Be careful presenting examples like I do.
Infinity might compare you to a dog chasing his tail.....
JAP>
AFCI required on MWBC?
- Thread starter jaggedben
- Start date
- Status
Be careful presenting examples like I do.
Infinity might compare you to a dog chasing his tail.....
JAP>
oldsparky52
Senior Member
- Location
- Wilmington, NC USA
jaggedben
Senior Member
- Location
- Northern California
- Occupation
- Solar and Energy Storage Installer
Folks, overcurrent was and is irrelevant to the topic.
oldsparky52
Senior Member
- Location
- Wilmington, NC USA
oldsparky52
Senior Member
- Location
- Wilmington, NC USA
This whole topic seems irrelevant seeing as how there hasn't been an answer that everyone will agree on.
JAP>
jaggedben
Senior Member
- Location
- Northern California
- Occupation
- Solar and Energy Storage Installer
That doesn't mean it hasn't given me useful information.
I'd like to get back to which brands produce multi-pole breakers that won't trip on certain systems.
No one makes a 3-pole AFCI, right? (Probably just no market and they'll say 'use 3-wire circuits in dwellings.')
If one wants to use a 2-pole AFCI on a 3 wire MWBC, will it work on a 120/208 circuit? Or does it depend on the brand?
One cannot use single pole AFCIs with handle ties .... unless they don't have GFCI functionality? (Which breaker would you land the neutral on?) Does anyone besides GE make these?
oldsparky52
Senior Member
- Location
- Wilmington, NC USA
That would make me want to use GE.
How is GE's "nuisance" tripping record as compared to other manufacturers?
wwhitney
Senior Member
- Location
- Berkeley, CA
- Occupation
- Retired
wwhitney
Senior Member
- Location
- Berkeley, CA
- Occupation
- Retired
The relevancy is that the phrase "overcurrent device protecting the circuit" appears in the definition of Branch Circuit.
Cheers, Wayne
oldsparky52
Senior Member
- Location
- Wilmington, NC USA
That may have been what you meant, but I don't think it's what you wrote (at least not the way I understood you).
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
Have you ever measured the voltage of the derived "third phase" of a rotary phase converter? It is never even close to same volts to neutral as the input conductors.In that case, there's your AFCI workaround: get a large rotary phase converter and run all your circuits from a 3 phase panel.
Seriously, with a GE or BR panel, there are AFCIs without GF detection, so you could run a 3-phase MWBC for 120V loads with 3 single pole AFCI breakers and a handle tie. [I'm assuming that GE or BR make a 3-phase panel that accepts those breakers.]
Cheers, Wayne
GE and BR three phase panels I would assume accept an AFCI breaker with no problems, do they make a three pole handle tie though?
LarryFine
Master Electrician Electric Contractor Richmond VA
- Location
- Henrico County, VA
- Occupation
- Electrical Contractor
But, as a delta source, they're relatively close.
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
Rotary phase converter line to line voltages are definitely better than what you usually see from a static converter. Somewhat is dependent on connected load in either case.
al hildenbrand
Senior Member
- Location
- Minnesota
- Occupation
- Electrical Contractor, Electrical Consultant, Electrical Engineer
That is correct. No manufacture sells a common trip 3-pole combination-type AFCI.
Sq D's 2-pole combination-type AFCI installation instructions clearly state the breaker is NOT to be installed on 208 / 120 V 3-wire single phase.
I'm not in possession of current Eaton and Siemen 2-pole combination-type AFCI installation instructions, so I can't comment about their compatibility with 208 / 120 V 3-wire single phase.
GE does not make a 2-pole AFCI, at all, because there is no need for it, given the capabilities of the GE single-pole AFCI.
This is true for Siemens, Sq D and Eaton CH breakers.
The Eaton BR combination-type AFCI, even though it has no ground fault sensing component, still requires the branch circuit load neutral to be landed on the breaker load neutral terminal; and there are no Eaton BR handle tie instructions.
NOTE the Exception is GE combination-type AFCI single pole breakers THAT CAN BE handle tied.
GE combination-type AFCI single pole breakers are allowed to be installed WITHOUT the load neutral landing on any of the handle tied breakers.
NO.
Eaton's BR type AFCI is close, but the required landing of the LOAD neutral on the breaker is different from the GE simplicity of not using the LOAD neutral at all.
- Status