Charging - can someone explain it?

[TheDeuce]

pghstochaj said:

TheDeuce said:

Anything that comes with a pre fitted plug must confirm to whatever safety standards it needs to when plugged in to any regulation meeting socket.

I am sure the "charger" and cable does, no doubt in that, but that doesn't mean the system overall does. That is, the manufacturer of the "charger" is not responsible for making sure you have adequate safety features on the 3-pin socket being used.

I had a bit of a google on this out of interest this morning, I will do a bit more searching but as far as I can see, the "charger" primarily has features to tell the car it can charge, not that it has appropriate RCD protection (or 6 mA DC leakage detection) or suitable earthing system/earth fault detection.

It doesn't matter what specific features it has or does not have. It has a fitted plug which means it is designed and tested as fully safe for use when plugged in to any correctly installated household socket.

Obviously the socket is itself protected at very least by a suitable MCB as per regs.

[48k]

TheDeuce said:

48k said:

pghstochaj said:

For people that use a 3 pin plug, do you not have the necessary safety requirements normally required for the “chargers” (correct rcd or 6 mA dc leakage detection, appropriate earthing or Earth fault detection) or do these features sit within the “granny charger”?

The granny charger will have a box of tricks in it which takes car of monitoring but obviously can't govern what circuit you plug it in to.

Also true. Specifically it can't create an earth if the socket isn't earthed... But then the socket wouldn't meet regs anyway so is an issue regardless of what you plug in to it.

Earth is one scenario. I was thinking more about the circuit itself - a hard-wired charging station is on a dedicated circuit and it's direct to the car, whereas you could plug the granny charger in to any old ring where it's going to be left on for hours and you might have fan heater, drills etc. all trying to pull from the same circuit. or you may be plugging in to an extension lead to reach the car if the car is outside of the garage. The manual for my XC40 recharge pitches the granny charger as a "last resort" charging option and warns to never use it with an extension lead, multiple plug socket or other adapters. I'm sure other manufacturers will have similar warnings. It doesn't bother me as I don't use the granny charger but those warnings will be there for a reason.

[pghstochaj]

TheDeuce said:

pghstochaj said:

TheDeuce said:

Anything that comes with a pre fitted plug must confirm to whatever safety standards it needs to when plugged in to any regulation meeting socket.

I am sure the "charger" and cable does, no doubt in that, but that doesn't mean the system overall does. That is, the manufacturer of the "charger" is not responsible for making sure you have adequate safety features on the 3-pin socket being used.

I had a bit of a google on this out of interest this morning, I will do a bit more searching but as far as I can see, the "charger" primarily has features to tell the car it can charge, not that it has appropriate RCD protection (or 6 mA DC leakage detection) or suitable earthing system/earth fault detection.

It doesn't matter what specific features it has or does not have. It has a fitted plug which means it is designed and tested as fully safe for use when plugged in to any correctly installated household socket.

Obviously the socket is itself protected at very least by a suitable MCB as per regs.

What's a "correctly installed household socket"? What regulation requires a device that you plug into a 3-pin socket to be safe as long as you have a "correctly installed household socket"? The safety requirements for a socket vary depending on their usage and a manufacturer selling you (for example) a lawn mower cannot take responsibility for you using it from a socket without an RCD.

Why would the socket be protected by a suitable MCB? Fuses are still allowed to be used and what about RCD protection?

[TheDeuce]

48k said:

TheDeuce said:

48k said:

pghstochaj said:

For people that use a 3 pin plug, do you not have the necessary safety requirements normally required for the “chargers” (correct rcd or 6 mA dc leakage detection, appropriate earthing or Earth fault detection) or do these features sit within the “granny charger”?

The granny charger will have a box of tricks in it which takes car of monitoring but obviously can't govern what circuit you plug it in to.

Also true. Specifically it can't create an earth if the socket isn't earthed... But then the socket wouldn't meet regs anyway so is an issue regardless of what you plug in to it.

Earth is one scenario. I was thinking more about the circuit itself - a hard-wired charging station is on a dedicated circuit and it's direct to the car, whereas you could plug the granny charger in to any old ring where it's going to be left on for hours and you might have fan heater, drills etc. all trying to pull from the same circuit. or you may be plugging in to an extension lead to reach the car. The manual for my XC40 recharge pitches the granny charger as a "last resort" charging option and warns to never use it with an extension lead, multiple plug socket or other adapters. I'm sure other manufacturers will have similar warnings. It doesn't bother me as I don't use the granny charger but I'm sure those warnings must be there for a reason.

