Circuit design justification.

bill4807

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Mar 2013
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michigan
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Hi all,

This will be long, I apologize for the length. I feel like I am in between a rock and a hard place. And would like some help or direction. To also help with my education as well. I am struggling with justifying circuit design and the cost, time associated with it to owners/managers/ non-controls folks after the risk assessment is complete. Now before everybody goes off on me here, let me say that If we do any turnkey or robot jobs this is in my control and it is properly done and designed to accomadate the appropriate safety level.
Now for the situation, on occasion we import machinery from korea/japan/italy, germany,switzerland ect, ect. For the most part the italian and german machinery come prepared and mostly meet applicable standards. But the other machinery i would consider being equivelant to a "Category B-1" controls architecture. " speaking in terms of categories" I can elaborate more if needed but ...with that being said, Customer buys the machine, this customer has no controls dept. With no standards. Me and others complete the risk assessment, Clearly it should meet category 3. In ANSI, NFPA79, and NEC it states Risk assessment to be done. But other documents also point out that it's the end user in combination with the OEM to come up with the conclusion.
So the question that arises to me is "how is it now that after 15 years of selling these this way should another $4500-6500 be spent in labor and material." Let me say these are brand new machines so wiring needs to be out and new in as well as hardware..
Anyone can lead me in the right direction?
Am I right for continually bringing this up?
It is driving me crazy as to, is it interpretation? Side note: I do not own the company.

Thanks for any responses that come
 
Just because you did it a certain way for 15 years does not mean that you should not change with new information. A perfect example is the auto industry. There used to be no seatbelts in any of the cars and now they are there in every car.

Any time you start applying risk assessments, the cost will go up. It costs money to do all the checks to certify that a piece of equipment was safe. At one of my previous employers, we started having our vendors provide us with their risk assessment. This helped us streamline the process and hold our vendors accountable with providing us with a verified safe system.

This also becomes something that you can sell. To the customer, you can say that risk assessments have been done and if they want to have copies of the documents, you can sell them. I have seen this go for $750 and up.

If you are having to take a brand new machine and then gut it and rebuild it to make it safe, you need to hold the vendor accountable or find a different vendor.

Another benefit of having done the risk assessments is that if something does happen, you have documented that you did everything to minimize risk and the judgements tend to be less in court.

Do not shortcut safety.
 
it doesn't matter where you buy the equipment or what country, if you sell it, YOU are responsible for it and all aspects of safety.

who ever you buy the equipment from, you need to provide them ALL the specs for safety, wiring requirements, and risk assessments.

yes, the price may go up and probably will, and your price to the customer will go up also, but you have a paper trail showing due diligence to make it right if something happens.

james.
 
it doesn't matter where you buy the equipment or what country, if you sell it, YOU are responsible for it and all aspects of safety.

who ever you buy the equipment from, you need to provide them ALL the specs for safety, wiring requirements, and risk assessments.

yes, the price may go up and probably will, and your price to the customer will go up also, but you have a paper trail showing due diligence to make it right if something happens.

james.

Does this method actually work for you?

We provide specs to ... I'll call them lab-grade .. suppliers. Like either the equipment is made from 316 stainless, or you need to 2-part epoxy-paint all of the steel, and at least the hinges and clasps on the cabinets need to be stainless. T&B relays and bases only. Weidmueller terminals, with proper labels and end caps on the din rails. 3 phase motors that meet our paint spec, TECO preferred vendor.

And we get quotes. Generic quotes. From all of the suppliers. One is selected and the **** arrives with single phase motors, plastic handles on the disconnects, carbon steel cabinets, unlabeled terminals, and drawings that sort of match the cabinets. And we pay them for it .. for some reason. It normally arrives late for our shutdown, so we can't get anything changed, by the vendor, after it arrives. And there is no time to get something from another vendor .. but they all appear to do this ...

Then we rip out their wiring and controls, normally throw out the cabinets, and make something sort-of work. But it's done in a big hurry with whatever we have on hand and it is a nightmare to troubleshoot ... so it then becomes a work-in-progress for a couple of years before we get it operating the way we want it to. And get it cleaned up. Because no one appears to care about specs. And our purchasing department is clueless.
 
I dont know about over there, but over here it would be plainly illegal to import machinery without an EC Declaration of Conformity.
If the machine has its own control system (despite being interlocked with other machines), then it definitely needs a full Declaration of Conformity.

Some machinery parts that are to be incorporated into other machinery dont need it, but they still need a EC Declaration of Incorporation for Partly Completed Machinery. In that case, whoever puts the machine into a greater system is responsible for making the final Declartion of Conformity for the whole machine or plant.

Also, there are some exceptions for existing machinery that has been in use at the same location from before the latest regulations came in force. But that does not apply in your case when you import machinery and put them into operatio today.

