(Yet another) Lithium Upgrade!!

[lonnie]

Good evening all,

Thanks to the wonderful information I've gathered from other threads (particulary [Broken Link Removed]) and help from DJL220 and Two on Tour I think I've finally got a plan for my upgrade.

The kit is ordered (thanks mainly to RogerIvy) and with the help of the diagrams in the post above, I've tried to map out the installation. I dont have a great amount of space in the 'garage' under bed and the diagram below is to scale.

I'm limited with Visio skills and the cabling in real life will be more ordered - but I guess it shows the general positioning.

Does it look ok to you experienced funsters? Or is it a dog's dinner?

My main concern is whether I'm trying to get two much kit in a confined area. My plan is to sort of 'box' the install in with ply but with large mesh 'windows'. Something like this on the front and end panels...

I'd welcome any feedback.

TIA, Martin

 

[lonnie]

They have got that wrong as an RCD won't work on an inverter output unless the neutral & earth are bonded.

Have a look at Victron inverters much better quality.

Thanks Lenny,

I'd love to complete my Victron kit with one of their inverters but having looked at the price, and already having the Giandel, there is no way I can get that authorised this financial year!

I've emailed them again as I'm sure there must be a way of getting leakage protection from their inverter.

Cheers

 

[lonnie]

They have got that wrong as an RCD won't work on an inverter output unless the neutral & earth are bonded.

Have a look at Victron inverters much better quality.

Please accept my apologies Lenny, I didn't realise you were away until I saw your 'heading south' thread - I wouldn't have mithered you if I'd known!

We'll be following a similar route on 13th October - assuming I get the electrics finished

 

[ianp]

For clarity OP....on your post 1 you show a link between the earth point in the PDU and the inverter case. Is this link real, does it exist and does it go to an earth stud on the inverter case which is provided to facilitate an earth point for the inverter output by the manufacturer? Also is the 'auto relay' real or an ideal aspiration and what is the function of its 'auto' ability? The graphic incidentally appears to show nonsense but I take it that this is just a limitation of available graphics...! Why have you not gone for a simple 3 pole break before make rotary switch? It seems to me that if your earth link to the invertor (above) is real then if you place the RCD in your diagram between the 'auto relay' and the MCB within the PDU then the RCD will cover both EHU and Inverter. This assumes that the interconnecting wiring is the absolute minimum as they are unprotected ! ( 'Disclaimer'.....This of course isn't advice but just an observation and may well be incorrect! This being the case you should if in doubt seek professional advice.)

 

[lonnie]

For clarity OP....on your post 1 you show a link between the earth point in the PDU and the inverter case. Is this link real, does it exist and does it go to an earth stud on the inverter case which is provided to facilitate an earth point for the inverter output by the manufacturer? Also is the 'auto relay' real or an ideal aspiration and what is the function of its 'auto' ability? The graphic incidentally appears to show nonsense but I take it that this is just a limitation of available graphics...! Why have you not gone for a simple 3 pole break before make rotary switch? It seems to me that if your earth link to the invertor (above) is real then if you place the RCD in your diagram between the 'auto relay' and the MCB within the PDU then the RCD will cover both EHU and Inverter. This assumes that the interconnecting wiring is the absolute minimum as they are unprotected ! ( 'Disclaimer'.....This of course isn't advice but just an observation and may well be incorrect! This being the case you should if in doubt seek professional advice.)

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[lonnie]

Hi Ian,

Sorry the diagram isnt clear. So from the inverter 240v outout (13a plug) there is a 3-core flex that connects live and neutral into the relay and the earth connects to the earth 'bus bar' in the PDU. There is an additional ground from the inverter case to the vehicle chassis.

The relay is in situ and has worked perfectly since I installed it about a year ago. It's this one from Dold...

I've tried to show it on an earlier picture but it basically takes a feed from the EHU (via the main PDU RCD) (NC from memory) and then switches if there is no power from EHU and I turn on the inverter.

Because the output from the relay feeds the sockets circuit through a C16 MCB (next to the relay) I was questioning whether it would be possible to swap the sockets MCB with an RCBO.

I have to admit, the question stumping me was 'how to ground the neutral'!

Fully accept the disclaimer btw

 

[ianp]

Hi Ian,

Sorry the diagram isnt clear. So from the inverter 240v outout (13a plug) there is a 3-core flex that connects live and neutral into the relay and the earth connects to the earth 'bus bar' in the PDU. There is an additional ground from the inverter case to the vehicle chassis.

