Reasoning?

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Smart $ said:
I don't think you're reading that right. The way I read it, only a gennie with twist lock recept' is required to have GFCI 15 & 20A receptacles... but if an interlock (neither mechanical or electrical is specified) defeats their availability while the twist lock is in use, GFCI is not required. If no twist lock, no GFCI is required.

IOW, for any portable generator up to 15kW with a 125/250V twist-lock receptacle, all 15- & 20A 125V receptacles must either be GFCI-protected or unusable while the twist-lock is in use.
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That was what I said... a twist lock will force a GFCI (ok not always:p). There is the interlock but Id imagine makers would just opt for a GFCI.


The interlock is just strange. I cant see how it will make anything safe. A tool plugged into a 120 volt outlet is just as much of a risk whether or not a twist lock is in use.
 
mbrooke said:
That was what I said... a twist lock will force a GFCI (ok not always:p). There is the interlock but Id imagine makers would just opt for a GFCI.


The interlock is just strange. I cant see how it will make anything safe. A tool plugged into a 120 volt outlet is just as much of a risk whether or not a twist lock is in use.
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And that's why I said they should have just stuck with requiring the 120V recept's to be GFCI.
 
mbrooke;1615254.... I don't think they even tried to idiot proof: ....[/QUOTE said:
Paraphrased quote - not attributable to me.

Engineers are in a constant battle with the universe. The Engineers are working to build better idiot proof equipment. The universe is constantly building better idiots. So far the universe is winning.
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iceworm said:
Paraphrased quote - not attributable to me.

Engineers are in a constant battle with the universe. The Engineers are working to build better idiot proof equipment. The universe is constantly building better idiots. So far the universe is winning.
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:lol: Good one :)
 
There is a TIA on this, that adds a Jan 1 2015 effective date.
There was considerable discussion from the generator mfgs in 2014 ROC.
>>Gen with a float neutral is safer as there is no shock path
>>Gen with GFCI may not be effective as GFCI depends on path to ground - generator with rubber tires would not have that.
 
tom baker said:
There is a TIA on this, that adds a Jan 1 2015 effective date.
There was considerable discussion from the generator mfgs in 2014 ROC.
>>Gen with a float neutral is safer as there is no shock path
>>Gen with GFCI may not be effective as GFCI depends on path to ground - generator with rubber tires would not have that.
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Rubber tires are irrelevant, keep in mind electricity is looking for the source, not ground. Also, In theory 2 ground faults could trip one or both GFCIs. To be honest I don't see what bad would happen putting a GFCI on an ungrounded system. If the capacitive leakage current is not high enough, no trip. If it is one or both GFCIs trip.


Also, a floating neutral may be safer, but not always. An incandescent socket depends on a grounded conductor. In an ungrounded system you loose the reference, especially with a long standing ground fault on the hot leg somewhere in the system.
 
tom baker said:
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>>Gen with GFCI may not be effective as GFCI depends on path to ground - generator with rubber tires would not have that.
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The shock also depends on the path to ground, if there is no path because of the rubber tires, there is no shock hazard.
 
How can anyone argue that a GFCI will not work without a connection to ground?
With an ungrounded system there will be no trip without a double fault, and the differential/residual current detector will work just fine under those circumstances to protect a person is part of one of the fault paths.
The one case where GFCI may not work is where there is no line to neutral voltage present, whether the neutral is grounded or not.
 
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GoldDigger said:
How can anyone argue that a GFCI will not work without a connection to ground?
With an ungrounded system there will be no trip without a double fault, and the differential/residual current detector will work just fine under those circumstances to protect a person is part of one of the fault paths.
The one case where GFCI may not work is where there is no line to neutral voltage present, whether the neutral is grounded or not.
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I agree. It may not work right, but it would still protect the person.

IMO I think the people who are on this forum are so well educated in electrical theory that they would be a profound asset to the CMP. That would also mean you GoldDigger:D
 
don_resqcapt19 said:
The very reason that "portable" (plug-in) GFCI devices are required to have open neutral protection.
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Presumably implemented by using NO contacts whose coil requires power to set in the first place instead of the mechanically latched active trip contacts of a hard wired GFCI receptacle or breaker?
 
GoldDigger said:
Presumably implemented by using NO contacts whose coil requires power to set in the first place instead of the mechanically latched active trip contacts of a hard wired GFCI receptacle or breaker?
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That would be my guess, but I don't know for sure. I do know that they have changed how they work as with the older ones, you had to push the reset button each time you plugged the device in. You don't have to do that with the new ones. However a coil and NO contacts would work for either operation, but the older operation would require a "seal-in" contact, and the new operation probably just connects the coil directly to the line side power.
 
I know a little late but I came across this:


ENGINE GENERATORS FOR PORTABLE
USE (FTCN)
GENERAL
This category covers internal-combustion-engine-driven generators rated
15 kW or less, 250 V or less, which are provided only with receptacle outlets
for the ac output circuits. The generators may incorporate alternating or
direct-current generator sections for supplying energy to battery charging
circuits.
When a portable generator is used to supply a building wiring system:
1. The generator is considered a separately derived system in accordance
with ANSI/NFPA 70, ??National Electrical Code?? (NEC).
2. The generator is intended to be connected through permanently
installed Listed transfer equipment that switches all conductors other
than the equipment grounding conductor.
3. The frame of a Listed generator is connected to the equipment grounding
conductor and the grounded (neutral) conductor of the
generator. When properly connected to a premises or structure, the
portable generator will be connected to the premises or structure
grounding electrode for its ground reference.
4. Portable generators used other than to power building structures are
intended to be connected to ground in accordance with the NEC
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Guess even in portable applications it must be separately derived no matter what.
 
mbrooke said:
I know a little late but I came across this:

Guess even in portable applications it must be separately derived no matter what.
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That would be assuming that you have a listed portable generator. There is no requirement to use a listed portable generator.
 
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