Why does a "granny" charger for EV (<10A) not need an RCD?

[Julie.]

Thanks..
Though According to the following, the cause of DC leakage with EV's is insulation failure, coupled with the fact that there is a large DC battery in the EV...

It says nothing about DC leakage currents being more likely, the higher is the charge current...

New leakage current sensor for electric vehicle charging stations

The latest electronic component news from the world’s leading component distributors and manufacturers.

www.electropages.com

...so from the above, you would again have to ask, why dont granny chargers, that charge at 10A, need a DC leakage detection for >6mA DC leakage?

Well any electronic conversion of ac to dc will introduce harmonics back into the system due to the nonlinearity of the electronic rectifier - although dc is not strictly an harmonic it will be introduced, and you could do a Fourier analysis to calculate it.

 

[treezleef]

Well any electronic conversion of ac to dc will introduce harmonics back into the system due to the nonlinearity of the electronic rectifier - although dc is not strictly an harmonic it will be introduced, and you could do a Fourier analysis to calculate it.

Thanks, but that isnt the cause of the ">6mA DC leakage " that needs to be detected by the 16A EV chargers.

Also, the harmonics from SMPS's doesnt put any DC into the mains.

The >6mA DC leakage is due to insulation failure, and this is just as likely with a 10A charger as with a 16A charger, so why do 10A chargers not need ">6mA DC leakage detection"?

 

[telectrix]

surely the need for a RCD or not is dependent on granny's last will and testament. no point in electrocuting her if you're not included.

 

[littlespark]

We used to chuck grannies off buses. But we’ve been told not to as she’s our “mammies mammy”

 

[Zerax]

...so from the above, you would again have to ask, why dont granny chargers, that charge at 10A, need a DC leakage detection for >6mA DC leakage?

You need to re-read post #13...

 

[treezleef]

You need to re-read post #13...

A 'granny cable' or more correctly a Mode 2 charging cable will incorporate an In-cable Control Box (ICCB) that has RCD functionality.

thanks yes, but a granny charger does not have an RCD which is capable of measuring >6mA DC.

 

[Gavin John Hyde]

Good quality and new 'granny chargers' should have rcd protection of some sort built into them now.
seen some awful chinese ones that didnt have it mind. use at your own risk sort of stuff.

 

[treezleef]

..theabove video prooves that the granny chargers contain no ">6mA DC leakage" detection or protection.
So it seems surprising that EV chargers have to have it.

 

[Zerax]

thanks yes, but a granny charger does not have an RCD which is capable of measuring >6mA DC.

From Jan 2018 a Mode 2 cable ('granny cable') manufactured to BS EN62572 had to have >6mA DC fault protection.

btw... it's not a 'granny charger' it just supplies 230AC to the on-board charger.

 

[Julie.]

..theabove video prooves that the granny chargers contain no ">6mA DC leakage" detection or protection.
So it seems surprising that EV chargers have to have it.

No, it is probably legacy that these rubbish granny chargers do not.

Rcd and dc leakage are two seperate functions, they may be within the one device, in which case it is no longer an rcd it is a combined device.

You have to provide suitable protection on all equipment to disconnect in the case of a fault, ADS is not always sufficient, in which case RCD or equivalent protection is required. If you cannot rely on a standard RCD then you either need a special RCD or additional protection to disconnect.

It isn't a difficult concept.

 

[treezleef]

From Jan 2018 a Mode 2 cable ('granny cable') manufactured to BS EN62572 had to have >6mA DC fault protection.

btw... it's not a 'granny charger' it just supplies 230AC to the on-board charger.

Thanks,from 7:40 onwards, the efix experts are saying that "granny charge points" dont have ability to detect the >6mA DC. This video is from 2021....

 

[Julie.]

Thanks,from 7:40 onwards, the efix experts are saying that "granny charge points" dont have ability to detect the >6mA DC. This video is from 2021....

I have an old landrover from 1980, and that doesn't have the latest emissions limit introduced in 2018.

Why is it that the landrover group doesn't have to meet the emissions limits like other car manufacturers???

 

[treezleef]

Thanks, but it seems different.....car emissions is bad, but electric shock (so they say), is instant death. ...or so they say...(incidentally, having taken many full 240VAC mains across the chest, often with my pectoral muscles vibrating at 50Hz...i dont believe leccy is as bad as they say, but thats just me.)
The "powers" say that leccy is deadly....instantly so....so it seems odd that old granny charge points arent banned.
I have no idea how we can check if granny charge points do need >6mA detection, because most like me cant afford the standards.

 

[nicebutdim]

Thanks, but it seems different.....emissions is bad, but electric shock (so they say), is instant death. ...or so they say...having taken many full 240VAC mains across the chest, often with my pectoral muscles vibrating at 50Hz...i dont believe leccy is as bad as they say, but thats just me.
The "powers" say that leccy is deadly....instantly so.

Plenty of people might disagree if they weren't already dead from electrocution.

 

[DPG]

Thanks, but it seems different.....car emissions is bad, but electric shock (so they say), is instant death. ...or so they say...(incidentally, having taken many full 240VAC mains across the chest, often with my pectoral muscles vibrating at 50Hz...i dont believe leccy is as bad as they say, but thats just me.)
The "powers" say that leccy is deadly....instantly so....so it seems odd that old granny charge points arent banned.
I have no idea how we can check if granny charge points do need >6mA detection, because most like me cant afford the standards.

Dangerous attitude. Electricity can, and does, kill.