They definitely are there for a reason but also on all sorts of other appliances. There's nothing particularly special about a granny charger that requires more caution than anything else with a plug.

You can overload a 32a RFC by plugging in too many of any sort of electrical item... And you can overload an extension lead of you plug anything in to it that exceeds it's amp rating - which is displayed on the extension lead...

[essayer]

I think the 'granny' usually incorporates overheat protection at the plug end, so if the socket overheats it stops charging

Maybe it monitors L/N and trips on imbalance?

But after the socket, you're on your own. How good is your outside socket's supply, is there a RCD anywhere, is it spurred off a ring main which someone accidentally turned into a radial 20 years ago..?

[TheDeuce]

pghstochaj said:

TheDeuce said:

pghstochaj said:

TheDeuce said:

Anything that comes with a pre fitted plug must confirm to whatever safety standards it needs to when plugged in to any regulation meeting socket.

I am sure the "charger" and cable does, no doubt in that, but that doesn't mean the system overall does. That is, the manufacturer of the "charger" is not responsible for making sure you have adequate safety features on the 3-pin socket being used.

I had a bit of a google on this out of interest this morning, I will do a bit more searching but as far as I can see, the "charger" primarily has features to tell the car it can charge, not that it has appropriate RCD protection (or 6 mA DC leakage detection) or suitable earthing system/earth fault detection.

It doesn't matter what specific features it has or does not have. It has a fitted plug which means it is designed and tested as fully safe for use when plugged in to any correctly installated household socket.

Obviously the socket is itself protected at very least by a suitable MCB as per regs.

What's a "correctly installed household socket"? What regulation requires a device that you plug into a 3-pin socket to be safe as long as you have a "correctly installed household socket"? The safety requirements for a socket vary depending on their usage and a manufacturer selling you (for example) a lawn mower cannot take responsibility for you using it from a socket without an RCD.

Why would the socket be protected by a suitable MCB? Fuses are still allowed to be used and what about RCD protection?

I nearly typed 'or fuse' but does it really need saying!? Yes, a legally installed socket has suitable circuit protection. It may not have additional rcd protection which in some cases is required - for example, sockets installed near external doors in case someone plugs in a lawnmower or charger etc..

Strictly speaking anything used outdoors should only be plugged in to an rcd protected socket of via an rcd plug. Clearly that's often not the case but it's not overtly dangerous in the case of the charger is it? Lawnmowers are a different case as it's so easy to slice the cord. The granny charger however won't even deliver current until the plug is locked in the the cars charging port.

I don't understand why you're questioning these things tbh. There is absolutely nothing inherent to granny chargers that represents a greater risk than endless other appliances most households have and use outdoors

Edited by TheDeuce on Monday 29th November 12:36

[pghstochaj]

TheDeuce said:

pghstochaj said:

TheDeuce said:

pghstochaj said:

TheDeuce said:

Anything that comes with a pre fitted plug must confirm to whatever safety standards it needs to when plugged in to any regulation meeting socket.

I am sure the "charger" and cable does, no doubt in that, but that doesn't mean the system overall does. That is, the manufacturer of the "charger" is not responsible for making sure you have adequate safety features on the 3-pin socket being used.

I had a bit of a google on this out of interest this morning, I will do a bit more searching but as far as I can see, the "charger" primarily has features to tell the car it can charge, not that it has appropriate RCD protection (or 6 mA DC leakage detection) or suitable earthing system/earth fault detection.

It doesn't matter what specific features it has or does not have. It has a fitted plug which means it is designed and tested as fully safe for use when plugged in to any correctly installated household socket.

Obviously the socket is itself protected at very least by a suitable MCB as per regs.

What's a "correctly installed household socket"? What regulation requires a device that you plug into a 3-pin socket to be safe as long as you have a "correctly installed household socket"? The safety requirements for a socket vary depending on their usage and a manufacturer selling you (for example) a lawn mower cannot take responsibility for you using it from a socket without an RCD.

Why would the socket be protected by a suitable MCB? Fuses are still allowed to be used and what about RCD protection?

I nearly typed 'or fuse' but does it really need saying!? Yes, a legally installed socket has suitable circuit protection. It may not have additional rcd protection which in some cases is required - for example, sockets installed near external doors in case someone plugs in a lawnmower or charger etc..

