Jordan of Artisan Electrics recently featured this failed circuit breaker from an electric vehicle charger. You can see that video here:-
https://www.youtube.com/watch?v=lW5vN1sUxI0
The unit is a combined overcurrent and leakage detection breaker - or RCBO (Residual Current Breaker with Overcurrent protection), which means it provides protection against short circuits and overcurrent as well as detection of AC and pulsing DC leakage. A normal AC leakage unit can't be used for EVs, due to the risk of a faulty charger leaking rectified AC that may not trip an ordinary breaker.
The construction is quite neat, with overcurrent on one side and leakage detection on the other.
The test resistor was hidden down a channel next to a terminal, and is rated 5000 ohms to give a trip test current of a fairly generous 45mA.
The leakage current mechanism is a magnetic latching type that triggers at 15mA by creating an opposing magnetic field to the holding magnetism, that releases the catch and allows it to fly open, striking the trip pin.
The circuitry is effectively a sense coil with diode voltage clamping and the trigger coil tapped across a capacitive divider to allow an element of trip current tuning and probably some filtering too.
The failure looks like typical circuit breaker failure. Very different contact arrangement to the previous one, but still the same failure point as in most standard breakers. Aside from the potential for unusual current waveforms associated with electronic loads, I wonder if atmospheric conditions also play a part due to the higher ambient humidity associated with outdoor equipment.
If you deal with EV (Electric Vehicle) charging pillars and experience breaker failures, let me know in the comments down below what brands are involved. It'll be interesting to see if this is a common issue amongst brands. Let me know if you also think my theory about the power factor correction current pulses being a contributing factor to the failure.
If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:-
http://www.bigclive.com/coffee.htm
This also keeps the channel independent of YouTube's advertising algorithms allowing it to be a bit more dangerous and naughty.
https://www.youtube.com/watch?v=lW5vN1sUxI0
The unit is a combined overcurrent and leakage detection breaker - or RCBO (Residual Current Breaker with Overcurrent protection), which means it provides protection against short circuits and overcurrent as well as detection of AC and pulsing DC leakage. A normal AC leakage unit can't be used for EVs, due to the risk of a faulty charger leaking rectified AC that may not trip an ordinary breaker.
The construction is quite neat, with overcurrent on one side and leakage detection on the other.
The test resistor was hidden down a channel next to a terminal, and is rated 5000 ohms to give a trip test current of a fairly generous 45mA.
The leakage current mechanism is a magnetic latching type that triggers at 15mA by creating an opposing magnetic field to the holding magnetism, that releases the catch and allows it to fly open, striking the trip pin.
The circuitry is effectively a sense coil with diode voltage clamping and the trigger coil tapped across a capacitive divider to allow an element of trip current tuning and probably some filtering too.
The failure looks like typical circuit breaker failure. Very different contact arrangement to the previous one, but still the same failure point as in most standard breakers. Aside from the potential for unusual current waveforms associated with electronic loads, I wonder if atmospheric conditions also play a part due to the higher ambient humidity associated with outdoor equipment.
If you deal with EV (Electric Vehicle) charging pillars and experience breaker failures, let me know in the comments down below what brands are involved. It'll be interesting to see if this is a common issue amongst brands. Let me know if you also think my theory about the power factor correction current pulses being a contributing factor to the failure.
If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:-
http://www.bigclive.com/coffee.htm
This also keeps the channel independent of YouTube's advertising algorithms allowing it to be a bit more dangerous and naughty.
Freudian slip eh Clive? 😂😂😂😅 Yes I caught it
"They're a bit sloppy so they can just……mate" – Big Clive 2020
Hehe, I also subscribe to Artisan Electrics. I'm a trained electrician from Germany and find it very interesting how things are done in other countries.
I am having a tethered 7.2KW Rolec installed but I will be dialling down my EV's internal charge rate controller to receive a maximum of 12 amps. The charge rate I choose will broadly match production from my solar PV system on the day. Would such a light load over a maximum 6 hours (two or three times a week) extend the life of the circuit-breaker, in your experience?
I was thinking of getting a Rolec charger installed on my Garage since my new electric car is due in a few months. Everyone on the EV forums basically said "no" and then I was linked this video (plus many, many pictures of exploded Rolecs). I don't exactly feel secure connecting a giant lithium bomb to one of these now…
well it's worse than my mains breaker not working as it should at all. when you press the little test button nothing happens……replaced it. i opened the thing but can't see any point of failure…
It’ll be ok, the damage is only on the side.
Never even heard of Rolec.
Sounds like a brand sold out of Aldi.
With an inductive load and high current you can get plasma arcing which still carries current and causes more damage. They have a spark quencher built in but it doesn’t look like the hot gasses can readily escape poor design
In the USA we have to use arc fault breaker’s in bedroom circuits. Are they similar to anything you guys use? My understanding is that they are different from GFCI breakers.
I will have you know I come here to watch you faff around, and then open the electronics and faff around some more.
did you want another burnt out rolec rcbo… I have one on the shelf!
Id be interested to know what Electric car this was charging in theory no EV should draw more than 32 amps AC as the cars on broad charger doesn't allow them to some EVs are only 16amps. However the Renault zoe is able on the Q motor to take much higher loads on a 3 phase supply it will happily go to 43kw. I've seen a zoe on a single phase draw over 7.6kw on some chargers for breif moments. Am currently reviewing EVERY EV charger in the UK Rolec still haven't sent me there unit for testing….
Would a C or D grade breaker work better with EV chargers? I assume they may have bigger contacts due to the higher loads they can withstand
👍👍
Very common . Absolute garbage rolec kit. They last about 6 months before they fail replaced loads of them
I did my EV course recently. On it was a bloke who worked for rolec in the past. According to him: 'They buy a container load of the cheapest Chinese breakers/RCDs they can and print a Rolec logo on them."
Uh, bigclive, the PFC’s role is precisely to “despike” the current and make the load behave like a resistor. With a PFC you should be getting a power factor very close to 1, and a high bandwidth (DC-100MHz at least) current probe should show a fairly clean line frequency waveform (50Hz in Europe). Maybe whatever the cheapened out EV chargers do is not PFC in spite of them claiming otherwise… how does that even make it to market in the supposedly regulation-obsessed Europe??