TXjak
Owner/Investor/Advocate
So it sounds like a breaker defect. Perhaps this has been fixed in the newer breakers?
-
Want to remove ads? Register an account and login to see fewer ads, and become a Supporting Member to remove almost all ads.
Extending/Converting exisiting Nema 10-30R to Nema 14-50R
- Thread starter Hometheatremaven
- Start date
I have an existing subpanel that may connect before the main breaker panel. It is much newer than the Zinsco box. Maybe I could use it; somehow reroute the old dryer wires to it.
I'll do some research as to it's specs and let you know what it is.
I guess I'd still be limited as to Amps by the existing aluminum wire gauge going to the dryer outlet.
I'll do some research as to it's specs and let you know what it is.
I guess I'd still be limited as to Amps by the existing aluminum wire gauge going to the dryer outlet.
No, the ENTIRE SYSTEM is defective. The buss bars are designed such that no matter how you design the breaker, they cannot avoid the potential of failure.
This is why most insurance companies will not insure a home with a Zinsco or FPE panel. The whole SYSTEM is faulty.
- - - Updated - - -
You won't be permitted to touch that existing dryer circuit or its wiring without invalidating code compliance for the NEMA 10-30; it'll have to be replaced with a 6-30 or 14-30, and you'll have to run a ground to it. Your best bet is to install a new 50A circuit if you can off a panel that doesn't draw power from that Zinsco.
Whatever you do, it's critical that you not use one of those 30-to-50 adapter cords if it runs through that Zinsco. I will reiterate one final time that if you do use one of those cords and your house catches fire, regardless of whether it has anything to do with the cord/car or not, it's highly likely you won't be compensated for your loss, and you'll be out both your home and car.
One final plea, then I'll stop because I've said it enough: please invest the $2k or so it takes to ensure the safety of you and your family by replacing that Zinsco.
EDIT: one final bit of advice on extending that circuit - if you do - wherever you have aluminum wire joining copper wire, you must use special connectors rated for connecting the two, or they will quickly corrode and break apart, causing a fire hazard. Extending that outlet by using a home-made plug-wire-and-receptacle can be an insurance problem because it's not UL listed as an extension cord, and as permanent wiring it doesn't comply with NEC. The only way to properly extend that circuit would be to eliminate the current receptacle, extend the wiring to where you need it, run a ground as required, and install a NEMA 14-30, all compliant with the NEC. Note that a neutral / white wire cannot be repurposed as an equipment safety ground (in case you want to change the 10-30 to a 6-30). Any ground wires smaller than #8 MUST be green, green with yellow stripe, or bare.
Last edited:
FlasherZ:
1. If I do this to extend the circuit 30 feet. should I use 10/3 with ground or 8/3 with ground?
2. What is the difference between A: "eliminating the current (10-30) receptacle" to extend the circuit and B: just buying a 10-30 plug and connecting it with the above wire (#1) to a 14-30R, making sure the 14-30R is properly grounded to a cold water supply pipe I have? (I know I can't use the neutral as a ground).
I understand your concern if I terminate with a 14-50R and a software update overrides my 30A charging setting. Am I correct in assuming if I use the 14-30 Tesla adapter on the Mobile Connector, the Tesla won't try and charge at 40A?
Thanks again for your valuable and expert advise. I know you are thinking of our best interest, but every house in my area was built around 1969, probably with the Zinsco box, and none have burned down yet. I did experience a problem once with a connection between a copper pigtail from a breaker to the aluminum house wiring. But all that happened was the joint corroded and wouldn't pass power. I trimmed the joint and coated it with Noalox and it's fine now.
P.S. I have a friend whose son is an electrician. I think he's going to come over next week. The more information I have, the better I can discuss this intelligently with him.
1. If I do this to extend the circuit 30 feet. should I use 10/3 with ground or 8/3 with ground?
2. What is the difference between A: "eliminating the current (10-30) receptacle" to extend the circuit and B: just buying a 10-30 plug and connecting it with the above wire (#1) to a 14-30R, making sure the 14-30R is properly grounded to a cold water supply pipe I have? (I know I can't use the neutral as a ground).
I understand your concern if I terminate with a 14-50R and a software update overrides my 30A charging setting. Am I correct in assuming if I use the 14-30 Tesla adapter on the Mobile Connector, the Tesla won't try and charge at 40A?
Thanks again for your valuable and expert advise. I know you are thinking of our best interest, but every house in my area was built around 1969, probably with the Zinsco box, and none have burned down yet. I did experience a problem once with a connection between a copper pigtail from a breaker to the aluminum house wiring. But all that happened was the joint corroded and wouldn't pass power. I trimmed the joint and coated it with Noalox and it's fine now.
P.S. I have a friend whose son is an electrician. I think he's going to come over next week. The more information I have, the better I can discuss this intelligently with him.
10/3 is fine for a 24A load on a 30A circuit up to 200' one-way from the service panel.
A) eliminates the "extension cord" aspects and will require you to do electrical construction per the NEC to deliver the receptacle to the final spot where the UMC plugs into the NEMA 14-30.
