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did a quick search and there is a post relating to it here :--

Don't know what the conclusion was or the success of any suggestions.
That literally sounds like rocket science to me! But thanks. :)


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That looks great thanks. I was wondering if there was a version where the supply to the whole pod point could be broken with a 32a WiFi switch rather than opening up the Pod-Point itself. I’m no electronics expert!


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This is a bad idea. You could end up switching off the podpoint whilst it's charging, breaking a 32amp current will cause arcing and sparks and possible damage to the electronics in the pod point or car.
The system is designed for the car or evse to signal its shutting down and allow the car to ramp down to zero before opening the contactor so preventing sparks etc.
 
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This is a bad idea. You could end up switching off the podpoint whilst it's charging, breaking a 32amp current will cause arcing and sparks and possible damage to the electronics in the pod point or car.
The system is designed for the car or evse to signal its shutting down and allow the car to ramp down to zero before opening the contactor so preventing sparks etc.
The wireless relay only makes\breaks the low ampage feed to the circuit breaker in the Rolec. Same as switching the rolec manually.
 

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The wireless relay only makes\breaks the low ampage feed to the circuit breaker in the Rolec. Same as switching the rolec manually.
You sure about that? For the reasons explained above, it's not healthy. It should be droppping the signal to the car that says power is available, then after a short delay it can trigger the breaker when there's no current flowing.
The breaker is for protection in an emergency, and not rated for breaking its rated current hundreds of times like a regular on-off switch.
 

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@baden I was replying to this question
This is a bad idea. You could end up switching off the podpoint whilst it's charging, breaking a 32amp current will cause arcing and sparks and possible damage to the electronics in the pod point or car.
The system is designed for the car or evse to signal its shutting down and allow the car to ramp down to zero before opening the contactor so preventing sparks etc.
Actually cutting the feed to the Contactor in the Rolec is as bad. You should switch the CP line - the correct circuit to do this was presented by @Jeremy Harris. The wifi switch goes in the CP line and switches in a resistance. This shuts down the charger in the car without trying to potentially to break a 32 Amp current flow.
 
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The wireless relay only makes\breaks the low ampage feed to the circuit breaker in the Rolec. Same as switching the rolec manually.

As above, this is absolutely not the way to do this safely. The protocol is specifically designed to ensure that, other than in a power cut, the charger (in the car) shuts down gracefully (remembering that it can present a pretty hefty reactive load) and then, and only then, does the charger signal to the charge point to break the mains power connection, when there is no current flowing. This prevents the possibility of the supply just being interrupted under full load, and so eliminates the risk that there may be a big spike as a consequence of a sudden disconnection. Not unknown for chargers to fail because of this, IIRC at least one member here has had that happen and the bill was potentially quite high, of the order of £1k or so for a replacement OBC.
 

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I have a version of the OpenEVSE firmware that can be installed on to the controller inside a Rolec charge point. It enables the serial port, which can be extended to work remotely over WiFi using something like an Elfin EW10.

Can both switch charging on and off and vary the charging current.

Like all of the solutions above, you still need something to manage the logic that decides when to switch on and off.
 

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Having ordered my Shelly 1 switch I'm still wondering about the connection. The current discussion is about putting the switch in the CP line. My BP Pulse is non-tethered and switched on/off using a key switch. The way I charge is connect cable to car-charger then switch on charger. I then turn the key to switch the charger on then wait whilst it checks its connected to the car then a green light to show charging. This light turns off when fully charged and I then turn the key off, unlock the car to remove the cable and drive off. Surely it would be better to bypass the key switch with the Shelly otherwise I will still need to unlock to switch the charger on.
 

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Switching it on is not the problem as the EVSE starts up, you see this when you turn on. Its the off that is the problem, currently you wait for charging to finish then turn off. Would you turn off whilst the car is charging? That breaking of the 32A current will cause arcing and may damage the car..
I doubt the keyswitch actually breaks the current as that would give the switch a very short life! It would be useful to find out just what the keyswitch controls. it may be the electronics and if your lucky does not really turn off the chargepoint but instructs the car to shutdown.
If it just turns off the evse, ie cuts power to the electronics then if the car is charging it opens the contactor with current flowing and will cause arcing.
 

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It's much more likely that the keyswitch does a low level change of signal on the CP line that tells the car to stop charging.

It's not clear whether the Shelly 1 uses an electromagnetic relay or a semiconductor device to do the switching. A semiconductor device might be safe to switch off as it will disconnect at a current zero crossing. The spec sheet and instruction sheet say nothing about maximum number of on/off cycles or what the switching element is.
In any case, if the Shelly is really designed and rated for repeated switching of a 3.5kW load it ought to work switching power to the EVSE, but it still strikes me as a rather crude way to do it.

Edited to add: I hope you only have a 16A charger because that's all the Shelly is rated for. Really don't try it on 32A!
 
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