Identifying a connector

[cojmh]

Hi all,

I am hoping someone can tell me what the "AC BACKUP" connector is called in the image below:



I am trying to get the plug that will fit into one of these ports on my inverter (which is a Solax not a Solis as pictured above) but it is proving very difficult.

Thanks in advance

[Oldgreybeard]

Looks like a Weiland connector to me:



Need to check the dimensions to be sure, but they are available from Farnell.

[cojmh]

Thank you OGB,

After you identified the manufacturer I have narrowed it down to a RST20i3 connector.

Tried talking to Solax but basically didn't want to know or help.

cheers,

Jon

[Oldgreybeard]

Looks like you need either this one: https://cpc.farnell.com/wieland-electri ... dp/CN19867

or this one: https://cpc.farnell.com/wieland-electri ... dp/CN19868

[cojmh]

Thank you,

I have ordered this one from Farnell (because my friend has an account there):

Farnell Wieland Connector

This was the last component I needed to get my power change over box sorted. When I get the bits (which will be about 2 weeks) I should be able to change one consumer unit manually over to use Grid/EPS/Generator.

Thank you for your help.

[openspaceman]

This was the last component I needed to get my power change over box sorted. When I get the bits (which will be about 2 weeks) I should be able to change one consumer unit manually over to use Grid/EPS/Generator.

Please do tell more as I intend to go down the route of a manual changeover switch to keep my panels and inverter live in the event of a power cut, maybe even eventually to go off the electricity grid completely.

[cojmh]

Please do tell more as I intend to go down the route of a manual changeover switch to keep my panels and inverter live in the event of a power cut, maybe even eventually to go off the electricity grid completely.

When I get all the parts and put it together I will put some more information up with pictures as I figure this will make it easier to understand what is happening. The lead time for some of the components is about 2 weeks so just bear with me. I hope to get it done by the end of the month.

[Oldgreybeard]

This was the last component I needed to get my power change over box sorted. When I get the bits (which will be about 2 weeks) I should be able to change one consumer unit manually over to use Grid/EPS/Generator.

Please do tell more as I intend to go down the route of a manual changeover switch to keep my panels and inverter live in the event of a power cut, maybe even eventually to go off the electricity grid completely.

Our system is setup to automatically change over to an emergency supply if there is a power cut. The battery inverter has an EPS output, but to make that useful I needed to make significant changes to the house wiring. I had a second consumer unit installed that just powers the essential circuits (lights, water pump, sewage treatment plant and a bank of sockets) and that consumer unit has a changeover relay that automatically switches to the EPS output from the inverter if the power goes down.

The other thing that had to be checked was the earthing for the house, as if there is a power cut and you are relying on an earth from the supply then there is a fair chance that the earth could fail at the same time. As it turned out this wasn't a problem for us, as we have our own earth rod, but it will be something that needs to be sorted for anyone that relies on the supply providing the earth.

[openspaceman]

Firstly cojmh I am looking forward to the pictures

Our system is setup to automatically change over to an emergency supply if there is a power cut. The battery inverter has an EPS output, but to make that useful I needed to make significant changes to the house wiring. I had a second consumer unit installed that just powers the essential circuits (lights, water pump, sewage treatment plant and a bank of sockets) and that consumer unit has a changeover relay that automatically switches to the EPS output from the inverter if the power goes down.

The other thing that had to be checked was the earthing for the house, as if there is a power cut and you are relying on an earth from the supply then there is a fair chance that the earth could fail at the same time. As it turned out this wasn't a problem for us, as we have our own earth rod, but it will be something that needs to be sorted for anyone that relies on the supply providing the earth.

OGB I looked at the automatic changeover and as the stuff I looked at suggested a 6 second delay I decided a manual one suited me. Also as our demand is low enough for my battery inverter to supply any load I have individually and the immersion does not get used unless the battery is full I do not expect to have to make any changes to the consumer unit.

I want a work around for an EPPI as it's not worth 400 quid for me to go down that route.

I know I will not be able to run the air fryer and hobs together in the absence of sunshine or a fully charged battery.

