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Oops …
3 years ago
General
Oops …
If you’re not screwing somethin' up every now and then you ain’t doin’ nothin’ …
When I was setting up a bit of solar I didn’t do as much research as I should have and it came back around to bit me in the ass. My initial plan was just enough power to cover the basics if the grid went down for a bit. Sixteen panels and a dozen batteries (set up in sets of four for the forty-eight volt inverter) seemed to cover things if we didn’t have cloudy/rainy days. As the days got warmer so did usage and it became obvious what little I had just wasn’t enough.
This is where the lack of research jumped up and bit me on the butt. The batteries I’m using recommend not having more than four sets connected together or you get the different built-in battery management systems fighting over voltages/power. What they do they do well, they just don’t scale. Which means when I upgraded to two dozen panels and two dozen batteries I couldn’t have all the battery sets connected at once.
Now these are 12.8 volt 100Ah batteries, so each ‘set’ of four is right about 5kWhs of power, and going from 15 to 20kWhs now keeps things from dying just before the sun came back around. The other eight batteries? A 10kWh reserve in case we ever need it. On good charging days I’ll flip from the primaries to the reserves to top them off.
All that and some of you are still wondering ‘so what was the oops already?’
I had flipped over to add a bit of charge to the reserve – and come dark I forgot to flip back to the primaries! So a little after six this morning I get a call (home phone doubles as an intercom) ‘the power’s out!’ So it is, flip things back to run off the mains and enjoy having lights while I wait for the dawn – and discover my goof.
To be honest I’m surprised/pleased that just two sets powered the place as long as they did.
Live, learn and try not to take too many shocks to the system.
If you’re not screwing somethin' up every now and then you ain’t doin’ nothin’ …
When I was setting up a bit of solar I didn’t do as much research as I should have and it came back around to bit me in the ass. My initial plan was just enough power to cover the basics if the grid went down for a bit. Sixteen panels and a dozen batteries (set up in sets of four for the forty-eight volt inverter) seemed to cover things if we didn’t have cloudy/rainy days. As the days got warmer so did usage and it became obvious what little I had just wasn’t enough.
This is where the lack of research jumped up and bit me on the butt. The batteries I’m using recommend not having more than four sets connected together or you get the different built-in battery management systems fighting over voltages/power. What they do they do well, they just don’t scale. Which means when I upgraded to two dozen panels and two dozen batteries I couldn’t have all the battery sets connected at once.
Now these are 12.8 volt 100Ah batteries, so each ‘set’ of four is right about 5kWhs of power, and going from 15 to 20kWhs now keeps things from dying just before the sun came back around. The other eight batteries? A 10kWh reserve in case we ever need it. On good charging days I’ll flip from the primaries to the reserves to top them off.
All that and some of you are still wondering ‘so what was the oops already?’
I had flipped over to add a bit of charge to the reserve – and come dark I forgot to flip back to the primaries! So a little after six this morning I get a call (home phone doubles as an intercom) ‘the power’s out!’ So it is, flip things back to run off the mains and enjoy having lights while I wait for the dawn – and discover my goof.
To be honest I’m surprised/pleased that just two sets powered the place as long as they did.
Live, learn and try not to take too many shocks to the system.
Vix
Vix
Gee, maybe I should write a manual for the silly thing in case one of my brothers (or someone else) needs to turn it on - or get the house back on the mains!
I took one look at the rat's nest (rats are much neater!) and told him I'd help - but only if we did everything my way. He didn't like it, but finally agreed - then started screaming bloody murder when I started unpluging everything from EVERYTHING!
His wife laughed at the wadded tangle I pulled out from behind the system, but stopped laughing when I thanked her for volunteering to help us unravel said tangle.
Took us a couple of hours, but when we were done even his wife knew what to hit where to make things happen.
Oh I used to do AV set ups on the side for my customers. Half the time was spent programming remotes.... no one wants to read directions and would complain about faulty equipment. I'd check to see if batteries were installed. Second test you needed a camcorder - those can see the IR beam from the remote - made sure the damn remote sent out signal...
Sounds like a bowl of spaghetti wiring set up. Dealt with a few of those over the years.
I could rig an alarm to alert me when the battery voltages are reaching their cutoff limits, but nothing can keep me from not noticing the errors in my ways!
If I hadn't still been half asleep I could have just flipped the system over to the still full sets of batteries and gone back to bed. Something to add to the checklist. (I didn't think to just flip to the reserve because I was worried about might be wrong to have drained what I was thinking was the primaries so quickly (extra drain or an actual problem with my system.))