Fire risk of common NEMA 14-50 outlets
- Thread starter Will Prowse
- Start date
BarracudaBob
Harvesting free photons from clean fusion
Hubbell is what I went with. I'll avoid Leviton if I can. Hubbell is made in U.S.A. I can't tell from the picture where the Leviton is made.
BarracudaBob
Harvesting free photons from clean fusion
I believe the Amazon link was for a Hubble they aren't cheap but cheaper than burning your house down.
42OhmsPA
Who likes Electrical Gremlins?
Great thread.
I've been using the attached with an old "scrap" section of 6/3 since October. I'll have to shoot temps next time I'm dumping power into my Bolt for a long duration. I've ran the charger at 8 kW for hours on end, didn't feel anything getting warm but never checked with the IR.
@Supervstech Thank you for the info about GFCI breaker requirements...
I've been using the attached with an old "scrap" section of 6/3 since October. I'll have to shoot temps next time I'm dumping power into my Bolt for a long duration. I've ran the charger at 8 kW for hours on end, didn't feel anything getting warm but never checked with the IR.
@Supervstech Thank you for the info about GFCI breaker requirements...
Attachments
doing it different
Solar Enthusiast
A lot of Leviton stuff is made in USA (even their basic outlets and switches are). I usually use Leviton outlets and switches when I replace stuff in my house. Last time I used Legrand instead, and they're all made in China, and I don't like them all that much. Go figure. I'm a bit surprised/bummed that their 14-50R isn't so great but Hubbell is good stuff made in USA anyway.
Duh! Right right right.
dougbert
Solar Wizard
good question. under 3 hours, you can hit 50 amps
for over 3 hours 40 amps max (80% rule applies)
to get 48 amps for 3+ hours, then a hardware circuit on a 60 amp breaker is required
true
that is a NEMA 6-50r. the code of "6" is the 240v only specification and the "50" is for 50 amps. No need for 120v on EV chargers. On the NEMA 14-50r, the "14" specifies both 120v/240v present on the "r" receptacle. NEMA 14-50p is the plug side
I "believe" that is already a commercial quality unit. It is NOT the cheap receptacles we have been discussing. So I think you are good
zanydroid
Solar Wizard
L2 charging is 240V in the US. Last I checked 240V > 230V of other countries :laugh:
Also, wires / breakers can definitely feel warm if you size them to the max of 75C column. To the point of thermal tripping the breakers on a hot day (which actually means you didn't temp derate it enough with larger conductors)
NEMA outlets are pretty boomer, yeah. More like, Greatest Generation.
zanydroid
Solar Wizard
These? I dunno about it. I haven't taken one of these apart, but seen them in the store, and they scare me. Looks like for mobile homes, which has tendency of being... cutting edge in the wrong way (cheapest code compliant assembly)... with listed components.
zanydroid
Solar Wizard
IIRC welding circuits are allowed under NEC to have larger OCPD than the wire, because welding is very short blasts of electricity.
So you want to be extra diligent if someone else besides you installed the welding circuit. They might have availed of this dispensation. Or, just as likely, it was done by jimbo that just wanted to get their home workshop set up, and they applied whatever a random forum post from 1997 told them was safe.
So you want to be extra diligent if someone else besides you installed the welding circuit. They might have availed of this dispensation. Or, just as likely, it was done by jimbo that just wanted to get their home workshop set up, and they applied whatever a random forum post from 1997 told them was safe.
Pretty unlikely jimbob in 97 sought advice on any forum...
Diy bullitin boards were popular, but jimbob probably just winged it.
Maybe got advice from asking somebody...
Not to mention the blades are often not aligned to provide the increased contact area that would be expected on the thick wide blades.
Seen plenty where only a small point is the contact area.
If I have this right:
Apparently some of them check that the split-phase neutral is very close to exactly halfway between the two hots, in both voltage and phase, and refuse to charge if it is not.
I think this is intended to avoid setting things on fire if you have insufficient wiring, a bad joint, or a cheap-but-defective outlet B-) in the circuit, manifesting as voltage droop on one of the hot sides. (Apparently not all of them do this, or do it well enough, to prevent the melted-outlet fires.)
Unfortunately, high-frequency inverters do split phase by variants of two separate inverters, one for each hot, unlike a low-frequency inverter with an output transformer that's center-tapped. (These range from two output sections to two physical boxes on the wall trying to stay at the same voltage and 180 degree phase offset.) Keeping the voltages and phases matched well enough to satisfy the chargers - especially if there are unbalanced one-side loads also and the inverter is running near capacity - is problematic, leading to things like the notorious problems with e.g. Tesla charging from some house inverter systems.
Last edited:
dougbert
Solar Wizard
found this OP-ED on Reddit
See, other EV makers rented Teslas, had no idea why Tesla provided that kit, and copied them without thought, in full Cargo Cult manner, and without providing the full suite of alternative sockets for every other charging speed. And then, people get these things home that have ONLY a 15A/120V and 50A/240V plug. What do these novices very reasonably say?
