5 ms·

The ground contacts in Schuko plugs DO make contact first. It's just less obvious from the design I guess.

by ginko 5y ago

afiori 5y ago
In the uk plugs the ground contact also acts as a switch; you actually can use an europlug with the uk sockets but you need insert something in the ground pin anyway (some sockets simply a plastic pin instead of a connector)
- mytailorisrich 5y ago
  It does not act as a switch. The way it usually works, as mentioned by OJFord, is that wall sockets have safety shutters on the live and neutral connectors, which open when the earth pin is inserted in the earth connector in order to prevent a plug without earth from being connected. That's why sockets always have an earth pin even if only plastic on some cheap ones (for double insulated devices that do not require an earth connection). Pretty cool feature.
OJFord 5y ago
I'm aware, but Schuko != Europlug (despite being a plug used in many Euro countries), does not have shutters on the live/neutral opened by Earth contact, and (partly consequently) can often be trivially (mis)used not Earthing a device which should be.
- tremon 5y ago
  It isn't that trivial, as a device that should be earthed is not allowed to be sold with a Euro plug, they must have a Schuko plug. And likewise, an extension cord featuring Schuko sockets must have a Schuko plug, so there is officially no way to connect a Schuko device through a Euro plug. The real problem is with classic sockets as shown in [1]: these are two-pin (unearthed) sockets that can accept a Schuko plug nonetheless, and are widely used even in residential newbuilds, at least in NL. I think the building code has been updated now, but it's very common here to have entire rooms where the sockets don't even have a third wire in the wall box. [1] https://www.plugsocketmuseum.nl/ContEUR_part2.html https://www.plugsocketmuseum.nl/ContEUR_part2.html
  - OJFord 5y ago
    Thanks for the correction, think I'm confusing [1] (memories of France ~20 years ago, and old houses then) with Schuko.
  - jacquesm 5y ago
    Correct, new installations are required to carry ground to all sockets, but old systems are grandfathered in with the exception that if you upgrade one of the sockets in a room to grounded you have to do it for all of them. To get really pedantic: you are allowed to put a device that normally requires a safety ground into a non-grounded ('old style') outlet but then that circuit should have ground fault protection installed and conversely, if you have a circuit (such as for instance an oven) that does not have a ground fault protector you must use the ground. This covers a very large percentage of all normally occurring situations, though of course there will always be tricky ones due to rare combinations of devices and installation details. If you can play it safe: put ground fault protectors on all of your circuits except where leakage current is too high as a result of the consumers design and limit those to one consumer per circuit (dedicated circuit). This goes double for 'wet' spaces such as bathrooms, kitchens and so on, ground really is mandatory there from a safety perspective even if the code says it isn't, so if you still have ungrounded sockets in bathroom or kitchen add a ground if there is any reasonable way of doing so. In bathrooms the ground point can frequently be found behind the bathroom mirror over the sink. And don't be tempted to use the waterline, those are frequently made of plastic nowadays and no longer count as safety ground.
- jacquesm 5y ago
  Almost all of the sockets installed today have these shutters integrated, you need to put something synchronously into both neutral and live to get them to open.

The ground contacts in Schuko plugs DO make contact first. It's just less obvious from the design I guess.

by ginko 5y ago

The ground contacts in Schuko plugs DO make contact first. It's just less obvious from the design I guess.

In the uk plugs the ground contact also acts as a switch; you actually can use an europlug with the uk sockets but you need insert something in the ground pin anyway (some sockets simply a plastic pin instead of a connector)

mytailorisrich 5y ago
It does not act as a switch. The way it usually works, as mentioned by OJFord, is that wall sockets have safety shutters on the live and neutral connectors, which open when the earth pin is inserted in the earth connector in order to prevent a plug without earth from being connected. That's why sockets always have an earth pin even if only plastic on some cheap ones (for double insulated devices that do not require an earth connection). Pretty cool feature.

OJFord 5y ago

I'm aware, but Schuko != Europlug (despite being a plug used in many Euro countries), does not have shutters on the live/neutral opened by Earth contact, and (partly consequently) can often be trivially (mis)used not Earthing a device which should be.

tremon 5y ago
It isn't that trivial, as a device that should be earthed is not allowed to be sold with a Euro plug, they must have a Schuko plug. And likewise, an extension cord featuring Schuko sockets must have a Schuko plug, so there is officially no way to connect a Schuko device through a Euro plug. The real problem is with classic sockets as shown in [1]: these are two-pin (unearthed) sockets that can accept a Schuko plug nonetheless, and are widely used even in residential newbuilds, at least in NL. I think the building code has been updated now, but it's very common here to have entire rooms where the sockets don't even have a third wire in the wall box. [1] https://www.plugsocketmuseum.nl/ContEUR_part2.html https://www.plugsocketmuseum.nl/ContEUR_part2.html
- OJFord 5y ago
  Thanks for the correction, think I'm confusing [1] (memories of France ~20 years ago, and old houses then) with Schuko.
- jacquesm 5y ago
  Correct, new installations are required to carry ground to all sockets, but old systems are grandfathered in with the exception that if you upgrade one of the sockets in a room to grounded you have to do it for all of them. To get really pedantic: you are allowed to put a device that normally requires a safety ground into a non-grounded ('old style') outlet but then that circuit should have ground fault protection installed and conversely, if you have a circuit (such as for instance an oven) that does not have a ground fault protector you must use the ground. This covers a very large percentage of all normally occurring situations, though of course there will always be tricky ones due to rare combinations of devices and installation details. If you can play it safe: put ground fault protectors on all of your circuits except where leakage current is too high as a result of the consumers design and limit those to one consumer per circuit (dedicated circuit). This goes double for 'wet' spaces such as bathrooms, kitchens and so on, ground really is mandatory there from a safety perspective even if the code says it isn't, so if you still have ungrounded sockets in bathroom or kitchen add a ground if there is any reasonable way of doing so. In bathrooms the ground point can frequently be found behind the bathroom mirror over the sink. And don't be tempted to use the waterline, those are frequently made of plastic nowadays and no longer count as safety ground.
jacquesm 5y ago
Almost all of the sockets installed today have these shutters integrated, you need to put something synchronously into both neutral and live to get them to open.