Strictly speaking anything used outdoors should only be plugged in to an rcd protected socket of via an rcd plug. Clearly that's often not the case but it's not overtly dangerous in the case of the charger is it? Lawnmowers are a different case as it's so easy to slice the cord. The granny charger however won't even deliver current until the plug is locked in the the cars charging port.

I don't understand why you're questioning these things tbh. There is absolutely nothing inherent to granny chargers that represents a greater risk than endless other appliances most households have and use outdoors

Edited by TheDeuce on Monday 29th November 12:36

I am questioning it because it is my feeling that "Granny Chargers" are used without sufficient safety precautions in place.

There's no such thing as a legally installed socket, a socket installed in the 1960s met the regulations at the time but would not meet the regulations today. The socket installed today might be safe to use, the socket installed then might not be. It just depends on how they have been specified. Both are "legal".

Not the "Granny charger" itself - what it is connected to. I have no doubt that the "Granny Charger" is safe at all times. I am sure that the "Granny Charger" has a CE mark or UKCA mark and complies with the Electrical Equipment (Safety) Regulations 1994. It's introducing the car that changes the hazard and risk.

For example:

I am not aware of electric lawn mowers creating DC leakage to blind type A RCDs?
I am not aware of any electric lawn mowers that are not double insulated and therefore they would not normally need PEN fault detection.

There's a reason why these regulations are in place for mode 3 chargers and I am interested to figure out why people think they are not required for a mode 2 charger.

Edit: It is worth pointing out that other items such as hot tubs with risks more like an EV car have TT earthing rather than using the PME from the house, so some items are treated differently.

Edited by pghstochaj on Monday 29th November 12:57

[pghstochaj]

Seems well covered here (both DC leakage and PEN faults):

https://www.speakev.com/threads/granny-charger-pen...

[TheDeuce]

pghstochaj said:

TheDeuce said:

pghstochaj said:

TheDeuce said:

pghstochaj said:

TheDeuce said:

Anything that comes with a pre fitted plug must confirm to whatever safety standards it needs to when plugged in to any regulation meeting socket.

I am sure the "charger" and cable does, no doubt in that, but that doesn't mean the system overall does. That is, the manufacturer of the "charger" is not responsible for making sure you have adequate safety features on the 3-pin socket being used.

I had a bit of a google on this out of interest this morning, I will do a bit more searching but as far as I can see, the "charger" primarily has features to tell the car it can charge, not that it has appropriate RCD protection (or 6 mA DC leakage detection) or suitable earthing system/earth fault detection.

It doesn't matter what specific features it has or does not have. It has a fitted plug which means it is designed and tested as fully safe for use when plugged in to any correctly installated household socket.

Obviously the socket is itself protected at very least by a suitable MCB as per regs.

What's a "correctly installed household socket"? What regulation requires a device that you plug into a 3-pin socket to be safe as long as you have a "correctly installed household socket"? The safety requirements for a socket vary depending on their usage and a manufacturer selling you (for example) a lawn mower cannot take responsibility for you using it from a socket without an RCD.

Why would the socket be protected by a suitable MCB? Fuses are still allowed to be used and what about RCD protection?

I nearly typed 'or fuse' but does it really need saying!? Yes, a legally installed socket has suitable circuit protection. It may not have additional rcd protection which in some cases is required - for example, sockets installed near external doors in case someone plugs in a lawnmower or charger etc..

Strictly speaking anything used outdoors should only be plugged in to an rcd protected socket of via an rcd plug. Clearly that's often not the case but it's not overtly dangerous in the case of the charger is it? Lawnmowers are a different case as it's so easy to slice the cord. The granny charger however won't even deliver current until the plug is locked in the the cars charging port.

I don't understand why you're questioning these things tbh. There is absolutely nothing inherent to granny chargers that represents a greater risk than endless other appliances most households have and use outdoors

Edited by TheDeuce on Monday 29th November 12:36

I am questioning it because it is my feeling that "Granny Chargers" are used without sufficient safety precautions in place.

There's no such thing as a legally installed socket, a socket installed in the 1960s met the regulations at the time but would not meet the regulations today. The socket installed today might be safe to use, the socket installed then might not be. It just depends on how they have been specified. Both are "legal".

