Build a decent solar setup

[Iain_S]

1 hour ago, Ian Mac said:

That is interesting as our surveyor - god rest his sole, made us fit a total isolation switch, as well as a swich which turns of everything but those you mention, which we use when we leave the boat.

That is arguably "best practice", although I'd fit the additional switch to just the "always on" services.

[Alan de Enfield]

4 minutes ago, Iain_S said:

That is arguably "best practice", although I'd fit the additional switch to just the "always on" services.

It may be, but for a BSS examiner to 'make us fit one ' in contravention of the BSS requirements is just plain WRONG.

These people should be bought to book, but it never seems to happen.

 

As I have mentioned a number of times I had pretty much the same experience over the requirement to fit an RCD. I reported him and was just told 'an internal review will take place'.

Edited June 25, 2020 by Alan de Enfield

[RufusR]

I have a Combiner box for my 6 panels , each panel has a fuse then goes through feedback diodes then lightening surge suppressors then a large breaker . Came all assembled in a IP rated metal box with MC 4 connectors on the inputs all for £125.00 . couldnt have made it for that . Combines all six panels in Parallel which I wanted ( will handle up to 150 v so can have series strings and parallel those if required ) and gives all extra safety , In addition solar controller has ARC fault protection ( Only one that does ) and Ground fault protection included . I think powerful arrays need protecting no matter what the rules say as you have a lot of voltage and current running around your roof that you cant switch off easily if something goes wrong . Interesting seems the US have tougher rules on this than over here ( all the stuff above comes from US ) which is rare when it comes to safety things . 

 

 

[Iain_S]

20 hours ago, Alan de Enfield said:

It may be, but for a BSS examiner to 'make us fit one ' in contravention of the BSS requirements is just plain WRONG.

These people should be bought to book, but it never seems to happen.

 

I agree, but it wasn't clear from the post I was replying to whether it was a BSS inspection or not. If it was, then the rules are clear and the inspectpor was wrong to insist on it being fitted.

[Alan de Enfield]

5 minutes ago, Iain_S said:

I agree, but it wasn't clear from the post I was replying to whether it was a BSS inspection or not. If it was, then the rules are clear and the inspectpor was wrong to insist on it being fitted.

That's a fair point, but I cannot imagine any other scenario where a surveyor could 'make' you fit one, advise or suggest -yes, but not force you to do it,

[robtheplod]

So with lockdown/boredom and cabin fever setting in I'm just checking figures for my (eventual) solar fitout.

 

I'm happy with the kit i have in mind but have a query as the Victron spreadsheet i have highlighted a query.....

 

 

so its letting me know I'm getting close to 50A, but is this a hard limit?

 

As detailed before I'm thinking about 4 x 175w Victron panels in two groups of two, so serial/parallel layout. Specs for the panels are:

 

23.7 open circuit voltage (Voc)

9.03 amps max power (Impp)

 

so doing the maths one serial pair gives 47.4 volts and 9.03 amps, other the same, then combined give total of 47.4 volts and 18.06 amps. If I've got this wrong let me know!!

 

The controller I have in mind is the Victron 100/50 MPPT controller (50A Victron MPPT SmartSolar 100-50 - 100VOC PV Charge Controller (bimblesolar.com))

 

This controller states max 700w input, although 47.4 x 18.06 gives 856w so more than capacity - I know its all theoretical but is this of concern?  I'm flummoxed why i get this when the panels are 175w each (4 x 175 is 700w) .....    Does the controller take 700w then disregard the rest?  Keen to not stress it.. i think i read a while ago the only thing you need to keep under is the voltage on these controllers to avoid damage, is this correct?

 

will 4mm solar cable be ok for this, or is 6mm best?  length could be length almost of 58ft boat for one pair...

 

any guidance/re-assurance gratefully received!!

 

rob

 

 

Edited February 16, 2021 by robtheplod

[David Mack]

If the panel is producing its maximum power the you won't get the open circuit voltage - you only get that when the current is zero. So the maximum power is not going to reach 856w.

[robtheplod]

2 minutes ago, David Mack said:

If the panel is producing its maximum power the you won't get the open circuit voltage - you only get that when the current is zero. So the maximum power is not going to reach 856w.

ah ok, so should i be using the 'Max power voltage' which is stated at 19.4v instead?  that bring si very close to 700w so makes sense..... thanks!!!!

[David Mack]

Yes. But the controller needs to be rated for the open circuit voltage as it could still see this on a sunny day when the batteries are fully charged, and the current is minimal.

[robtheplod]

1 minute ago, David Mack said:

Yes. But the controller needs to be rated for the open circuit voltage as it could still see this on a sunny day when the batteries are fully charged, and the current is minimal.

ah, ok so the controller isnt suitable?

[David Mack]

The max VOC of the controller is 100V, so should be capable of running your 4 panels in series if you wish.

[robtheplod]

thanks David

 

yes thats certainly an option... as the two sets sit at different angles i though splitting them made more sense rather all series, but if that makes this viable then will certainly look into that.. many thanks for your help.

