ADVICE NEEDED: fish smell from house circuit board when car charges

From my experience and what I have read, the Kona EV on a L2 EVSE is limited to 32 amps or 7.4 kw. That is what my Grizzl-e EVSE is set to and I have not smelled any fish. My circuit breaker is 50amps.

 

You've certainly provided more info (other than location) than many other requests for help on this forum but the fish issue really does seem like an electrical problem in your home. It's not possible for the Kona to pull more than 32-ish amps and it's little different from any other load in the house.

I'm sure @electriceddy will be along at any moment to provide more enlightened commentary but the electrician needs to check the wiring and neutral-ground bonding more carefully. But as best as I'm aware it's the charger that cares more about those points than the car.

You can reduce the Kona's current at the dash using either the "minimum" or "reduced" station charging settings, if that would help narrow down the problem. You can also set the ChargePoint to 16 amps which does essentially the same thing.

 

That smell *could* indicate some small rodent has expired in a wall cavity. Heavy current draw generates heat, which could warm the remains.

 

Nahhh... OP already said the circuit breaker on the switch board was burnt out. It's an electrical problem, not a biological one.

 

I have to say my Wallbox wall box gets quite warm and the region around the 40 amp breaker gets warm too even though it's only pulling 32amps. I'm presuming this is normal. The wiring for my setup was specifically run from the meter and sized for high amperage workshop and EV charging.
It does sound like the OP has a wiring issue.

 

What is the brand of your panel?
What do the cables look like at the breaker?
Electrician shouldn't care what it connected to the load at all - the issue is in the panel. If there was an overcurrent causing excessive heat that's the breaker's job to prevent.

It sounds like the bus bar in your panel is bad and is overheating the breaker due to I^2R losses (it doesn't take a lot of resistance to burn up a connection at 32 amps

 

Coincidentally, Munro Live just posted a video regarding Home Charging Installation Risks.

 

Certainly that could be what's happened, heating at the circuit breaker screw termination or the buss connection. The OP's charger is hardwired so there's no low-quality NEMA outlet to worry about. It does seem surprising that these components are out on the market yet can't support well under their rated load.

 

The spot(s) on the panel bus bars should be checked out too. If the old breaker was arcing there due
to a loose clip where it connects, the bus bar itself might be burnt and distorted. A new breaker
might only get screwed up in short order by that poor feed contact. Moving the breaker to a different
slot might be an interim fix.

_H*

 

When I think about the issues raised by Munro with the NEMA outlet and circuit breaker, it's clear to me that the problem may arise where a set screw clamp is made directly on stranded wires, or the set screw is accompanied by a plate to effect a parallel-acting clamp. The wire strands are ductile and need a more circumferential clamp that applies an even radial compressive force on the bundle. The set screw works onto a small area and will not be able to maintain tension over a long period, as in years. A parallel clamp partly relies on the strands not unwinding under pressure. Neither have much springiness to help maintain contact.

Much is said about the plug and receptacle contact resistance increasing with repeated use but I suspect problems in that area are less common. Those parts are designed specifically to maintain continuous contact pressure and the materials are selected to have suitable properties.

The EV itself has no such issues because all connections are machine-crimped circumferentially to controlled dimensions. Related plug and socket connections are similarly made to high standards, and despite sitting for years undisturbed, don't exhibit issues. Industry is full of electrical connection examples that work just fine.

This could be more a failure of the relevant domestic N. American electrical standards, product design and quality control, that EVs have simply brought to the surface due to the essentially-continuous loading.

Tests I did some time ago when I found one 10A AU/NZ extension cord plug getting warmer than the others indicated the problem was from a poor quality crimp buried inside the molded plug. These were made of material that was probably too thin, not crimped in a controlled manner and then soldered as well, which alters the material characteristics. Heat generated by the resistance of the soldered joint can't easily escape through the plastic so travels both up the copper wire and down the plug pin. But the latter has only a physically small contact to the receptacle and can't conduct much heat out. Heat going up the wire adds to the warming already present due to wire resistance, so the cord gets warmer near the plug.
I measured the actual pin and socket electrical resistance and found no problems with that, all were 4.4 milliohm.

 

See, OP just needed an experienced electrician!

The Munro video is interesting because as usual Sandy talks the most but knows the least, and manages to continually present a facial expression that could sink a ship. I'm glad that the two other guys at least had a high level of technical knowledge, if not that much specific to the subject discussed.

My impression of the evidence presented is that none of those are likely to have actually started a house fire. They all failed in the intended manner, even though it looks gruesome.

 

Usually overheating electrical connectors create an acrid small of burning plastics.

I had an annoying "fish" smell when a poor electrical lighting connector was overheating in the ceiling and charring some cellulose type of roof insulation.
I looked up the specifications of the old flaked cellulose and it had originally been treated with fire retardant and blown into the ceiling cavity, swamping electrical cables. Apparently this was a cheap method in Australia and worked well for about 6 months

 

What is the New Zealand house wiring standard supply?

 

I never trust pre-molded plug/socket heads on high-current extension cables. I always lop them off
and install real ones [or multi-outlet boxes with spec-grade outlets] for anything I'm serious about.

If you tighten a connection onto copper and go back a while later to apply a steady torque onto the
screw and hold that for a few seconds, the screw *will* move more in that direction as the copper
settles into its new constraint. Very good to pay attention to in things like breaker panels.

_H*

 

230VAC 50Hz single phase at often just 60A with neutral bonded to ground at the main panel. All very simple and a wall-mounted home charger would be hard-wired, mostly to minimise cost. We don't normally have the customary fitment of a heavy-duty outlet in the garage and kitchen as common in N.A. Electric ranges can have a 32A receptacle but electric clothes dryers just run off a normal 10A outlet.

 

I would suggest that there is something wrong with the ground wire either in the house electrical panel, or in the connection to your EV charger (the ChargePoint). The fried breaker strongly indicates that there is a grounding problem specific to the charger circuit. (And yes, I know it isn't technically an "EV charger", but I can't remember the alternate word.)

 

I think the OP has probably had their problem fixed and has disappeared into the ether.

 

EVSE