B) effectively uses an "extension cord", to use a comparison with standard 120V 5-15 outlets. NEC governs the code compliance for the electrical construction to the existing NEMA 10-30 receptacle (which I understand to be code compliant as existing installation), then you would need an appropriate, UL-listed/rated extension/adapter cord to provide your NEMA 14-30. By constructing one with a 10-30P to a 14-30R, you've created an extension cord.
The NEC contains some rules for using extension cords. Some of the rules state that extension cords are not permitted to be used as a substitute for the fixed wiring of a structure; run through holes in walls, structural ceilings, suspended ceilings, dropped ceilings, or floors; run through doorways, windows, or similar openings; or be concealed behind building walls, structural ceilings, suspended ceilings, dropped ceilings, or floors.
Correct. If you use a 30A adapter on the MC, it will charge at 24A maximum.
I personally experienced an FPE panel failure in my California rental home in 1997 that nearly burned it, due to a breaker's failure to trip. It was a combination of failures: a crimp-splice (common in the 1960's and 1970's) had failed, creating a higher-resistance point which generated heat when an appliance was run (in my case, a microwave oven and some lighting), eventually creating a bigger, lower-resistance short when the insulation melted from the wires. The breaker failed to trip, causing the reaction to continue at extremely high currents, turning the entire circuit into a giant heater in my wall. I was probably an hour from seeing the house catch fire. I was lucky to be home and awake when it gave way or I would have lost everything.
I should also note that every house in my neighborhood (as it sounds yours is) was built in typical California "pattern-home" style, and they had not experienced any major fires that I was aware of while living there. Mine was the first in my neighborhood.
FPE and Zinsco panel failures are common and have a high rate of occurrence -- just search for them... Moreover, the type of failure that can happen is the worst type -- a breaker that trips once while testing (giving you some sense of security) may permanently jam and fail to trip again. With FPE and Zinsco panels, you really don't know when the failure will occur, but we do know that they have very high failure rates and there is a reason most insurance companies will refuse to cover a home with an FPE or Zinsco panel when they find out. There is a reason that Solar City refused to do that install for you. Hopefully your friend's son will be able to explain it to you as well.
A simple question: knowing that Zinsco panels are inherently dangerous, have many, MANY catalogged failures, why would you not replace it at the first possible moment? These are not "if it ain't broke, don't fix it" scenarios, because they are broke by default.
Last edited:
strider
Active Member
So I'm sitting here reading your post and I think to myself, "Hey, I live in a California house that was built in 1967." So I walk out into my garage and open my panel. Federal Pacific Electric Corporation, Newark, NJ. -<whee>-
So many homes were built with FPE Stab-Lok panels, it's really a shame.
After re-reading the OP's reply, another thought came to mind that is important to note: these are secondary failures. The reason you have circuit breakers is to provide protection in case of a primary fault. FPE and Zinsco panels don't cause fires by themselves, but rather they are intended to keep fires from happening -- and they don't do that. Another, primary, fault needs to occur before they become dangerous -- like my crimp splice, or a "back-stabbed" outlet (one of those where you push the wires in instead of use the screws) that gets loose, or an appliance that malfunctions and shorts a hot wire to the frame, or a car that tries to draw 40A through an adapter cord and circuit intended for 24A...
It's the primary reason I'm against using these adapter cables, "even if" you make sure the circuit breakers work, "even if" you make sure the car is set to 24A, "even if"... You're buying a $60k+ car: if you can't afford up to $2-3k for electrical work to support that while ensuring your life safety, you should not be purchasing the car.
Last edited:
Firstly, the car is about $90K after options. Secondly, I can assure you I can afford the new box.
I will see what the electrician has to say and then I'll decide what to do.
You need not insult me anymore. Thanks for all your help.
spatterso911
P100DL - Raven
I may be speaking out of turn here, and Im replying on behalf of a fellow poster, but I don't see an insult there, and I'm fairly certain that FlasherZ doesn't imply one in it. It's just that its well known that the minimum cost of the car is $60k+ and that a large number of people are stretching budgets to put this car in the garage, mainly because it is a phenomenal car and worth the budget stretch. His main concern is one of the safety of your family and a desire to prevent people from making drastic mistakes in compromise electrical solutions. He has posted many times in the past on this issue and given his personal experience, is passionate about it. I would take his advice seriously, given that you aren't limited in your choices. Hopefully, the electrician agrees with what he is saying.
I absolutely agree with you. FlasherZ has been a great help in explaining things for me and others.
He is a tremendous asset to this board.
I think I can make an informed decision after talking with the electrician.
It may not be the decision FlasherZ so fervently espouses. Then again, it may be.
Fortunately, I am able to afford a new box.
He is a tremendous asset to this board.
I think I can make an informed decision after talking with the electrician.
It may not be the decision FlasherZ so fervently espouses. Then again, it may be.
Fortunately, I am able to afford a new box.
No insult intended at all. It's precisely what I would say to my own mother if in the same circumstances. Zinsco and FPE panels are known to be killer devices. If it's a trade-off between the car and life safety, focus on safety now and wait 6-12 months for the car. If it's not an affordability trade-off, then there is no other choice, period: save you and your family's life now and enjoy the car.
