Lobster tank GFCI protection?

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Ingenieur said:
they do not agree with you
they require gfci in many locations
homes first, then expanded to other occupancies
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GFCIs are not required because EGCs have to high a Z and/or breakers take to long to trip. They were brought into the code primarily due people being killed on metal frame tools.



you miss the point
when wet you may bypass the egc, become the gf path
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Same can happen when dry. The IEC calls it direct contact.

and even with an egc it may limit i < the threadhold, where as without it you may die
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Yes it can limit the threshold, but current NEC practices in no way cause a ground fault to be lethal or damaging when the EGC is the right size and the correct breaker is used. Table 250.122 is well thought out.
 
Historically GFCI has mostly only been required for receptacle outlets. I believe the reason is higher risk of a compromised EGC.

Even now with commercial kitchens, it is still only for receptacles as the general rule. If you have a choice of "hardwiring" vs "cord and Plug" on a particular appliance -the hardwired installation won't require GFCI. Now in 2017 NEC they added more receptacles as well. I don't necessarily agree that they needed to add all of them but still is only for receptacle outlets.
 
kwired said:
Historically GFCI has mostly only been required for receptacle outlets. I believe the reason is higher risk of a compromised EGC.

Even now with commercial kitchens, it is still only for receptacles as the general rule. If you have a choice of "hardwiring" vs "cord and Plug" on a particular appliance -the hardwired installation won't require GFCI. Now in 2017 NEC they added more receptacles as well. I don't necessarily agree that they needed to add all of them but still is only for receptacle outlets.
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True- commercial kitchens often end up with missing ground pins. One of the most eye opening threads:



http://forums.mikeholt.com/showthread.php?t=172466&p=1682020#post1682020
 
mbrooke said:
True- commercial kitchens often end up with missing ground pins. One of the most eye opening threads:



http://forums.mikeholt.com/showthread.php?t=172466&p=1682020#post1682020
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And IMO the 5-15 and 5-20 cord caps are the worst for losing the EGC pin. Sure there is intentional removal of them on occasion, but they do end up breaking off easier from mishandling then the EGC of almost any other plug type, and I believe this is part of why GFCI protection expanded to most of the locations it did, along with many of those locations having higher possibility of contact with a grounded surface.

Used to be exceptions to some GFCI's if you could prove you had an assured EGC program, which also indicates that a compromised EGC was recognized as a problem here. Was still probably easier to use GFCI's then to implement a program to assure all the EGC's are intact. OSHA probably still wants to see EGC's intact though.
 
590.6(B)(2) only applies to certain circuits. Not that I have ever seen implemented on the job site anyways. Way too much trouble IMO.

And if were to implemented, it does not apply to GP circuits on a construction site.

From don g in a another thread on this topic:

Note that 590.6(B) does not apply to 125 volt, 15, 20 or 30 amp receptacle outlets. You are not permitted to use the assured equipment grounding program in lieu of GFCI protection for 125 volt, 15, 20 or 30 amp receptacle outlets.
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kwired said:
And IMO the 5-15 and 5-20 cord caps are the worst for losing the EGC pin. Sure there is intentional removal of them on occasion, but they do end up breaking off easier from mishandling then the EGC of almost any other plug type, and I believe this is part of why GFCI protection expanded to most of the locations it did, along with many of those locations having higher possibility of contact with a grounded surface.

Used to be exceptions to some GFCI's if you could prove you had an assured EGC program, which also indicates that a compromised EGC was recognized as a problem here. Was still probably easier to use GFCI's then to implement a program to assure all the EGC's are intact. OSHA probably still wants to see EGC's intact though.
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I agree. The ground pin is hard and does not bend well while the live and neutral pin are actually flexible. If someone yanks on the cord side to side it very easy for the ground pin to just snap while the rest just bends. I think we made a mistake by not taking the original Hubell patent of 3 flat pins.



jumper said:
590.6(B)(2) only applies to certain circuits. Not that I have ever seen implemented on the job site anyways. Way too much trouble IMO.

And if were to implemented, it does not apply to GP circuits on a construction site.

From don g in a another thread on this topic:
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It won't be long until GFCI or GFP is required on all circuits of every voltage. Its only a matter of time...especially with our current CMPs... However my argument being history and evolution. GFCIs have less to do with water and more to do with EGCs in terms of what got them into the code and helped them spread.


https://www.osha.gov/SLTC/etools/construction/electrical_incidents/aegcp.html
 
mbrooke said:
I did on my first post in this thread, here:


http://forums.mikeholt.com/showthread.php?t=192766&page=2&p=1932123#post1932123


What came after was the assertion that an EGC is not sufficient protection among others.
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Nope.

No such assertions were made.