Not the "Granny charger" itself - what it is connected to. I have no doubt that the "Granny Charger" is safe at all times. I am sure that the "Granny Charger" has a CE mark or UKCA mark and complies with the Electrical Equipment (Safety) Regulations 1994. It's introducing the car that changes the hazard and risk.

For example:

I am not aware of electric lawn mowers creating DC leakage to blind type A RCDs?
I am not aware of any electric lawn mowers that are not double insulated and therefore they would not normally need PEN fault detection.

There's a reason why these regulations are in place for mode 3 chargers and I am interested to figure out why people think they are not required for a mode 2 charger.

Edit: It is worth pointing out that other items such as hot tubs with risks more like an EV car have TT earthing rather than using the PME from the house, so some items are treated differently.

Edited by pghstochaj on Monday 29th November 12:57

A hot tub isn't supplied with a 13a plug though.. so naturally the installer is forced to think about the power connection.

All chargers, including the granny chargers feature fault detection on the load side, including, on mine at least, leak protection. Because of the ELV communication between the car and the charger, high voltage current won't be delivered if there is any fault detected either end.

Regards DC leakage.. How would that get back to the charger? The charger is AC to the actual charger in the car which converts to DC (I think)

[pghstochaj]

TheDeuce said:

pghstochaj said:

TheDeuce said:

pghstochaj said:

TheDeuce said:

pghstochaj said:

TheDeuce said:

Anything that comes with a pre fitted plug must confirm to whatever safety standards it needs to when plugged in to any regulation meeting socket.

I am sure the "charger" and cable does, no doubt in that, but that doesn't mean the system overall does. That is, the manufacturer of the "charger" is not responsible for making sure you have adequate safety features on the 3-pin socket being used.

I had a bit of a google on this out of interest this morning, I will do a bit more searching but as far as I can see, the "charger" primarily has features to tell the car it can charge, not that it has appropriate RCD protection (or 6 mA DC leakage detection) or suitable earthing system/earth fault detection.

It doesn't matter what specific features it has or does not have. It has a fitted plug which means it is designed and tested as fully safe for use when plugged in to any correctly installated household socket.

Obviously the socket is itself protected at very least by a suitable MCB as per regs.

What's a "correctly installed household socket"? What regulation requires a device that you plug into a 3-pin socket to be safe as long as you have a "correctly installed household socket"? The safety requirements for a socket vary depending on their usage and a manufacturer selling you (for example) a lawn mower cannot take responsibility for you using it from a socket without an RCD.

Why would the socket be protected by a suitable MCB? Fuses are still allowed to be used and what about RCD protection?

I nearly typed 'or fuse' but does it really need saying!? Yes, a legally installed socket has suitable circuit protection. It may not have additional rcd protection which in some cases is required - for example, sockets installed near external doors in case someone plugs in a lawnmower or charger etc..

Strictly speaking anything used outdoors should only be plugged in to an rcd protected socket of via an rcd plug. Clearly that's often not the case but it's not overtly dangerous in the case of the charger is it? Lawnmowers are a different case as it's so easy to slice the cord. The granny charger however won't even deliver current until the plug is locked in the the cars charging port.

I don't understand why you're questioning these things tbh. There is absolutely nothing inherent to granny chargers that represents a greater risk than endless other appliances most households have and use outdoors

Edited by TheDeuce on Monday 29th November 12:36

I am questioning it because it is my feeling that "Granny Chargers" are used without sufficient safety precautions in place.

There's no such thing as a legally installed socket, a socket installed in the 1960s met the regulations at the time but would not meet the regulations today. The socket installed today might be safe to use, the socket installed then might not be. It just depends on how they have been specified. Both are "legal".

Not the "Granny charger" itself - what it is connected to. I have no doubt that the "Granny Charger" is safe at all times. I am sure that the "Granny Charger" has a CE mark or UKCA mark and complies with the Electrical Equipment (Safety) Regulations 1994. It's introducing the car that changes the hazard and risk.

For example:

I am not aware of electric lawn mowers creating DC leakage to blind type A RCDs?
I am not aware of any electric lawn mowers that are not double insulated and therefore they would not normally need PEN fault detection.

There's a reason why these regulations are in place for mode 3 chargers and I am interested to figure out why people think they are not required for a mode 2 charger.

Edit: It is worth pointing out that other items such as hot tubs with risks more like an EV car have TT earthing rather than using the PME from the house, so some items are treated differently.

Edited by pghstochaj on Monday 29th November 12:57

A hot tub isn't supplied with a 13a plug though.. so naturally the installer is forced to think about the power connection.

