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Faulty charger - Replace the components with OpenEVSE?

Hi all, I have a NewMotion Home Fast that is just under 3 years old and has stopped charging my car (in the UK). I've opened it up but there is nothing obviously wrong with it and the panel doesn't give me any useful logs or messages as to the problem (I also don't like this device as it has no timed charging and gives limited information). The manufacturer is being difficult so I'm working on the assumption I'll need to replace it, so I'm wondering if I can just replace the internal components with an OpenEVSE kit or individual components.

The existing set up has a supplemental earthing rod and is protected by and 40A RCD/MCB as per the photo. The unit is capable of 3-phase although I don't make use of that - max current is 7.4Kw @ 240v.

The installation contactor is an ABB ESB40-40N. Given the cost of these, if possible I would like to reuse this.


1. Is this feasible/sensible? (I appreciate I could buy the whole kit with a case but I don't want to throw parts away if not required.)

2. Can I reuse this contactor?

3. The existing ABB Contactor looks like it is controlled by 230v - Does the OpenOVSE also use 230v for the control circuit? I can't find it in the specs, although one of the contactors for sale also uses 230v for the control so I assume it's compatible.

4. There are two white wires which enter the "EH-04 auxiliary contact block" and connect on the PCB, but I cannot see the purpose of these and they are not labeled in the installation guide. Any idea what are they for? 

5. Just out of interest in the existing set up the 3 phase wires and Neutral also connect to the PCB. Any clue as to why this might be? Some sort of monitoring? I note that the OpenEVSE board does not do this (although there are two connections AC_TEST 1 & 2).

6. There is an existing Ground Fault Measurement Coil (not really visible in the photos). Can this be reused? Is there anything specific to the one that I could buy from the shop?

Thanks in advance




I had a Rolec charger and I have replaced (almost) all internals with an openevse kit

The conversion is fairly simple, and you can reuse several components: Contactor, fuses, etc.

I was about to publish a video on how to do it, but I haven't had the time yet

Here you can see my system installed

I can help you if you need more details


Thanks Javier, that's really helpful. A video would be amazing!


The first thing is to figure out what things you can salvage:

- Contactor- should be easy to setup with openevse board, and yes, the board can use 230v ac to turn it on

- I can't see any other items on the picture( like ground measurement, etc) so I can't say for sure, but in my case I was able to reuse the DC Residual Current Coil, so you may be also

What I would recommend is to buy:

- main board

-lcd screen board - IF you decide to use one

- both current transformers

For the wifi board you can buy a standard wroom-32 board from china and program it ( it will be much cheaper than the one from openevse, but may depend on what experience you have with ESP-32 programming). if price is not a problem, then by all means buy a wifi module from openevse ( if they are available)

If you decide to use an LCD Screen and button, you will need to buy also a push button

- If you are going to use ONLY wifi to control the board you don't need the LCD and button, besides you will not need to make a hole for the screean and make it weather proof

The price of the whole kit  is not super cheap as it comes from US, but it will cheaper than buying a new Charger

Make lots of pictures and document all the cables , if you can

Once you got all the materials,  plan where in the case you want to place the new board, and make sure it fits

If the current control board still work, try to leave the original cables, so you can revert if you have any problems with openevse

As I said, I did some video of my installation, but I'm not sure of the quality, so I will not publish it for now.

In any case, just contact me if you need any help


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