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Old October 9th, 2018, 05:46 PM   #16
kalabdel
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Originally Posted by Toine View Post
Common voltage in Europe between neutral and phase is 230VAC rather than 120. Between two phases we have 400VAC. Other than that you are completely right, and I have made the same mistake once, assuming a panel had 24V control voltage while in fact it was 230V. I wasn't hurt, nobody else either. I did realize that I was lucky, learned my lesson and have been careful ever since: never assume - always test.
You're correct it was 230V. But on never assume, and I realize I'm no longer in the electrical code realm and getting into legal issues that are beyond my expertise expect for having been sued for injuries caused by equipment we maintained, if 99 of the push buttons (as an example) in one market have 24V , in the event of an incident and especially if fatal the question will come up and rightfully so. Another question that always comes up is if it was foreseeable and preventable and again if the question (24V vs 240V) was asked during design then the answer is yes.
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Old October 9th, 2018, 06:07 PM   #17
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I was in a header shop a few years ago. The coil reel/straighteners were mostly 230V controls.

An operator a few machines away from me was holding the Jog PB and grabbed the end of the wire as it came out of the unit and immediately started screaming and shaking - he was getting the full 230VAC and it was holding him to the machine. Lucky for him the operator on the next machine knew enough to not try and pull him off, so he made a running tackle to break him free.

After seeing that I decided all my controls will be 24VDC unless there absolutely has to be something higher.
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Old October 9th, 2018, 06:45 PM   #18
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Originally Posted by lesmar96 View Post
I guess this is really what prompted my question and several of you have brought it up. Starter panels..........

When all you have is a starter panel mounted on the wall, with a start/stop buttons in the front, it is easiest to simply use the line voltage.

We get these requests various times and I was not sure what is the proper way of doing. It is a pain, although the safest, to use a control transformer.

What we build and sell, generally is a poly enclosure, so if that button would somehow fail, the next person to touch it could potentially be the next path to ground.
If I build it, I will use 24vdc where possible, and compromise at 120vac if I have to, but I won't put any higher voltage on a push button or selector switch than that.

If someone else builds it and I get a call "my pump won't run" and I go out to reset the OL relay or troubleshoot, I proceed with extreme caution. I have seen enough crazy and/or crappy stuff in panels in the water and waste water industry that every day I thank God for my private well. Whatever you are paying for water, it isn't enough. Most of the controls I have looked at (>80%) are in horrible condition.
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Old October 10th, 2018, 03:09 AM   #19
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If I build it, I will use 24vdc where possible, and compromise at 120vac if I have to, but I won't put any higher voltage on a push button or selector switch than that.

If someone else builds it and I get a call "my pump won't run" and I go out to reset the OL relay or troubleshoot, I proceed with extreme caution. I have seen enough crazy and/or crappy stuff in panels in the water and waste water industry that every day I thank God for my private well. Whatever you are paying for water, it isn't enough. Most of the controls I have looked at (>80%) are in horrible condition.
I think its a problem with a lot of smaller water utilities. Here too. They pay peanuts so they get monkeys for engineers. Or worse, there's no electrical engineer on staff to make sure things get done right. No standards... and money wasted on stuff that isn't required. Things don't get replaced until they're either on fire or broken beyond repair.
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Old October 10th, 2018, 07:52 AM   #20
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Quote:
Originally Posted by Aabeck View Post
I was in a header shop a few years ago. The coil reel/straighteners were mostly 230V controls.

An operator a few machines away from me was holding the Jog PB and grabbed the end of the wire as it came out of the unit and immediately started screaming and shaking - he was getting the full 230VAC and it was holding him to the machine. Lucky for him the operator on the next machine knew enough to not try and pull him off, so he made a running tackle to break him free.

After seeing that I decided all my controls will be 24VDC unless there absolutely has to be something higher.
Why is this so popular in Europe, when it is to dangerous?

So it seems there is really no specific code that details this, it is just a matter of safety, that 230 is much more dangerous than 24.
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Old October 10th, 2018, 08:17 AM   #21
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Originally Posted by lesmar96 View Post
Why is this so popular in Europe, when it is to dangerous?

So it seems there is really no specific code that details this, it is just a matter of safety, that 230 is much more dangerous than 24.
I wouldn't call it popular...

And while it is a completely different environment, everyone in Europe will have 240Vac at home. So one can say that the risk tolerance is already at that level and, to save cost, people use it in industry (they shouldn't really).

One thing that many countries in Europe will have and will be enforced is checks on equipment to ensure that it is safe to operate. So the case where a wire was loose and came into contact with the operator, I would say that the equipment was clearly not fit for use, but no one did anything about it. I know, it's after the fact, but is a protection.

I'm not trying to excuse this, I am moving equipment that was put on with 110Vac and everything will be "upgraded" to 24Vdc as standard, but there are reasons why things may be done that way.
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Old October 10th, 2018, 11:07 AM   #22
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Originally Posted by lesmar96 View Post
I guess this is really what prompted my question and several of you have brought it up. Starter panels..........

When all you have is a starter panel mounted on the wall, with a start/stop buttons in the front, it is easiest to simply use the line voltage.

