Ground Fault protection for welders

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dvcraven0522

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I have designed for 90A/2p breaker to feed a welder in a truck maintenance area. The inspector requires the circuit to be GFCI protected. I can only find a 60A/2p with GFCI protection.

Not sure they make a 90A CB with GFCI. Any suggestion how I might achieve what the inspector is asking for would very much be appreciated.

DanCraven
 
Did he sight a code to reference the requirement? I didn't see requirements for GFCI in 630.
 
Siemens has 480V rated breakers that you can put on a GFCI or GFP protection kit and a small load center enclosure, 2 or 3P. But they are expensive.
 
Rock86 said:
Did he sight a code to reference the requirement? I didn't see requirements for GFCI in 630.
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If it is connected via cord/plug, 210.8 (B) would require GFCI protection at least at the receptacle in a garage/service bay/similar areas.

However OP says 90 amp 2 pole breaker is what he needs - 210.8 (B) doesn't require GFCI over 50 amps single phase, but does say "single phase receptacles" and not single phase branch circuits, so could be some technicalities at work here depending on what you may have for a receptacle.
 
kwired said:
If it is connected via cord/plug, 210.8 (B) would require GFCI protection at least at the receptacle in a garage/service bay/similar areas.

However OP says 90 amp 2 pole breaker is what he needs - 210.8 (B) doesn't require GFCI over 50 amps single phase, but does say "single phase receptacles" and not single phase branch circuits, so could be some technicalities at work here depending on what you may have for a receptacle.
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Thats why I asked if the OP had received a code reference.
 
kwired said:
If it is connected via cord/plug, 210.8 (B) would require GFCI protection at least at the receptacle in a garage/service bay/similar areas.
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Personally, I think any GFCI will instantly trip the moment anyone draws an arc with a 90 amp welder.

Hopefully I'm wrong, because that will just put someone between a rock and a hard place.
 
Not that I am aware of. But I believe since its in a shop maintenance area.

I have since found a Siemens molded case breaker that has GFCI module sensing element. Basically it takes up a (1) pole space next to the breaker.
 
ptonsparky said:
I see one is 5 ma.
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Yes, but it doesn't specifically say it is Class A, it specifically says it is equipment protection only.

The term "GFCI" is specific to a Class A ground fault protection device for protection of personnel and requires listing to that effect. If the Siemens product had it, they would state it.

I think your only option is to see if the inspector will allow a non-Class A GFEP breaker with a 5mA trip (the Siemens option), or hard wire it. I don't think anyone is making 3 pole Class A GFCIs yet.
 
Jraef said:
Yes, but it doesn't specifically say it is Class A, it specifically says it is equipment protection only.

The term "GFCI" is specific to a Class A ground fault protection device for protection of personnel and requires listing to that effect. If the Siemens product had it, they would state it.

I think your only option is to see if the inspector will allow a non-Class A GFEP breaker with a 5mA trip (the Siemens option), or hard wire it. I don't think anyone is making 3 pole Class A GFCIs yet.
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Non NEC countries such as UK require GFPE which is exactly the same as GFCI but with a much higher cutoff...50 mA. GFCI is for personnel and as stated it is only on small receptacles. It used to be 120 V only but recently expanded to 240 V which has had the consequence of snaring some small generators.

Beyond that NEC requires ground fault protection on large loads. They keep changing the criteria but generally 800 A+. At that point most breakers use electronic trip units so it’s just a microprocessor tripping on excess neutral current.

In some countries (again popular in UK) as well as certain industries (mining, chemicals) and a lot of medium voltage equipment high resistance grounding is used in three phase systems with typically a 1 to 15 A trip with a delay of say 1 second at the fastest or alarm only (no trip) in some cases. Even at 4160 with the right size resistor fatal shocks in the to ground become impossible. Not to say it won’t hurt (90 nA) but it’s not fatal (100 mA).
 
steve66 said:
Hmm.... that says equipment protection only. Does the code require Class A GFCI for people?
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When code mentions "ground fault circuit interruptor (GFCI)" it is referring to Class A GFCI protection.
When it mentions "ground fault protection" (possibly adding "equipment") it is referring to applications up to 100mA trip unless a level is specified.
 
dvcraven0522 said:
I'll do better than that. See attached.
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Looks like a line somewhat equivalent to Square D I-Line. Not going to just snap that in an existing loadcenter. Single breaker in it's own separate enclosure might be possible though. Bet they proud of them when it comes to price, just like anyone else would be.
 
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