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Old October 11th, 2018, 04:06 AM   #31
Saffa
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Another thing us crazies with 230V use is RCDs. At least for lights and sockets where Joe Public generally comes into contact with the zappy bits.
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Old October 11th, 2018, 06:08 AM   #32
Lynx777
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Just my 2 cents. I used to work on a lot of older (ancient) molders and saws in a lumber mill. Almost every one of them was set up with 480 vac controls. A few had been rewired for 120 vac control. Either way, industrial GFCI's were a relatively easy way to make them safer until time and money could be obtained to upgrade the controls.
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Old October 11th, 2018, 06:47 AM   #33
JesperMP
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110V or 230V AC on operating elements are OK, as long as the entire circuit and enclosures are rated for it.
Same as the light switch in the wall switches the 120V or 230V AC directly.
That being said, it is becoming rarer since universally the preference is 24V DC.

About being zapped by 110V or 230V, then the person being zapped is himself to blame by assuming things. Any enclosure within which there is a dangerous voltage must be clearly labelled as such. And there must be a sign insde or outside clearly stating the control voltage used.
No such label or sign ? Well then investigate it before mindlessly touching live circuits !

Just saying...
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Old October 11th, 2018, 02:39 PM   #34
James Mcquade
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I haven't read the entire posts here, but nfpa79 - industrial standard for industrial machinery dictates that no new control panels shall have control voltages above 120 volts ( that might have changed recently).
that section of the code is pretty old.
systems built before that rule was implemented was grandfathered in.

I don't have my book with me, I packed it during the move to my new job.
if I a wrong, someone please correct me.

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Old October 11th, 2018, 03:37 PM   #35
lesmar96
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Thanks James,

That is what I was looking for. I didn't know where to look.

I looked up the 2018 NFPA 79 and found similar
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Old October 12th, 2018, 01:57 PM   #36
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Quote:
Originally Posted by JesperMP View Post
110V or 230V AC on operating elements are OK, as long as the entire circuit and enclosures are rated for it.
Same as the light switch in the wall switches the 120V or 230V AC directly.
That being said, it is becoming rarer since universally the preference is 24V DC.

About being zapped by 110V or 230V, then the person being zapped is himself to blame by assuming things. Any enclosure within which there is a dangerous voltage must be clearly labelled as such. And there must be a sign insde or outside clearly stating the control voltage used.
No such label or sign ? Well then investigate it before mindlessly touching live circuits !

Just saying...
I agree and it is pretty much the same as proving zero energy which means labels or not and regardless of how big the signs are the person exposed to the hazard has the obligation and responsibility to know exactly what is there or not there.
The answer to the original question however does not change, 24V is the better choice for all the reasons given in this thread.
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Old October 12th, 2018, 03:42 PM   #37
Aabeck
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Quote:
Originally Posted by kalabdel View Post
...the person exposed to the hazard has the obligation and responsibility to know exactly what is there or not there....
My fear is not that a technician opening the panel is not going to realize the danger of the control voltage, it is the operator that may be in danger if the control voltage gets to the surface of the pushbutton or switch, as was what happened in my post of the operator getting electrocuted at a header shop here in Detroit.
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Old October 12th, 2018, 04:45 PM   #38
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Quote:
Originally Posted by Aabeck View Post
My fear is not that a technician opening the panel is not going to realize the danger of the control voltage, it is the operator that may be in danger if the control voltage gets to the surface of the pushbutton or switch, as was what happened in my post of the operator getting electrocuted at a header shop here in Detroit.
I absolutely agree.
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