Arc-Faults as Aluminum protection in Retrofit.

[glene77is]

Guys,
rt66electric had a post and asked a question to the effect of:

Would Arc-Fault Circuit Breakers be a cure-all for a residence
wired with Aluminum conductors ?

GFCI circuit breakers have been proposed in the past,
and covered by NEC.

Would Arc-Faults be a better choice ?

Opinions ?

 

[A/A Fuel GTX]

Guys,
rt66electric had a post and asked a question to the effect of:

Would Arc-Fault Circuit Breakers be a cure-all for a residence
wired with Aluminum conductors ?

GFCI circuit breakers have been proposed in the past,
and covered by NEC.

Would Arc-Faults be a better choice ?

Opinions ?

I wouldn't call anything a " cure all " but I would say arc fault breakers would be a good idea since they also provide 30 ma of ground fault protection if I remember correctly.

 

[cpal]

Guys,
GFCI circuit breakers have been proposed in the past,
and covered by NEC.

I am not sure what this statemnt is getting at??

are you suggesting that the NEC requires GFCI protection on aluminum conductors??

 

[petersonra]

Guys,
rt66electric had a post and asked a question to the effect of:

Would Arc-Fault Circuit Breakers be a cure-all for a residence
wired with Aluminum conductors ?

GFCI circuit breakers have been proposed in the past,
and covered by NEC.

Would Arc-Faults be a better choice ?

Opinions ?

The problem with smaller AL conductors used in residential wiring was corrosion related, not ground faults or arcing. I doubt it would make any real difference.

 

[Jim W in Tampa]

The problem with smaller AL conductors used in residential wiring was corrosion related, not ground faults or arcing. I doubt it would make any real difference.

But when the corrosion gets bad enough it will arc and just might prevent a fire.
Not a good fix but better than nothing.

 

[macmikeman]

I wonder if you can land aluminum wire right into the terminals of arc fault breakers without a copper pigtail. I haven't bothered to check that out myself yet.

 

[kwired]

I wonder if you can land aluminum wire right into the terminals of arc fault breakers without a copper pigtail. I haven't bothered to check that out myself yet.

Don't most of them have the same terminal device as standard breakers from the same product line? Most of them accept aluminum.

 

[kwired]

The problem with smaller AL conductors used in residential wiring was corrosion related, not ground faults or arcing. I doubt it would make any real difference.

The problem with small aluminum conductors is the fact that they expand and contract with temperature change faster than many other metals. Connections become loose from the expansion/contraction cycles and that introduces additional resistance and more heat making everything worse. Increased heating will also increase oxidation rate. Eventually there is a total failure of the connection.

The arcing that can occur in the loose connection is exactly one of the things AFCI is supposed to protect against. GFCI will not recognize this as anything abnormal - the current remains within the monitored path. Properly working GFCI's only trip when current does not flow through the monitored path at a level above their trip setting.

 

[glene77is]

I am not sure what this statemnt is getting at??
are you suggesting that the NEC requires GFCI protection on aluminum conductors??

CPAL,

NO.
During retrofits, this appears to be another option.
There is no cure for aluminum terminations or joints.
Comments ?

 

[glene77is]

The problem with small aluminum conductors is the fact that they expand and contract with temperature change faster than many other metals. Connections become loose from the expansion/contraction cycles and that introduces additional resistance and more heat making everything worse. Increased heating will also increase oxidation rate. Eventually there is a total failure of the connection.

KWired,
Agreed.

And the electrolysis effect between aluminum and copper
is a contributing factor. Aggravated by handling with sweaty fingers.

There is no real cure, especially since we all grab the freshly stripped aluminum wire with our sweaty fingers during stripping the insulation off.

I owned a house, years back, that was aluminum wired. :-?
I started replacing burned recepticals, repairing joints.
When I left that house, those nightmares stopped.

Comments on useing Arc-Fault CB as part of a retrofit program ?

 

[WinZip]

We just finished a home this week repairing each outlet with the 65 purple wire nuts an what a PITA , most boxes where small don't rem cu in size but you had to shape the joints in properly for the device to go in easily and something I will introduce to customers in the future is what I have read in this post and that is AFCI breakers with spliced copper but going to use a different device next time an not the 65 purple wire nuts, I don't trust them.

Will try these - http://www.alcopstore.com/

 

[don_resqcapt19]

...
The arcing that can occur in the loose connection is exactly one of the things AFCI is supposed to protect against. GFCI will not recognize this as anything abnormal - the current remains within the monitored path. Properly working GFCI's only trip when current does not flow through the monitored path at a level above their trip setting.

Yes, but even the new combination (series and parallel arcing fault detection) type AFCIs don't look at the arc signature until the current is above 5 amps. Currents much less that that can create enough heat to cause a fire. In many cases this undetected heating causes enough insulation damage to create a ground fault and the ground fault detection part of the AFCI will clear the fault.

 

[glene77is]

http://www.alcopstore.com/

Win,
AlCopStore King AlCu connectors work very well.
Very clean and set-screws are easy to tighten, with three holes.
Pigtail a copper out and just push the AL to the back.
Chester used $370 worth, and threw all the his Purples away.
They accept back any unopened bags.
So, be sure to ask for some of your count in the 25ct bags.

 

[kwired]

Yes, but even the new combination (series and parallel arcing fault detection) type AFCIs don't look at the arc signature until the current is above 5 amps. Currents much less that that can create enough heat to cause a fire. In many cases this undetected heating causes enough insulation damage to create a ground fault and the ground fault detection part of the AFCI will clear the fault.

Once again the controversy of what good is the AFCI is stirred up. I am not against the idea of AFCI's but feel there is room for a lot of improvement and they possibly should not be a requirement until some improvement is made. The manufacturers have tried hard to get them into code and now the users are the test lab.

 

[don_resqcapt19]

Once again the controversy of what good is the AFCI is stirred up. I am not against the idea of AFCI's but feel there is room for a lot of improvement and they possibly should not be a requirement until some improvement is made. The manufacturers have tried hard to get them into code and now the users are the test lab.

They even outright lied top get them into the code. The original proposals said they had a device that could do what the combination type AFCI is said to do....those proposals were some 13 years prior to the combination AFCI coming on the market.