I am pretty sure that something similar is required over by you.
Your argument to your management is that regulations have been tightened, and you have to keep up with the regulations.
That you have been importing machinery for 15 years that do not conform to the latest regulations is no argument.

In some countries it is the owner or CEO that is responsible and can go to jail. In some other countries it is the engineer that was put in charge of the job. If it is the first in your country, be sure to inform that person about his personal risk.
 
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Here in the US, anything goes. No Declaration of Conformity required. In my company, we fight the battle with Purchasing, Sales and Management because they know that equipment can come cheap from China or other countries. In an example from a few years ago, we were forced by management to purchase a cutter because a low-cost country (LCC as called here) offered one for $8,000 plus the cost of a boat ride. We could not get any prints ahead of time and they were not interested in a redesign to our specs. "Order it anyway", we were told. "We can fix it when it gets here." We found out later it was mostly a copy of a US company's design, minus anything robust or safe.
After it arrived and I demonstrated that the wiring was sub-standard, the safety circuit was not safe and the machine would not do what we wanted, we sank another $30k into it TO DO A TRIAL. The trial did not go well and it would not handle our processing needs. The machine sits on a storage shelf. We literally have more time in redesign, ordering components and debug of our retrofit than it had running product. It is pitiful.
 
I used to work for a company that shipped al over the world, when they shipped to the states, they got a good surprise. they had to show risk assessments, wiring diagrams, specifications, and a lot of other stuff.

I also worked for an oem and we were given the requirements and specs.
we did risk assessments, safety procedures, and a lot more.
we even did change orders when required. that saved our butts on several occasions. we were cleared of all wrong doing. my customer on the other hand was in a world of hurt.

today, we give these requirements out and it works for us.

james
 
I dont know about over there, but over here it would be plainly illegal to import machinery without an EC Declaration of Conformity.
If the machine has its own control system (despite being interlocked with other machines), then it definitely needs a full Declaration of Conformity.

Some machinery parts that are to be incorporated into other machinery dont need it, but they still need a EC Declaration of Incorporation for Partly Completed Machinery. In that case, whoever puts the machine into a greater system is responsible for making the final Declartion of Conformity for the whole machine or plant.

Also, there are some exceptions for existing machinery that has been in use at the same location from before the latest regulations came in force. But that does not apply in your case when you import machinery and put them into operatio today.

I am pretty sure that something similar is required over by you.
Your argument to your management is that regulations have been tightened, and you have to keep up with the regulations.
That you have been importing machinery for 15 years that do not conform to the latest regulations is no argument.

In some countries it is the owner or CEO that is responsible and can go to jail. In some other countries it is the engineer that was put in charge of the job. If it is the first in your country, be sure to inform that person about his personal risk.

From what I've seen in my career here in the US, there really isn't any proactive enforcement of machinery safety. Official enforcement tends to be of the "if no one got hurt, it must have been safe. If someone got hurt, we might come out and assess penalties." variety. Europe has some good safety standards that are enforced by law; over here i often see people think "the machine has an Estop" is sufficient for most systems.

I'm not excusing the behavior, but it really is common, and there really isn't any law punishing it.
 
Does this method actually work for you?

We provide specs to ... suppliers.

And we get quotes. ... One is selected and the **** arrives ...

Then we rip out their wiring and controls, normally throw out the cabinets, and make something sort-of work.
I had to double check to make sure I didn't write this myself or whether you worked here.

I've spent way too much over the last two years rebuilding a control system because of this. Although we did manage to keep the last payment due the vendor.

The only thing I've found that works is engineering needs to be involved early in the procurement cycle. There has to design reviews before the vendor gets approval to build. Then a factory acceptance check before they ship the stuff. Then a final factory acceptance before it is paid for. We've done it--it's a lot of work. But nice to have something arrive that only needs minor tweaking.

One thing I will add is that a lot of places aren't used to getting detailed specifications. I know a lot of engineers that could spec a method to get out of a paper bag. The above only works if you have a detailed specification and concise contract that lays out performance so there is no wiggle room and lastly this method needs someone who is willing and authorized to say 'no' when the specification and contract are not met.
 
Thank you all for your comments. This is why I asked because I figured I would get some feedback from all different areas of the world.

Jesper:The machines from Europe do have the Declaration which is why they come equipped with the proper Engineering and safety devices according to their regulations.

Mk42: this is exactly the mentality of many people here. I do have to deal with the same comments on a weekly basis.

Don't know if i should say this but it Would be much nicer if the US would adopt an equivelant of Europe or canada, with a "law".

It's just a pain to have open ended answers without some form of documented reference. Because what is safe to one person may or may not be safe to another.

Testsubject:
"Just because you did it a certain way for 15 years does not mean that you should not change with new information" I'm with you on this one!