[robtheplod]

Now I've painted the roof I'm looking again at this....

 

Things have moved on a little and CraigSolar are about to get 200w panels in, which are the small physical size I'm after (200w Solar Panel (148x68cm) — Craig Solar) - can be mounted either along the centre of the roof (in between mushrooms) or two can fit together across the roof if all space is used up.

 

My original plan was 4 panels, but i actually have space for 6 ..... ignoring actual requirements, how many people fit 'enough' solar only to wish they had gone further?  I'm wondering which way to go, especially as they will be laid flat, so wont have the benefit of being angled so may need to 'over' quote on this? As the panels will be low profiled on the roof I hope to avoid the 'solar farm' effect!

 

Can you have too much i guess is what I'm asking!

Edited June 4, 2021 by robtheplod

[Alan de Enfield]

15 minutes ago, robtheplod said:

Can you have too much i guess is what I'm asking!

 

Not really.

 

You may 'have way too much' In June, July and August, a little bit 'over the top', in May and September, just enough in March and October but still not have enough in November, December, January and February.

 

The only thing 'having too much' does is :

 

1) Empty your wallet more than 'not having enough' will.

2) Extend the season when you don't need to run the engine.

 

Its a bit like Goldilocks :

 

1/3rd of the year It'll be 'too hot' (too much)

1/3rd of the year It'll be 'too cold' (not enough)

1/3rd of the year It'll be 'just right' (just right)

Edited June 4, 2021 by Alan de Enfield

[Bubblebuster]

So what's the latest guys on solar panels.

Trying to find a price/company to fit flexible/adhesive panels on a 57' new build (5/6 panels?)  

Willing to pay a fair price for a decent set-up, but not willing or wanting to be robbed!

 

These two guys seem to have it well sorted, but on asking they tell me it was a couple of years back and cannot remember?

https://www.youtube.com/watch?v=7N8MDSI1R5Y

[LadyG]

37 minutes ago, Bubblebuster said:

So what's the latest guys on solar panels.

Trying to find a price/company to fit flexible/adhesive panels on a 57' new build (5/6 panels?)  

Willing to pay a fair price for a decent set-up, but not willing or wanting to be robbed!

 

These two guys seem to have it well sorted, but on asking they tell me it was a couple of years back and cannot remember?

https://www.youtube.com/watch?v=7N8MDSI1R5Y

Generally flexible panels are more expensive, if stuck to roof they will overheat. Check out guarantee.

I have rigid panels, they are great from mid March to mid October.

You could ask locally for advice on fitters.

I have two panels on a frame which allows me to use the centreline without much problem, also looks OK.

Edited April 27, 2022 by LadyG

[Rob-M]

We had two panels and controller installed last year by Ed Shiers at Four Counties Marine Services.

[robtheplod]

Hi All

 

You'll be amazed to hear I've got the kit and about to fit!

 

I have a query though in that the MPPT obviously connects to the leisure batteries, so if i turn off the mains charger (marina based) then my starter/BT battery wont be getting any charge. I know this is a small issue as they'll be fine once moving again but thought I'd look to see if the solar could charge these as well. Below is a very basic diagram of my charging arrangement.. i'm struggling to see how i can do this and not mess anything up....  one idea was to just put a single jumper lead from the green spot to the leisure when in the marina???   any better ideas?   thanks!!   Rob

 

Edited January 19, 2023 by robtheplod

[Alan de Enfield]

 

I just simply put a Positive (+) Jump lead on both the domestic battery and the starter battery (+) terminals (but they are fairly close together) - where is your BT battery ?

[robtheplod]

Just now, Alan de Enfield said:

 

I just simply put a Positive (+) Jump lead on both the domestic battery and the starter battery (+) terminals (but they are fairly close together) - where is your BT battery ?

its the other end of the boat in the chamber itself..... 

 

i like simple methods, sounds good Alan!!!

[Alan de Enfield]

1 minute ago, robtheplod said:

its the other end of the boat in the chamber itself..... 

 

i like simple methods, sounds good Alan!!!

 

 

If the 'output' side of the battery isolator serves both starter and BT battery then putting a jump lead on the starter battery + terminal should feed, as well, to the BT battery.

 

If that is the case - and they are connected - does using your BT also deplete your starter battery ?

[robtheplod]

The battery isolator has three pins, one input (where the mains charger and starter alternator connect) and two outputs, one to the starter battery and one to the BT battery, so the batteries are isolated from each other. I'm fairly sure one cant drain the other...

 

The isolator is this one: Sure Power 702 Multi Battery Isolator 70A 1 Input 2 Battery : Amazon.co.uk: Automotive

[robtheplod]

All now fitted. Pleased with the results. Thanks to all who have advised etc!

[Guest]

1 hour ago, robtheplod said:

All now fitted. Pleased with the results. Thanks to all who have advised etc!

 

You do know you need to clear that snow off them?  😉

[David Mack]

Two VSRs connecting the three batteries will ensure that all batteries get charged when there is a charge source available (alternator, mains charger or solar). Automatic fit-and-forget.

Edited January 22, 2023 by David Mack