My little genset is 2kVA so as long as its sine wave is good enough to run the PV inverter I will have about 5kVA available and only washing machine and fridge with inductive loads (okay vacuum cleaner and dishwasher too but unlikely to use them in a power cut).

I am still waiting for the electrician to fit a changeover plus an outside cabinet for current and future battery and advise on the PV panel installation. He is a busy man and I can wait. Until I have the changeover switch I cannot test the cleanness of the generator sine wave.

The earth business I am aware of and almost certainly the changeover switch will have to be provided with a local earth.

Ultimately I would like to have the system running "islanded" without the generator running continuously but the cost of going the SMA route Nowty uses put me off a bit.

[cojmh]

Well this took a lot longer to sort out than initially expected - mainly due to the inverter connector. However I managed to get this installed around two weeks ago and tested for EPS.

So, the Saga with the connector.

Initially, I thought I had this sorted with the Weiland connector however when we came to test this with a small load (a work lamp) it turns out that the Weiland connector is not the correct one - The correct connector appears to be a copy of the weiland connector with one small, almost unnoticeable, different, the male part of the pin connectors are not perfectly round, they are infact tear shaped. So this meant I had to go back to Solax to get this sorted. I will put the saga here incase it helps anyone else get help from Solax.

Initially, I contacted Solax UK - who only really deal with installing businesses, so no response.

Then, I contacted their consumer help line - which is based in the Netherlands (I think) and they told me to contact their local installers. I contacted every listed installer within about 50 miles and was not able to speak to anyone but left messages explaining what I needed. I didn't hear back from a single one. I am going to guess that helping me with a connector was not worth their time compared with their other work at the time.

So I went back to consumer help line. This time they sent me a list of their suppliers in the UK. Again I spoke to every one of them. Most would not help because I am not a business and those that tried to help told me it was not something they had ever stocked and could not get hold of - basically they sold the full inverter but not individual parts.

So I went back to consumer help again - this time I was put in touch with what appeared to people at the main company in China. It took a couple of emails back on forth for them to realise that I was only after a plug and that there was not actually anything wrong with the inverter itself (so I did not need to remove the covers and photograph the internals of the inverter).

The very day after my emails to China, I received an email from Solax UK (who were the first people I contacted a month previously) who were suddenly going to help with my connector issue. I suspect someone in China might have prompted this response - but it could also be a coincidence and it took them a month to respond.

Solax UK then send me a connector - the correct connector - which was great but did not send me the outer case to the connector - meaning that live terminals would be exposed. Another quick email (and another week) and I finally got the right connector with the outer cover.

So I recommend that everyone keeps hold of every connector and questions their installer to leave everything with them because it can be a pain to sort this out afterwards.

Solax did send me the correct plug eventually - for free, but it was quite a lot of effort to get hold of something that should have been easy to sort out. Up until I actually got the connector I was not sure that I was going to be able to solve this issue so I was talking to an electronic engineer about the possibility of removing the connector in the inverter and putting in a different more available connection. Thankfully this was not needed in the end.

The actual install was quite straight forward and I will post up a few photos as soon as I can get them off my phone.

I am now able to run most of the house (excluding the kitchen, garage and one bedroom) off of the inverter in the event of a grid down scenario. I also took the opportunity to install an external generator plug so that I can run the house off a generator in the event of the batteries being empty (which is most of the time in the winter).

The change over in the inverter takes up to 5 seconds, which I had also read about in the user manual, You can hear some relays switching over when the grid goes off. Even when the grid goes down the PV stays up (no 5 second delay) so that is good. However I have decided to keep several UPS devices in place for continuity at the point of use.

The change over is done through two switches.

The primary switch has three options (grid - off - secondary power)
The secondary switch has three options (inverter - off - generator)

The idea behind the 3 position switch was just to further separate the sources of power - The switches were Schneider electronics industrial rotary switches - so nicely made and probably over specified for the job.

Anyway, photos will follow as soon as I sort them out from the Christmas ones.