We get these requests various times and I was not sure what is the proper way of doing. It is a pain, although the safest, to use a control transformer.

What we build and sell, generally is a poly enclosure, so if that button would somehow fail, the next person to touch it could potentially be the next path to ground.
Meh... you’d be hard pressed to find a push button made with all conductive parts now. The “failure mode” of a typical PB is that it just doesn’t pass current through the contacts when it is supposed to.

The bigger issues now are that as mentioned, line voltage control doesn’t play well with automation of any kind, and that most people don’t like having line voltage wiring running across the hinge to the door. Flexing of the conductors across the hinge or getting pinched by the hinge is the most common failure mode of control wires. When using line voltage, that’s the big danger and in fact might represent an arc flash danger that would require someone to be suited up in higher PPE just to “interact with the equipment”, meaning to push that button! Nobody wants that...
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Old October 10th, 2018, 12:06 PM   #23
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One of the companies I used to work for is moving towards "no voltage greater than 50V" on any door. This was developed from doing Risk assessments and determining it was safer to do this. Also any grounding into an enclosure had to contact the enclosure first (not land on a panel and go back to the enclosure) to ensure it is grounded. I could see this becoming an industry standard in the future....
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Old October 10th, 2018, 01:38 PM   #24
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Meh... you’d be hard pressed to find a push button made with all conductive parts now. The “failure mode” of a typical PB is that it just doesn’t pass current through the contacts when it is supposed to.
this is right. I had thought of that during this discussion because, how can you get shocked from a plastic push button. but true, wires breaking or shorting out and coming loose
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Old October 10th, 2018, 04:48 PM   #25
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Why is this so popular in Europe, when it is to dangerous?
I travelled to Europe a couple years ago and rented an apartment for the month - a lot less than a hotel.

The circuit breaker box was a few Siemens DIN mounted single pole breakers - Line-2 went straight to the lights and outlets. No neutral wires anywhere, every wire had a 230 potential to ground through a body.

The machines I work on from Europe - mostly Germany and Italy - are wired the same way. There is always one side of the 230 going to each device whenever the main disconnect is on, even before the MCR or MC0 is engaged.
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Old October 10th, 2018, 05:19 PM   #26
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This week I worked on a bran new natural gas furnaces, incorporation it into me control system, all control signals coming out of this thing is 230V AC, so this is still going strong.
(The Furnaces is German by the way)
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Old October 10th, 2018, 05:59 PM   #27
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The one thing I will say they do right over there - all the electrical outlets were at least 5 feet off the floor - way out of reach of kids with paper clips. Of course - I didn't come across one GFCI outlet.

And, for the kids benefit, all the light switches were low. I had to stoop down to get to them.
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Old October 10th, 2018, 06:11 PM   #28
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Quote:
Originally Posted by Aabeck View Post
I travelled to Europe a couple years ago and rented an apartment for the month - a lot less than a hotel.

The circuit breaker box was a few Siemens DIN mounted single pole breakers - Line-2 went straight to the lights and outlets. No neutral wires anywhere, every wire had a 230 potential to ground through a body.

The machines I work on from Europe - mostly Germany and Italy - are wired the same way. There is always one side of the 230 going to each device whenever the main disconnect is on, even before the MCR or MC0 is engaged.
You realize of course that this is how their systems work, right? They have 400V 3 phase 4 wire, and phase to neutral is 230V. ALL of their single phase power is that way.



That's the equivalent of someone here having a 208V 3ph 4W system and using Phase to N for 120V control. It's done all the time. That's not the same as using 480V L-L for your control system.
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Old October 10th, 2018, 07:30 PM   #29
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Jraef,


I work on 400V machines that have a neutral, but the machines I am referring to are 230V, no neutral. Only one side of the 230 is controlled and the other terminal will get one zapped even with the MCR off. Having to troubleshoot these with the power on is a problem.
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Old October 11th, 2018, 04:58 AM   #30
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The one thing I will say they do right over there - all the electrical outlets were at least 5 feet off the floor - way out of reach of kids with paper clips. Of course - I didn't come across one GFCI outlet.
On a residential property???
Not sure what country you were in, but do not assume that is an European thing. I can safely say all the sockets at my house are one foot from the floor.

What they do have in the UK at least, is a safety shield on the sockets. The ground pin is usually longer than the live pins and pushes the shield out of the way to avoid kids getting zapped with clips. This is UK only though.

Quote:
Originally Posted by Aabeck View Post
The circuit breaker box was a few Siemens DIN mounted single pole breakers - Line-2 went straight to the lights and outlets. No neutral wires anywhere, every wire had a 230 potential to ground through a body.

The machines I work on from Europe - mostly Germany and Italy - are wired the same way. There is always one side of the 230 going to each device whenever the main disconnect is on, even before the MCR or MC0 is engaged.
One thing to remember is that a lot of Europe has been there for centuries and some people didn't bother upgrading their electrics or went with the cheapest for a false sense of security.
I mean, I remember going out with my dad installing earth rods because "since the plumber came to fix the pipework the washing machine zaps people"...

I cannot see how there were no neutral wires, or ground anywhere. Did you open a socket?
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