James/timbert: yes any job we do with a customerwith an organized Engineering Department turns out everyone on the same page. Very smooth. Because at that point the controls and mechanical Department have the stage. Project management has not to much sayso since it is agreed apon and needed to accept the project. Not always that easy though.

Drforsythe: I feel you pain. Lol
 
Don't know if i should say this but it Would be much nicer if the US would adopt an equivelant of Europe or canada, with a "law".

It's just a pain to have open ended answers without some form of documented reference. Because what is safe to one person may or may not be safe to another.

For what it's worth, we do have NFPA79, but I've always gotten the impression that it was more of a requirement by insurance companies than the government. They don't really care about people getting hurt, they just don't want to pay your bills in a lawsuit.
 
I’m not a lawyer so this may be off base but In the US there are 2 types of courts, Criminal and Civil. If someone gets hurt by a machine the Criminal responsibility is on the machine owner only. The builder will not be sued in criminal court. The government agency known as OSHA handles these events and hands out fines. You can look up their investigations and reports online.

When it gets to civil court, anyone who touched the machine is a potential target.
 
I’m not a lawyer so this may be off base but In the US there are 2 types of courts, Criminal and Civil. If someone gets hurt by a machine the Criminal responsibility is on the machine owner only. The builder will not be sued in criminal court. The government agency known as OSHA handles these events and hands out fines. You can look up their investigations and reports online.
I am sure that if a builder of a complex maschine stated it was safe, then the owner can refer to that in court.
If because of a manufacturing defect the steering in your car breaks down while driving, and you veer off and hits and kills someone, are you the owner or the car liable when you have no reason to suspect that the steering was defective ? Assuming you have used and maintained the car according to the manufacturers specifications.

mk42 said:
From what I've seen in my career here in the US, there really isn't any proactive enforcement of machinery safety.
In the EU it is mandatory that all businesses have someone who is responsible for safety. edit: there is no government body that proactively enforces safety at the workplace.
In a factory that person shall arrange safety training, and that all machines are safe and properly maintained. Since it is in praxis impossible for end-users to evaluate the safety of complex machines, the Declaration of Conformity, manufacturers safety instructions etc. is a crucial part of keeping a large plant safe.
The Declaration of Conformity is 'only' a legal document. It means the owner can assume the maschine is safe. And if there is an accident due to failure of design or manufacture, the document places the responsibility.

I think that possibly the difference between over here and over there is that this declaration is mandatory by law in the EU.
I assumed that something similar was law over by you. If it is not, then it surprises me as I always thought that the US was at the forefront for safety, if nothing else at least the legal part.
 
I am sure that if a builder of a complex maschine stated it was safe, then the owner can refer to that in court.
If because of a manufacturing defect the steering in your car breaks down while driving, and you veer off and hits and kills someone, are you the owner or the car liable when you have no reason to suspect that the steering was defective ? Assuming you have used and maintained the car according to the manufacturers specifications.

In the US, pretty much everybody who touched the machine gets hauled into court. It's less a matter of "innocent/guilty" or "liable/not liable", and more a matter of "how much is each party going to pay". Unless you can prove the injured party was completely negligent, they're getting money. And even then, you might pay anyway.

In the EU it is mandatory that all businesses have someone who is responsible for safety. edit: there is no government body that proactively enforces safety at the workplace.
In a factory that person shall arrange safety training, and that all machines are safe and properly maintained. Since it is in praxis impossible for end-users to evaluate the safety of complex machines, the Declaration of Conformity, manufacturers safety instructions etc. is a crucial part of keeping a large plant safe.
The Declaration of Conformity is 'only' a legal document. It means the owner can assume the maschine is safe. And if there is an accident due to failure of design or manufacture, the document places the responsibility.

I think that possibly the difference between over here and over there is that this declaration is mandatory by law in the EU.
I assumed that something similar was law over by you. If it is not, then it surprises me as I always thought that the US was at the forefront for safety, if nothing else at least the legal part.

Interesting. I had always heard that on your side of the ocean, if the machine builder followed the proper standards and provided that Declaration of Conformity, they were off the hook for anything that happened.

Over here, I think a big part of it is there is no acknowledgment that it is "in praxis impossible for end-users to evaluate the safety of complex machines". The only real LAW is that the employer SHALL provide a safe workplace. Which means they are ultimately responsible for everything in their building.
 
Interesting discussion!

Around here, the proper way of doing a risk assessment:

* Identify risks
* Identify/calculate probability
* State your accepted risk probability (supposed to be stated by plant owner, which will be responsible for safety of workers, environment and the public)
* Calculate what SIL/other precautions needed to achieve an accepted risk probability

The risk is never going to be zero. Are you supposed to be responsible for a life time when there's a calculated risk if something happens?
 

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