What confuses me here is what perceived hazards warrant a Emergency Stop system on a standard commercial boiler for heating that it doesn't already have implemented itself, this is why I think your customer may be at crossed purposes and mixing up terminology here.

 

[netblindpaul]

The requirement for an e-stop on the system is down to the integrator, by LAW.
The boiler installation must have been CE marked as an assembly to comply with the LAW.
Forget BS 7671 totally irrelevant.
You are now into EN 60204-1, ISO 13850, ISO 13849-1 & ISO 13849-2.
Then the C-Type standards for boilers.
An emergency stop does not HAVE to shut everything down immediately.
It is written into the LAW and standards such that it can shut things down as quickly as possible in a safe manner.
Examples are cited of exothermic process reactions which may take hours to stop completely in response to an e-etop safety function command.
Other things may have fastest possible deceleration to a standstill under power, with power remaining on to the actuators.
The other thing that MUST be considered is that an e-stop function has a limited life before the components must be changed in accordance with the harmonised standards.
This is taken as a 20 year life, and if the e-stop is going to be used to shut the equipment down at the end of a day then that is 365x20 = 7300 operations in 20 years, the ISO 13849-2 validation needs to reflect that.
This is a minefield that could end up badly if the correct procedures are not followed.
For your own benefit make sure that you are insured to work on boiler controls, and under EN 60204-1 as in the Machinery Directive (UK Supply of Machinery Safety Regulations) and to design and implement safety functions.
You are stepping into an area that most electrical contractors policies do not cover you for.
You could easily end up in prison or bankrupt if things went wrong.

 

[JeremyJones]

That reply for me does not tell me the client understands the difference between E-Stop and Functional Stop, there is no mention of reasoning here to maybe give us a better idea and like what was mentioned by another member, most boilers will have a shutdown sequence, is that clearly understood by your client, pump circulation, venting fans etc may continue for a preset period IE a controlled shutdown.
I guess you have emailed the client to get that response but if you fail to give all the information and ask the right questions you will get ambiguous answers as such, from that reply I am still no clearer as to what your customer is asking for, the cost difference here could be shy of 1K if we are indeed fitting and integrating a compliant E-Stop system but the category of the system needed will have to be determined by risk assessment and the outcome may simply warrant a small adaption of the boiler controls all the way to an independent safety control board that meets a higher category system.

What confuses me here is what perceived hazards warrant a Emergency Stop system on a standard commercial boiler for heating that it doesn't already have implemented itself, this is why I think your customer may be at crossed purposes and mixing up terminology here.

Hahahaha im right there with you on that, it isn't needed.

 

[Timbo]

The requirement for an e-stop on the system is down to the integrator, by LAW.
The boiler installation must have been CE marked as an assembly to comply with the LAW.
Forget BS 7671 totally irrelevant.
You are now into EN 60204-1, ISO 13850, ISO 13849-1 & ISO 13849-2.
Then the C-Type standards for boilers.
An emergency stop does not HAVE to shut everything down immediately.
It is written into the LAW and standards such that it can shut things down as quickly as possible in a safe manner.
Examples are cited of exothermic process reactions which may take hours to stop completely in response to an e-etop safety function command.
Other things may have fastest possible deceleration to a standstill under power, with power remaining on to the actuators.
The other thing that MUST be considered is that an e-stop function has a limited life before the components must be changed in accordance with the harmonised standards.
This is taken as a 20 year life, and if the e-stop is going to be used to shut the equipment down at the end of a day then that is 365x20 = 7300 operations in 20 years, the ISO 13849-2 validation needs to reflect that.
This is a minefield that could end up badly if the correct procedures are not followed.
For your own benefit make sure that you are insured to work on boiler controls, and under EN 60204-1 as in the Machinery Directive (UK Supply of Machinery Safety Regulations) and to design and implement safety functions.
You are stepping into an area that most electrical contractors policies do not cover you for.
You could easily end up in prison or bankrupt if things went wrong.

I re-iterate the OP is in the USA.
CE markings and BS, EN, standards therefore don't mean a thing.

 

[plugsandsparks]

Boilers no matter country you are in need to be shut down correctly according to the MI's.

I suggest OP forwards the email request from client to the boiler tech support team and ask them how best to "shut down in case of emergency" - AKA, lazy mans way of turning off at night, lol

 

[Spoon]

I re-iterate the OP is in the USA.
CE markings and BS, EN, standards therefore don't mean a thing.

The USA have their own standards that they have to work to, so the principle still applies.

 

[Darkwood]

As an overview here to simplify it a bit, you have to treat an E-Stop actuator like a normal stop button, on it's own it is not an E-Stop even it it complies with the standards by design, it is only an E-Stop when part of an E-Stop system that meets relevant standards.
It is like sticking a Lamborghini badge on a Fiesta, the badge does not change the car to a Lamborghini and on its own the badge is not a Lamborghini even if it is made for one, the same applies to the various stop actuators that comply to be used as E-Stops.

 

[JeremyJones]

As an overview here to simplify it a bit, you have to treat an E-Stop actuator like a normal stop button, on it's own it is not an E-Stop even it it complies with the standards by design, it is only an E-Stop when part of an E-Stop system that meets relevant standards.
It is like sticking a Lamborghini badge on a Fiesta, the badge does not change the car to a Lamborghini and on its own the badge is not a Lamborghini even if it is made for one, the same applies the various stop actuators that comply to be used as E-Stops.

I think you're right about that. They are using the word e-stop wrong. They just want something to kill power to the boiler if there's an emergency or issue

 

[netblindpaul]

I re-iterate the OP is in the USA.
CE markings and BS, EN, standards therefore don't mean a thing.

I didn't see that stated anywhere. ?‍
The USA are catching up with the ISO & IEC standards requirements as they are members of both organisations.
They are just a bit slower than the rest of the world because of the difference in the way they blame people and mandate PPE rather than addressing the real hazards.
Also their equipment design is about 20 years behind the world that has embraced the IEC standards, having assessed both, the US equipment is positively dange in comparison to equipment to base IEC requirements.
Almost all BS & EN standards are derived from ISO & IEC source document, some are identical, and if North America was not so stuck in its ways and arrogant about their so called supremacy, they would accept the standards they had a hand in writing, and save millions in currency and massive global resources.
Plus some of the documents I have quoted are ISO standards so the USA are bound to implement them in the same way the UK has to implement IEC 60364.
The control philosophy in the US is aligning and the intent is similar.

 

[Lister1987]

I didn't see that stated anywhere. ?‍
The USA are catching up with the ISO & IEC standards requirements as they are members of both organisations.
They are just a bit slower than the rest of the world because of the difference in the way they blame people and mandate PPE rather than addressing the real hazards.
Also their equipment design is about 20 years behind the world that has embraced the IEC standards, having assessed both, the US equipment is positively dange in comparison to equipment to base IEC requirements.
Almost all BS & EN standards are derived from ISO & IEC source document, some are identical, and if North America was not so stuck in its ways and arrogant about their so called supremacy, they would accept the standards they had a hand in writing, and save millions in currency and massive global resources.
Plus some of the documents I have quoted are ISO standards so the USA are bound to implement them in the same way the UK has to implement IEC 60364.
The control philosophy in the US is aligning and the intent is similar.

They do have NFPA 79 which would be their regional variant of the ISO standard