All chargers, including the granny chargers feature fault detection on the load side, including, on mine at least, leak protection. Because of the ELV communication between the car and the charger, high voltage current won't be delivered if there is any fault detected either end.

Regards DC leakage.. How would that get back to the charger? The charger is AC to the actual charger in the car which converts to DC (I think)

Being forced to think about the power connection is exactly what is being discussed here, or the lack of that thought process because the device is simply plugged in. It doesn't change the physics behind earthing.

I think when you say "leak detection" you mean for water leaks, I can't find any that have DC leakage detection and it would be a big assumption that "leak detection" is DC leakage detection. I am not an electrical engineer so I cannot tell you how the DC leakage works back through the charger, but it can which is why Type B RCDs are required, or 6 mA DC leakage detection.

I have no doubt that the "Granny Charger" doesn't have a check for faults and only allows voltage and then current once it has checked the faults. The question here is whether the "Granny Charger" is checking for PEN fault (or suitable earthing) or DC leakage. I don't think they are.

[TheDeuce]

pghstochaj said:

TheDeuce said:

pghstochaj said:

TheDeuce said:

pghstochaj said:

TheDeuce said:

pghstochaj said:

TheDeuce said:

Anything that comes with a pre fitted plug must confirm to whatever safety standards it needs to when plugged in to any regulation meeting socket.

I am sure the "charger" and cable does, no doubt in that, but that doesn't mean the system overall does. That is, the manufacturer of the "charger" is not responsible for making sure you have adequate safety features on the 3-pin socket being used.

I had a bit of a google on this out of interest this morning, I will do a bit more searching but as far as I can see, the "charger" primarily has features to tell the car it can charge, not that it has appropriate RCD protection (or 6 mA DC leakage detection) or suitable earthing system/earth fault detection.

It doesn't matter what specific features it has or does not have. It has a fitted plug which means it is designed and tested as fully safe for use when plugged in to any correctly installated household socket.

Obviously the socket is itself protected at very least by a suitable MCB as per regs.

What's a "correctly installed household socket"? What regulation requires a device that you plug into a 3-pin socket to be safe as long as you have a "correctly installed household socket"? The safety requirements for a socket vary depending on their usage and a manufacturer selling you (for example) a lawn mower cannot take responsibility for you using it from a socket without an RCD.

Why would the socket be protected by a suitable MCB? Fuses are still allowed to be used and what about RCD protection?

I nearly typed 'or fuse' but does it really need saying!? Yes, a legally installed socket has suitable circuit protection. It may not have additional rcd protection which in some cases is required - for example, sockets installed near external doors in case someone plugs in a lawnmower or charger etc..

Strictly speaking anything used outdoors should only be plugged in to an rcd protected socket of via an rcd plug. Clearly that's often not the case but it's not overtly dangerous in the case of the charger is it? Lawnmowers are a different case as it's so easy to slice the cord. The granny charger however won't even deliver current until the plug is locked in the the cars charging port.

I don't understand why you're questioning these things tbh. There is absolutely nothing inherent to granny chargers that represents a greater risk than endless other appliances most households have and use outdoors

Edited by TheDeuce on Monday 29th November 12:36

I am questioning it because it is my feeling that "Granny Chargers" are used without sufficient safety precautions in place.

There's no such thing as a legally installed socket, a socket installed in the 1960s met the regulations at the time but would not meet the regulations today. The socket installed today might be safe to use, the socket installed then might not be. It just depends on how they have been specified. Both are "legal".

Not the "Granny charger" itself - what it is connected to. I have no doubt that the "Granny Charger" is safe at all times. I am sure that the "Granny Charger" has a CE mark or UKCA mark and complies with the Electrical Equipment (Safety) Regulations 1994. It's introducing the car that changes the hazard and risk.

For example:

I am not aware of electric lawn mowers creating DC leakage to blind type A RCDs?
I am not aware of any electric lawn mowers that are not double insulated and therefore they would not normally need PEN fault detection.

There's a reason why these regulations are in place for mode 3 chargers and I am interested to figure out why people think they are not required for a mode 2 charger.

Edit: It is worth pointing out that other items such as hot tubs with risks more like an EV car have TT earthing rather than using the PME from the house, so some items are treated differently.

Edited by pghstochaj on Monday 29th November 12:57

A hot tub isn't supplied with a 13a plug though.. so naturally the installer is forced to think about the power connection.

