GFCI versus FI from IEC Standard

[Gustav]

Hello,

can anyone explain me why the GFCI acc. UL or NEC does have a failure current of 5mA only and the IEC Version (i.e. FJ) does need only 30mA.

I would appreciate if one could explain it to me in brief words.

Thanks
Best regards
Gustav

 

[don_resqcapt19]

Because 30mA is above the "let go" current for most people and will not provide any real protection to a human.

 

[pbeasley]

Hello,

can anyone explain me why the GFCI acc. UL or NEC does have a failure current of 5mA only and the IEC Version (i.e. FJ) does need only 30mA.

I would appreciate if one could explain it to me in brief words.

Thanks
Best regards
Gustav

in the US 5ma GFCI are intended to protect people, while 30ma GFCI are intended to protect Equipment.

When you refer to the IEC numbers, are you referring to RCID protection? This is similar to, but not the same as, GFCI. They fulfill the same basic function, but the means to achieve the end are usually not the same. IRC the EU uses 30ma RCID for personnel (most countries require this for ALL convenience recptacles 20amp or less) and 100ma RCID for equipment.

Hope this helps.

 

[jim dungar]

The Technology Research Inc website has a pretty good FAQ section that discusses European and US differences.

Go to http://www.trci.net/ , select the FAQ from the left hand menu, then choose the HP-Pro section.

 

[Lxnxjxhx]

GF, more stuff

GF, more stuff

If you use the Forum search feature and search on
1.43
you will find the time vs. current formula for GF devices according to a UL spec.

And there are other posts that cite the effects of current on the human body, in addition to the personal experiences of Forum members.

Seien Sie vorsichtig, Gustav!

 

[Gustav]

Hello,

thanks for your great informations.

At least I do have some more detailed questions
1)
If the 5mA limit is much better than the 30mA limit
Why are not many people hurt in IEC countries while there is the 30mA limit common and additionally there is in most countries the Voltage in residentials 230Vac, but 50Hz ?
2)
The RCD which is also called FJ must (shall) trip also if there is no voltage available, poer standard requirement
How is this for the GFCI acc. UL 943
3)
where does the value 1.43 come from
4)
Where does the formula
20 over fault current in power 1.43
come from?

Thanks for your always perfect replies
Gustav
_____
Ich bin immer vorsichtig

 

[Lxnxjxhx]

Ich bin immer vorsichtig

Ich bin immer vorsichtig

Ich, nicht so viel.

People have a sensitivity to low level currents that, to be accurately modeled, should include time.

On the other hand, the electric chair puts out 2400vac and people in it get to experience 4 to 8 amps.

Also, public safety in the US is decided politically. A thousand people die every day from smoking related causes but if this same number died every day from plane crashes, "the roof would fall in" (pardon the idiom).
Baruch Fischoff has studied risk and the public's perception of it and he may "open your eyes."

Regards,
Herr "Long Year."

 

[dbuckley]

I wondered about this too. The European RCDs certainly are intended for people protection; when used for protecting things (like fire risk) 300mA trips were used.

I do recall a statement made some years ago that no-one had died from electrocution whilst protected by a 30mA RCD...

Here in NZ (and Oz) we're all 30mA as well....

 

[Lxnxjxhx]

GF levels

GF levels

we're all 30mA as well....

I think you're onto something.
Do you have AFCIs?

 

[Gustav]

Well oin most areas in Germany and other European countries we do not have any AFCIs we only use RCD's which shall work without any aux. power at a personell protection level of 30mA

 

[dbuckley]

Do you have AFCIs?

As far as I know, AFCIs are all American unique.