Skipping the Inter-MAI event, wrong inverters and so on.

Firstly - I haven't been chasing images from the ISS for the Inter-MAI event that has been going on. 

Simply because it's from MAI. I don't feel a compulsion to support an event that is effectively Russian government funded given the state of the world. I have no problem working Russian individuals (unless of course there is evidence of those individuals sprucing pro-Russian propaganda), but I'm not inclined to support anything coming from that regime. 

I'd debated receiving them for the "challenge", but if I did that, I'd want to post them and what not, and that defeats the purpose. 

A silent protest perhaps? Of no real significance to the world in the grand scheme of things I suspect.

Closer to home...

I did some more solar testing of late.

I finally managed to get some improved production results. Still a long way from what I expect a 350w panel to achieve, but adequate I think. 

I managed to get from around 20w up to 150w briefly in between clouds. I determined the original panel wasn't behaving too dissimilar to another of the same model I purchased from elsewhere.  They don't perform great, but they're at least performing. Hopefully they'll improve when they're up closer to 2m from the ground.

I've created an adapter using 50A Anderson plugs that will wire the pair in series. It works. I've gone with series just because my MPPT controller has a 30A limit but can cope with a fairly high open voltage. 

I do like the effectiveness of the MPPT controller over what I've read the cheap PWM controllers are like. 

My "12v" panels are actually 18v, that are producing usually 22v in full sun each. 44v into the controller doesn't go to waste. It will happily convert that into around 14v and up the current into the battery and the load lines. 

The inverter...

Something I'd forgotten about a long time ago was the difference between modified sine wave and pure sine wave inverters. I purchased and installed a modified sine wave inverter - a 1000/2000w unit. It worked perfectly fine for charging drill batteries. It didn't work driving the drill press.

A couple of messages to the seller and they advised that the inverter is modified and that I'd need a pure. They offered to swap them, but I'd since lost the packaging and had cut the cabling. They still offered me a refund of half the price if I'd buy a pure from them. Sounds good. 

I opted for a 1500/3000w model. More power, but also getting well beyond what my wiring is capable of handling, resulting in a rethink. 

I've decided on running dual inverters. The modified was running direct to battery. I've since decided that I'll run it from the controller's load line (it'll handle 30A). I'm never going to find enough load that supports the modified to push it. 

Why would do this? 

Load control. The controller lets me set times that the loads can run, which will be all the time. It also means I can fully monitor said load remotely (and switch it). Everything that I plan on running on the modified is effectively just battery chargers, so they'll be always on. It'll also handle my soldering iron. The load line is fed from solar when it's producing and battery when it's not. The controller will cut the load if the battery drops too far. If it doesn't, the battery protector will. 

The pure sine wave inverter will be fired up when required. Given it'll need cabling spec'd for potentially 250A, it's too big to retro-fit into my switch box. I'll use a 250A car breaker between the inverter and the battery for protection and I'll have a second mini breaker box for the AC side with an RCD on it. 

I'll have a couple of power points floating around the shed connected to this for when I need to use loads that don't work with the modified sine wave (like the drill press.. ). 

Overall, it's cost around a grand in gear to get solar ready excluding the battery that I haven't yet purchased. I've been testing on an old 105AH battery that I think has seen better days. I expect to be replacing that soon. 

For my usage, I suspect I'll wind up with a pair of batteries. I suspect my constant current draw will be around 2A, of which based on yesterdays reports, the array will handle during daytime without too much bother and still be able to charge. 

During winter that might be a bit more of an ask - and having that second battery will give me a little more overhead and will ensure that there is still power when I need it. 

Hopefully not being in there that often will help give the batteries a chance to charge.

I'll definitely need to do some monitoring as we head into winter to see what production vs load is looking like, and what the state of charge is for the battery bank. If necessary, I can always go and turn off the parasitic load - if that becomes a common enough requirement, I'll move the light circuit direct to battery so I can program the controller to only run the load during daylight hours. That'll be adequate to keep things like the tool batteries charged.

Certainly not perfect and I'm learning this one as I go.