All chargers, including the granny chargers feature fault detection on the load side, including, on mine at least, leak protection. Because of the ELV communication between the car and the charger, high voltage current won't be delivered if there is any fault detected either end.

Regards DC leakage.. How would that get back to the charger? The charger is AC to the actual charger in the car which converts to DC (I think)

Being forced to think about the power connection is exactly what is being discussed here, or the lack of that thought process because the device is simply plugged in. It doesn't change the physics behind earthing.

I think when you say "leak detection" you mean for water leaks, I can't find any that have DC leakage detection and it would be a big assumption that "leak detection" is DC leakage detection. I am not an electrical engineer so I cannot tell you how the DC leakage works back through the charger, but it can which is why Type B RCDs are required, or 6 mA DC leakage detection.

I have no doubt that the "Granny Charger" doesn't have a check for faults and only allows voltage and then current once it has checked the faults. The question here is whether the "Granny Charger" is checking for PEN fault (or suitable earthing) or DC leakage. I don't think they are.

I don't have any problem believing that the granny charger can detect any unusual current. DC or otherwise - it's just not that hard to do. Yes, if you create a dedicated circuit for a permanently installed charger you use a suitable rcbo to provide protection over and above a standard rcd. Some chargers may stipulate type b, depending on what inbuilt current detection hardware they have on board.

The granny charger requires only that it be plugged in to an rcd protected socket - which obviously often won't be the case - but that is all that the manufacturer says so clearly they believe basic rcd protection is sufficient. I think that fact suggests there is current leak detection present within the charger itself.

[TheDeuce]

This is the RCBO that protects my 7kw wall charger: https://www.rselectricalsupplies.co.uk/rolec-40a-c...

Note it is type C, not B

There is no other protection to the circuit.

[No ideas for a name]

Interesting disciussion. Some poor assumptions that can affect people's safety.

Though not exactly the same as it uses a 'Commando' plug rather than a 13A plug, but the notes for electricians are quite clear what the Ohme charger (for instance) does.

It does have a Type A (that is Type A not curve A) RDC and 6mA DC detection.
Recommendation is that any socket intended for charge points intended to charge a vehicle outdoors, should have TT earthing (an earth rod) or some other device that can detect open circuit PEN.

Personally I wouldn't be having a socket used for EV supply that wasn't TT earthed.
Lots of things you can 'get away with' and most of the time it will be fine... that once when there is a broken neutral on the DNO side and it could cause you a big problem. Rare but it happens, and you have no protection against it if you just use an 'ordinary' socket.

(Edited for spelling)

Edited by No ideas for a name on Monday 29th November 14:09

[TheDeuce]

No ideas for a name said:

Interesting disciussion. Some poor assumptions that can affect people's safety.

Though not exactly the same as it uses a 'Comando' ply rather than a 13A plug, but the notes for electricians are quite clear what the Ohme charger (for instance) does.

It does have a Type A (that is Type A not curve A) RDC and 6mA DC detection.
Recommendation is that any socket intended for charge points intended to charge a vehicle outdoors, should have TT earthing (an earth rod) or some other device that can detect open circuit PEN.

Personally I wouldn't be having a socket used for EV supply that wasn't TT earthed.
Lots of things you can 'get away with' and most of the time it will be fine... that once when there is a broken neutral on the DNO side and it could cause you a big problem. Rare but it happens, and you have no protection against it if you just use an 'ordinary' socket.

Lets say a person has a typical outdoor socket installed, and duly the installer ensures its protected via MCB+RCD of RCBO, the house holder then plugs un their mower, strimmer whatever... All fairly normal.

But then if one day they start using the socket to plug their granny charger in to, you believe the socket should be protected differently and have it's own earth too. Why? What is it about the granny charger that you think represents the additional risk?

NOTE: I would understand if they socket was being used to directly deliver current to a battery, but that is not the case with EV charging.

[pghstochaj]

TheDeuce said:

No ideas for a name said:

Interesting disciussion. Some poor assumptions that can affect people's safety.

Though not exactly the same as it uses a 'Comando' ply rather than a 13A plug, but the notes for electricians are quite clear what the Ohme charger (for instance) does.

It does have a Type A (that is Type A not curve A) RDC and 6mA DC detection.
Recommendation is that any socket intended for charge points intended to charge a vehicle outdoors, should have TT earthing (an earth rod) or some other device that can detect open circuit PEN.