The only other alternative is, IMO, criminal negligence. That's not hyperbole, it's simply the unvarnished truth.
Outside of another electrician's opinion, if you have full confidence in your panel, then I might recommend calling your homeowner's insurance company. Let them know that you have heard concerns about Zinsco circuit breaker panels because you have one, and ask them if they take a position on it from an insurance point of view.
I will not be angry that you choose not to take my advice, I just want you to be informed just how much of a ticking time bomb those things are. You've already heard from a licensed electrician (Solar City's subcontractor) and someone with direct personal experience with one of these failures (me). I can only hope you take that into consideration in addition to your friend's son's comments.
Some further reading:
Zinsco Damage
Wikipedia: Zinsco
Failure rate of 10-15%
Video of a Zinsco breaker failing under test
The only other alternative is, IMO, criminal negligence. That's not hyperbole, it's simply the unvarnished truth.
Outside of another electrician's opinion, if you have full confidence in your panel, then I might recommend calling your homeowner's insurance company. Let them know that you have heard concerns about Zinsco circuit breaker panels because you have one, and ask them if they take a position on it from an insurance point of view.
I will not be angry that you choose not to take my advice, I just want you to be informed just how much of a ticking time bomb those things are. You've already heard from a licensed electrician (Solar City's subcontractor) and someone with direct personal experience with one of these failures (me). I can only hope you take that into consideration in addition to your friend's son's comments.
Some further reading:
Zinsco Damage
Wikipedia: Zinsco
Failure rate of 10-15%
Video of a Zinsco breaker failing under test
Last edited:
FlasherZ is right on the money with this observation.
Imagine, for a moment, how the press will react when they get to report on the first house fire and fatality caused by an electric car charging station installed in a house. It will be far more damaging than Fisker fires and other related problems.
And, imagine what will happen with installation inspections and the cost of house/auto insurance that involve electric vehicles.
Unfortunately, as the installed base of electric vehicles increases and the cost of those vehicles comes down, the people that install electric vehicle charging stations in violation of codes and with obsolete and dangerous components (e.g., electric distribution panels) will increase.
People on this web site are fortunate to have knowledge and experience available from people like FlasherZ.
mknox
Well-Known Member
For a significant part of my 34+ year career in the electric utility business, I managed a group of Inspectors who's job was to ensure a safe installation before we'd energize a new or upgraded service (this was done separately from but in cooperation with the Provincial safety authority responsible for behind the meter wiring). FlasherZ is correct, and I think that with this knowledge, one should really think carefully about how to proceed.
This is not about the "bad press", it is about property damage and potential loss of life. Sorry, but maybe I've been exposed to and seen too many tragedies caused by faulty electrical wiring and equipment, but I really do believe "Safety First".
Hometheatremaven, who did you call at Tesla about the 10-30 adapter? This would be perfect for when I am visiting my folks, who have a 10-30 socket in their garage. I asked about it when talking with one of the service advisors at the Menlo Park service center, and he said it is not available. Thanks.
I've been asking for it for 2 months. As of today, I'm told "No update on the 14-30. We are still awaiting word from the factory. So far, they have not provided a timeline at all."
Really had the same answer. Just a general "we expect them soon" As far as I know, none of the other adapters (10-30 and 14-30) are available at this time.
I'm hoping they get them approved and ready by Spring. My Tesla S should be delivered April-May.
Read the original post and said to myself: "Unless this house is in So FL, So TX, So Az or So CA, take this opportunity to rip the walls apart room by room starting where the breaker box is located. Don't touch the existing wiring at all, just install an entirely new system. You can also upgrade the insulation and even some plumbing. New CATV, home audio, phone lines, etc. All this will increase the value of the home greatly. And you can sleep soundly at night.
But you are in the: "USA". (??).
--
But you are in the: "USA". (??).
--
Horrible Housing market?Just curious (it's not obvious to me), why do you list those jurisdictions? Seems like that's where you could get it done sooner.
- - - Updated - - -
Horrible Housing market?Just curious (it's not obvious to me), why do you list those jurisdictions? Seems like that's where you could get it done sooner.
> Just curious (it's not obvious to me), why do you list those jurisdictions? [FlasherZ]
If a house has Al wiring, that certainly implies that its insulation is also still at the late 70s quality level. So rather than waste time & energy trying to do a minimally invasive snaking & fishing job with the cable replacement chore, you could chose to rip the walls completely out in order to put in new insulation, new wiring, new sheetrock, new paint. Your life could become a sitcom. :biggrin:
Down in the tropical zone = less incentive.
--
If a house has Al wiring, that certainly implies that its insulation is also still at the late 70s quality level. So rather than waste time & energy trying to do a minimally invasive snaking & fishing job with the cable replacement chore, you could chose to rip the walls completely out in order to put in new insulation, new wiring, new sheetrock, new paint. Your life could become a sitcom. :biggrin:
Down in the tropical zone = less incentive.
--
Similar threads