The relay is in situ and has worked perfectly since I installed it about a year ago. It's this one from Dold...

View attachment 955129

I've tried to show it on an earlier picture but it basically takes a feed from the EHU (via the main PDU RCD) (NC from memory) and then switches if there is no power from EHU and I turn on the inverter.

Because the output from the relay feeds the sockets circuit through a C16 MCB (next to the relay) I was questioning whether it would be possible to swap the sockets MCB with an RCBO.

I have to admit, the question stumping me was 'how to ground the neutral'!

Fully accept the disclaimer btw

Ah OK on the switching relay....... so on the graphic you have the supply contacts a bit mixed in that each 'contact' should be either both L or N and not both L and N if you get what I mean. On the 'earthing ' side then it looks like the case 'ground' stud is connected to battery negative (via the chassis).
Going forward you need to establish if a bond exits within the case between the 'neutral' and 'earth' points of the AC output as without it the RCD will not function as I think you know. If one doesn't exist within the case then you'll need to establish if the unit is so designed as to accommodate an external bond, neither of which aren't always the case. Definitively only the manufacturer can tell you this. I think you need to go back to them and get some clarity as to what was meant by their first reply! Or as mentioned above buy a 'quality' unit where the status is all laid out in the manual rather than some vague mumbling as is in yours I believe.
Also bear in mind that there is a school of thought that asks that because the output of the inverter is not conscious of the outside world and is said to be 'floating' then therefore what is the function and need for an 'earth' as its presence simply increases the potential of a 'shock' event. Without one the only way to be 'shocked' is to touch both sides of the supply (L&N) and in that instance you become a 'load' on the system and as such even if fitted with an earth and an RCD you wouldn't trip it ........ so 'they' say....!
And again, all just an observation and very likely incorrect so treat with all due caution !

 

[Simonjdcooper]

Is there a way of telling whether your solar panels are wired in parallel or in series from just looking or would it be better to check the output from them?

 

[bigtwin]

Is there a way of telling whether your solar panels are wired in parallel or in series from just looking or would it be better to check the output from them?

If you can see the connectors they’re in series if you see a small loop between the panels with a separate long cable from each of the two panels.

In parallel both cables from each panel are likely to be the same length and connecting into a ‘Y’ connector.

That may not be the best description but it’s the best I can do for now.

Ian

 

[lonnie]

If one doesn't exist within the case then you'll need to establish if the unit is so designed as to accommodate an external bond, neither of which aren't always the case. Definitively only the manufacturer can tell you this. I think you need to go back to them and get some clarity as to what was meant by their first reply!

Cheers Ian - Giandel support response to my follow up was "consult a professional electrician"!

I'll do more research but your description of the inverter behaviour makes sense. I'll probably buy the RCBO and test it.

And then start saving for a Victron

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[The joker]

Cheers Ian - Giandel support response to my follow up was "consult a professional electrician"!

I'll do more research but your description of the inverter behaviour makes sense. I'll probably buy the RCBO and test it.

And then start saving for a Victron

Just bought a victron MultiPlus Inverter/Charger 12V 2000VA for £740 which I thought was a bargain? So thats the target

 

[lonnie]

Just bought a victron MultiPlus Inverter/Charger 12V 2000VA for £740 which I thought was a bargain? So thats the target

Someone's doing alright for themselves!

 

[cyberyacht]

The voltage is probably the most reliable way of checking. If it's sunny and you have say three panels in series, the voltage at the MPPT input will be around 30-50V. A single panel or one in series will be around 10-17v

 

[DandG5515]

Thanks again both. The Explorist blog post was REALLY helpful thanks.

It helps me to see actual numbers so using the basic maths in the post, it looks like I'd see a vast improvement just switching to parallel (as the max voltages are virtually the same on the Victron panels)

View attachment 952717

It also reminds me that I added the 90w panel and saw a nominal increase of 4w

View attachment 952718

Hopefully my foolishness will help guide other funsters in the future!!

Just to carry on from this point it’s only half the story, if you have a 10m run (ie 20m total cable) from panel connectors to controller in 6mm series will give 1% losses, parallel could give you 15% losses. Someone with better knowledge than me should check the cable size.