"Well, therefore, level 2 must be 50A!"
/smh not even wrong. More cargo cult. But who corrects them?
On an RV, all loads are 120V so the RV can work at smaller "TT30" stands. So the neutral is very important there. But because of this very unfortunate misconception, EVers want to install 14-50s also, and the socket must have neutral in case someone plugs in an RV. So there we are wasting money on neutrals.
So instead of 12/2 to a wall unit, easy peasy... they spend *actually more* on costly GFCI breaker to costly 6/3 cable to a costly Hubbell socket.
And don't forget that $4000 service upgrade. With some wall units, you can do Load Management so the EV charging has no impact on the service at all.
So how is that asshat? Because of what they did think about/fixate on. They wanted to make 14-30 and 14-50 be similar enough that sockets could use the same brass parts internally. And yes, one manufacturer offers a 14-30-50 socket with two plastic faceplates, and you install the L-shaped neutral if you want 14-30, or the I-shaped 14-50 neutral. FRICKING GOLF CLAP.
Why NEMA 14-50 instead of 6-50 for EV charging?
TLDR: Because a confluence of stupidity.
Long answer: early EVs were shipped with "Travel Units" meant to be kept in the trunk and used for opportunity charging on the road. Now which useful sockets are found on the road?- The common one (NEMA 5-15): lousy but everywhere.
- The 14-50 RV socket found at RV parks, the best place to get big power on the road.
See, other EV makers rented Teslas, had no idea why Tesla provided that kit, and copied them without thought, in full Cargo Cult manner, and without providing the full suite of alternative sockets for every other charging speed. And then, people get these things home that have ONLY a 15A/120V and 50A/240V plug. What do these novices very reasonably say?
"Well, therefore, level 2 must be 50A!"
/smh not even wrong. More cargo cult. But who corrects them?
On an RV, all loads are 120V so the RV can work at smaller "TT30" stands. So the neutral is very important there. But because of this very unfortunate misconception, EVers want to install 14-50s also, and the socket must have neutral in case someone plugs in an RV. So there we are wasting money on neutrals.
And remember. All this is in pursuit of "cheap".
The cheapness is that the EV novice wants to use the provided "travel unit" instead of paying money for a wall unit, that would be much more versatile. The wall unit could be a) hardwired, avoiding a Hubbell socket and GFCI, and b) detuned to a more sensible charge rate like 12-16 amps @ 240V (3-4 kW) appropriate for every-night charging at home. And that 12-16A circuit is much, much easier to provision into a home, without any need for $4000 service upgrade.So instead of 12/2 to a wall unit, easy peasy... they spend *actually more* on costly GFCI breaker to costly 6/3 cable to a costly Hubbell socket.
And don't forget that $4000 service upgrade. With some wall units, you can do Load Management so the EV charging has no impact on the service at all.
But why 14-50 and not 6-50?
Yet more people in the parade of asshats. When NEMA was initially defining 6-30 (!), 14-30, 6-50 and 14-50... they didn't even think about making the 6-50 be supercompatible with the 14-50 (so that 6-50 plugs would work in 14-50 sockets). Nor 6-30 plugs in 14-30 sockets - the concept never entered their minds. Had they done that, EV travel units would have shipped with 6-50 of course.So how is that asshat? Because of what they did think about/fixate on. They wanted to make 14-30 and 14-50 be similar enough that sockets could use the same brass parts internally. And yes, one manufacturer offers a 14-30-50 socket with two plastic faceplates, and you install the L-shaped neutral if you want 14-30, or the I-shaped 14-50 neutral. FRICKING GOLF CLAP.
sunshine_eggo
Victron's little biatch
Or if good you skip the neutral pin and the 14-xx plug fits both the dryer outlet (30A) and the RV park (50A)
dougbert
Solar Wizard
doh! great ideaOr if good you skip the neutral pin and the 14-xx plug fits both the dryer outlet (30A) and the RV park (50A)
dougbert
Solar Wizard
many places grid is pushing 245 to 247 volts now. most NEMA 240v plugs and receptacles are rated for 250V
Example, looking at picture in post #52 it shows 125/250v
L1 is 230 in many other countries.
I had an electrician (family member) come out to resolve an issue with a house outlet that was zapping me. He resolved that and I asked him about my EV circuit. While we were there talking about the EV circuit he installed the Hubbell 14-50R. His opinion is that the Leviton outlet was the root cause of the overheating and the existing wire (he checked that it was real copper) should be fine.
It will get a test soon!
It will get a test soon!
I'm in the middle of the first charge of my EV using the Hubbell outlet. It's cool as a cucumber! By this point in the charge the charger's plug as well as the outlet and the nearby conduit would be warm and they're not at all warm. The EV's state of charge was below 40% so the charger should have been charging as hard as it could.
I am overjoyed with this result!
I am overjoyed with this result!
Similar threads