All said GFCI not required. A few said it was not a bad idea though.

The whole idea of one over the other was your idea, you wanted that spin.
And make no doubt, I am well versed in the history of GFCIs and EGCs, and their NEC development and how they may or may not be intertwined fulfilling their functions.

This argument had nothing to do with any previous assertion in this thread.
 
jumper said:
Nope.

No such assertions were made.

All said GFCI not required. A few said it was not a bad idea though.

The whole idea of one over the other was your idea, you wanted that spin.
And make no doubt, I am well versed in the history of GFCIs and EGCs, and their NEC development and how they may or may not be intertwined fulfilling their functions.

This argument had nothing to do with any previous assertion in this thread.
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Assertion can be found here:

http://forums.mikeholt.com/showthread.php?t=192766&page=2&p=1932162#post1932162


wrong
an egc does not prevent shock with a hi z fault
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To which a debate about that started from there.

In any case we can agree to disagree if an EGC alone is sufficient protection. Nothing hurts having a GFCI at the lobster tank, but IMO as long as the equipment has an EGC I am not worried about safety to personnel.
 
mbrooke said:
In any case we can agree to disagree if an EGC alone is sufficient protection. Nothing hurts having a GFCI at the lobster tank, but IMO as long as the equipment has an EGC I am not worried about safety to personnel.
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Who the heck is disagreeing that an EGC alone is not sufficient protection per NEC?

Not me, Iggy, or anyone else.

Now are there various scenarios in which standard rules apply, or extra protection is needed, or times which one form of protection would be more beneficial? Yes.

Those we can discuss, no problem, but the high z fault mentioned was a conditional excercise.
Not a direct answer to OP.
 
jumper said:
Who the heck is disagreeing that an EGC alone is not sufficient protection per NEC?

Not me, Iggy, or anyone else.

Now are there various scenarios in which standard rules apply, or extra protection is needed, or times which one form of protection would be more beneficial? Yes.

Those we can discuss, no problem, but the high z fault mentioned was a conditional excercise.
Not a direct answer to OP.
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I'm sure it was conditional, a what if, however its being said that if a High Z fault occurred an EGC would not stop a shock. Therefore by the power of logic I can only conclude that the belief held is that an EGC is insufficient protection- that some internal faults will cause user to be shocked. But where I am coming from is that if you took a 30,000 ohm resistor, or even a 100 watt light bulb line to grounded frame- the voltage will never reach dangerous or even significantly uncomfortable levels. At most a few volts. Therefore IMO an EGC offers shock protection.


Now if the OP was to add a GFCI, I'd have no issue. There is nothing wrong with extra protection.
 
mbrooke said:
Now if the OP was to add a GFCI, I'd have no issue. There is nothing wrong with extra protection.
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See, we is all in harmony. Good.:thumbsup:

The argument you really wish to discuss has more to do with the 1996 change to 250.140 for ranges and dryers, and/or the history and debate around 250.130 and replacement receptacles in regards to providing an EGC or GFCI protect old 2 wire supplied receptacles.

Well.....I ain’t going there in this thread.
 
mbrooke said:
Assertion can be found here:

http://forums.mikeholt.com/showthread.php?t=192766&page=2&p=1932162#post1932162

To which a debate about that started from there.

In any case we can agree to disagree if an EGC alone is sufficient protection. Nothing hurts having a GFCI at the lobster tank, but IMO as long as the equipment has an EGC I am not worried about safety to personnel.
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gf z : xfmr + service + branch + egc + fault ~ 2 ohm
body z: small person/child, wet , 100 lb
i fault 120/2 = 60 A
person i = 2/600 x 60 = 200 ma, in parallel with egc gf loop
fault initiated by wet person touching

threshhold
dalziel t = (100/200)^2 = 0.25 sec
your chart: 200 ma for 0.50 sec

20/1 cb clearing time (3 x Ir or 300%) ~ 20-40 sec, avg 30
https://download.schneider-electric...73.1851232153.1532893196-833456241.1523677640
30 sec > 0.25 or 0.50 sec
likely death

you know not of what you speak
it is good you have no authority or influence in these matters
you would be a danger to others
 
jumper said:
See, we is all in harmony. Good.:thumbsup:

The argument you really wish to discuss has more to do with the 1996 change to 250.140 for ranges and dryers, and/or the history and debate around 250.130 and replacement receptacles in regards to providing an EGC or GFCI protect old 2 wire supplied receptacles.

Well.....I ain’t going there in this thread.
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Errrr- no. I brought up ranges and dryers because they are basically a High Z fault. People aren't getting shocked with a motor dropping 8 amps to a conductor bonded to the frame, and people won't be getting shocked with 5 or 500ma being conducted to the frame of a grounded object.
 
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