Solar power for your shed/garage/cabin (smaller than a house, basically)

If so, I'm intending on interrupting that circuit from the smart battery protect to the input terminal on the inverter with a Shelly1 WiFi switch, which will give me the ability to turn the inverter on and off via the Shelly app on my phone.

Yes, that should be fine.

The Victron diagram shows a small inline fuse to prevent a short circuit on that skinny wire making it catch fire. You could move your wire to the far side of your mini fuse block to achieve the same thing.

I think my system needs more panel

It's only going to get worse as winter goes on. Keeping that wifi router going 24/7 on a week of January gloom seems ambitious.

Yeah, I agree - this is since I got the logging/reporting box:

And a close up of finally getting to float today, when the sun was strong and the inverter was turned off (and the AP wasn't plugged in):

A second 120w panel arrives tomorrow.

The Victron diagram shows a small inline fuse to prevent a short circuit on that skinny wire making it catch fire. You could move your wire to the far side of your mini fuse block to achieve the same thing.

I shall do this.

You can flash open source firmware on the Shelly1 to make it compatible with Apple HomeKit, avoids the Shelly app. Mongoose-os-apps on GitHub, project Shelly-HomeKit.

Ok, potentially as per @grams advice, I have re-worked things:

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Behold!

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I had a strip of LED lights (around 2m) plugged into the 12v DC board, plus the inverter running but with no load tonight. What I think to have been the on-board BMS of the Renogy battery cut all power twice, then turned back on again.

I was quite a surprise - the LED tape is meant to be around 5w/m so 10w continuous from that plus 5w from the inverter gives a total of 15w, so not as if I'm running a toaster whilst boiling the kettle.

Or am I missing something?

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Voltage for the battery reads 13.28, so far from empty (that's ~80% of total capacity).

Hmm

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Either you’ve got an intermittent short somewhere or a dodgy battery. Neither seems particularly likely though - the short would have to be somewhere where it didn’t blow a fuse.

Is there any extra datalogging on the system? Does it inform you of any alarms that have been triggered (overload etc)?

maybe disconnect the LED strip and see what it looks like

All the loads are fused, I’m thinking the onboard BMS is the culprit.

I did check the battery protect and it’s set to disconnect loads when the voltage drops below 12v, which hasn’t happened according to the log, but I can set it to 10v and then see if I still get the switch off, in which case it’s likely to be the BMS I think?

Your voltage measuring thingy is before the disconnect though? So those dips on your graph are showing the battery either switching itself off or having its voltage pulled low by a heavy load.

The 60A fuse is big enough that the right size load (maybe 80-100A) might trip the BMS before the fuse blows. That would require some very weird fault in your inverter though…

The inverter was on, both times, but running without a load. The only load was 2m of LED's, so ~10w from that, 5w from the inverter.

The voltage measuring thing is attached to the battery terminals.

The bid dip in voltage happens just after the chargers shut off from float.

In different but related news I have bought a much better battery monitor (which has current in addition to voltage).

It has to go on the negative side - between the battery terminal and all loads.

I was going to take advantage of the reorganisation that this will require to add another bus-bar to my setup, so it would go roughly as follows - is this lunacy?

Solar charge controllers 1 and 2>bus-bar>battery>fuse>battery protect>bus-bar>all loads apart from inverter (which comes off the "in" terminal of the battery protect)>negative bus-bar>new battery monitor>battery

This is mainly because I have loads of lugs on the positive battery terminal now and it's messy, I'd rather have a single cable going from the "in" bus-bar to the battery.

Actually this probably needs a diagram as text isn't describing it accurately.

Here we go

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I think I've worked out what the issue was with the power cutting out - the reporting box/IOT Globallink 520 has a relay that you can control through the remote management console.

I had this setup to turn power off to the load side of the board, just as belt and braces really.

Periodically the Globallink 520 just starts power-cycling, and each time it power cycles it opens the relay which de-powers the load side of the board, then closes it and the power comes back up.

= I think it's fucked, potentially, which is annoying.

Anyway, I've removed that aspect of the board so there is no remote cut off for the load side, but it does just work without cutting out randomly now. Which is nice.

Looks good Neil, all though I have 230v mains run out to it I also have a simple 12 v system on my shed with a solar panel via a controller to a battery and small fuse board powering some 12v led lights that operate when I open the shed door and also use to keep a few 12v batteries topped up.

This site has some useful info and diagrams.
https://faroutride.com/electrical-system/

So I just bought a pottingshed and fancy a light for it. It’s only 8x6’ so something basic from Amazon is probably fine but there’s a myriad of options with more features than I could ever fathom.
Any tried and tested options on a budget? Want on/off, either switch or proximity and would be really nice if it could go on a timer so I can give any seedlings a little extra light for a couple of hours morning and evening.

I looked at shed stuff a coupe of years ago and the camping / caravan sites had some useful info. Decided to put it off until the shed falls down and need a new shed lol

Fair enough. There’s a ton of sub £50 options on Amazon so sure any will do the job but would nice if it would last a few years hopefully.
In no rush

I have these which seem to stay on for ~20 mins whenever something goes past and don’t seem to run out of battery.

And something from wickes that was £10 and has a separate solar panel and a pull cord, but no movement sensor.

Timers are probably extra but those little ones may be enough depending what you’re doing in the dark in there :)

Reayos Solar Lights Outdoor, Upgraded Optics Lens Security Lights, 【283LED/3 Modes】 PIR Motion Sensor , IP65 Waterproof Outside Powered Solar Wall Lights for Door Fence Garden[2 Pack] https://amzn.eu/d/72kTyK6

Cool, thanks for the info but can’t see a pic or link to the ones you’ve got?
Mostly looking to light the inside of the shed while I’m in there sowing seeds and hanging out in autumn/winter up the allotment. If it’s bright enough to provide supplemental lighting for seeds then great but not expecting anything that good really.
I won’t be able to keep anything valuable in there so it being a security light is secondary anyway.

Weird, sorry - it’s showing me a link in there (the “these” I made bold is a link) but I must have messed something up.

Link now added to the bottom