Smart Charger vs Commando Socket
Discussion
tendown said:
I agree with much of what has been posted that the likelihood of having a PEN fault and touching an earthed part of the car and being earthed to "real" earth is very slim.
However it "could" and probably does happen, although statistics aren't that easy to find other than some here and a very relevant and recent failed FOI here
This means by installing a non PEN protected commando socket for an EVSE having done the research about PEN faults you've made a conscious decision to save a few hundred quid to go against the recommendations/regulations. If the (however unlikely) worst happened it wouldn't look or feel good.
One of these or these makes it easy to add the recommended level of protection without the issues of earth rods.
Don't the charger bricks themselves achieve PEN protection from any fault on the secondary side of the brick? However it "could" and probably does happen, although statistics aren't that easy to find other than some here and a very relevant and recent failed FOI here
This means by installing a non PEN protected commando socket for an EVSE having done the research about PEN faults you've made a conscious decision to save a few hundred quid to go against the recommendations/regulations. If the (however unlikely) worst happened it wouldn't look or feel good.
One of these or these makes it easy to add the recommended level of protection without the issues of earth rods.
Even if not, if a spark is asked to install a commando socket outside or in a garage they only have to install it as per regs, without specifically taking in to account it's to be used for a car charger power lead - because it's just a socket. If a person installs their own commando socket and ends up harming or killing themselves due to a PEN fault, I expect they won't bother to show up at court to condemn themselves.
No ideas for a name said:
Not rubbishing anyone's product without full analysis, but it seems that the first of those clears the fault within 5s.
That if I read it right is seconds. Not milliseconds. Too late, game over.
As I understand them the regs say the device has to disconnect within 5s of a PEN fault occurring. So 5s after a fault it's protecting anyone who does the touching, rather than tripping at the time of touching, if you see what I mean....That if I read it right is seconds. Not milliseconds. Too late, game over.
TheDeuce said:
Don't the charger bricks themselves achieve PEN protection from any fault on the secondary side of the brick?
I don't know of any commando plugged EVSE units with PEN fault protection built it.TheDeuce said:
Even if not, if a spark is asked to install a commando socket outside or in a garage they only have to install it as per regs, without specifically taking in to account it's to be used for a car charger power lead - because it's just a socket. If a person installs their own commando socket and ends up harming or killing themselves due to a PEN fault, I expect they won't bother to show up at court to condemn themselves.
The point of my post was to counter the idea that you can save a few quid on EV chargers by using "just" a commando socket + EVSE. It doesn't really matter if the protections in the regulations don't work in every scenario, or if the chances of an issue is tiny. If someone other than yourself could access the car while charging - I don't think its worth saving the relatively small amount of money needed to be compliant, whether you're doing it DIY or getting a pro in for the certs and planning to tell them its definitely not for an EV.tendown said:
No ideas for a name said:
Not rubbishing anyone's product without full analysis, but it seems that the first of those clears the fault within 5s.
That if I read it right is seconds. Not milliseconds. Too late, game over.
As I understand them the regs say the device has to disconnect within 5s of a PEN fault occurring. So 5s after a fault it's protecting anyone who does the touching, rather than tripping at the time of touching, if you see what I mean....That if I read it right is seconds. Not milliseconds. Too late, game over.
However, since the units I have seen/read up on, don't seem to have any detection for welded contacts, it could well be that when you need it to operate, it doesn't. It is again a very very unlikely event, so obviously better than not having the device.
A test button and a check that the load was actually disconnected would do this.
Also, the devices seem to take their supply from the voltage being monitored - there are all sorts of potential (no pun) problems with this (most of which can be designed around however).
Gassing Station | EV and Alternative Fuels | Top of Page | What's New | My Stuff