Personally I wouldn't be having a socket used for EV supply that wasn't TT earthed.
Lots of things you can 'get away with' and most of the time it will be fine... that once when there is a broken neutral on the DNO side and it could cause you a big problem. Rare but it happens, and you have no protection against it if you just use an 'ordinary' socket.

Lets say a person has a typical outdoor socket installed, and duly the installer ensures its protected via MCB+RCD of RCBO, the house holder then plugs un their mower, strimmer whatever... All fairly normal.

But then if one day they start using the socket to plug their granny charger in to, you believe the socket should be protected differently and have it's own earth too. Why? What is it about the granny charger that you think represents the additional risk?

NOTE: I would understand if they socket was being used to directly deliver current to a battery, but that is not the case with EV charging.

Because the car is not double insulated and therefore a PEN fault could result in electrocution. This is not possible with a double insulated lawn mower.
Because the lawn mower does not create DC leakage through its charging system and therefore will not blind the RCD hiding an earth leakage fault.

[No ideas for a name]

pghstochaj said:

Because the car is not double insulated and therefore a PEN fault could result in electrocution. This is not possible with a double insulated lawn mower.
Because the lawn mower does not create DC leakage through its charging system and therefore will not blind the RCD hiding an earth leakage fault.

This.

[pghstochaj]

TheDeuce said:

This is the RCBO that protects my 7kw wall charger: https://www.rselectricalsupplies.co.uk/rolec-40a-c...

Note it is type C, not B

There is no other protection to the circuit.

That's not a type C RCBO, no such thing exists. It is a Type A RCBO with C curve tripping characteristics (that is for current). It is sensitive to DC leakage and therefore would not trip in the event of DC leakage from the car. This hasn't complied with the Regulations (without additional DC leakage detection) for years now (2019?).

Type C just dictates how long it takes for the MCB part of the RBCO to react on over current.

[No ideas for a name]

Simple 'lab' simulation...

If you had say a 3kW heater (so a reasonable resistive load) plugged in to your supply. and nothing else (for simplicity)
If the neutral incommer gets broken on the DNO side...
Your heater would go off and you go to investigate...
Your combined neutral/earth is now lifted to near live potential (240V) due to the pull-up through the heater element.
If you now touch your earthed appliance, yow take 240 through your body down to true earth.
RCB *may* not trip as there may not be significant imbalance between L and N.

[pghstochaj]

TheDeuce said:

I don't have any problem believing that the granny charger can detect any unusual current. DC or otherwise - it's just not that hard to do. Yes, if you create a dedicated circuit for a permanently installed charger you use a suitable rcbo to provide protection over and above a standard rcd. Some chargers may stipulate type b, depending on what inbuilt current detection hardware they have on board.

The granny charger requires only that it be plugged in to an rcd protected socket - which obviously often won't be the case - but that is all that the manufacturer says so clearly they believe basic rcd protection is sufficient. I think that fact suggests there is current leak detection present within the charger itself.

Nor do I, it's a fairly cheap facility to add, I just don't think that any "Granny Chargers" have the feature, I certainly think its extremely dangerous to assume "leakage detection" equates to DC leakage detection.

I think you need to move away from thinking this is about current, a type A RCD can be used if you have a means to detect DC leakage and stop charging (e.g. Podpoint) but otherwise a type B RCD is required.

The Granny Charger can be plugged into any 3-pin socket and work, the question is whether it is safe and compliant with the Regulations to do so. It is not up to the cable or cable manufacturer to inspect your house wiring system and consumer unit to determine if it is safe.

I remain interested to determine whether the Regulations apply to "Granny Chargers" and if not, why not. That will need me to read 18th edition amendments I guess.

[48k]

Interesting discussion. As a non electrician - very educational. Question for the electricians - would it be reasonable to assume that the manufacturer supplied OEM granny charger that comes with the car meets the regulations or does the electric shock risk still exist? Given the regulations around type approval and construction and use regulations on car the itself - is it naïve to assume that any OEM kit provided with the car is of similar quality ?

For reference this is the consumer unit in my garage which is fed directly from the meter (not from the main house consumer unit). The EVSE charger on the outside garage wall is on the "EV" circuit, and I have two separate circuits for the garage sockets. So are people saying there is a risk of electric shock plugging the granny charger in to one of the sockets in the garage?