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Will Prowse finds easiest off-grid PV system

Posted: Sun Oct 24, 2021 7:17 pm
by Stan

Re: Will Prowse finds easiest off-grid PV system

Posted: Sun Oct 24, 2021 8:07 pm
by Joeboy
Great to see an accessible functioning system c/w battery at an achievable cost ($2,800 US). Imagine the volumes of folk that could get in and begin. That's smashing!

Re: Will Prowse finds easiest off-grid PV system

Posted: Sun Oct 24, 2021 11:16 pm
by Tinbum
Why does he have black heat shrink on the + battery connection and vice versa. :o

Re: Will Prowse finds easiest off-grid PV system

Posted: Mon Oct 25, 2021 8:01 am
by Stan
Well spotted. That’s confusing and bad. He says that you can buy the leads at any automotive store!
Also, for us in the UK, the cable colours on the load side are not what we expect.

Re: Will Prowse finds easiest off-grid PV system

Posted: Mon Oct 25, 2021 8:29 am
by Stinsy
Yep if I saw a black cable sleeved red I’d assume positive, and red sleeved black would be negative. The principal that sleeving overrides the underlying cable colour is ingrained.

The American electrical system is bonkers. Basically consumers didn’t want to change their lightbulbs when 100V DC power was replaced with AC (see “current wars”), so they ended up with a crazy split-phase 120/240V system where red and black are the phase conductors running 240VAC and the white is linked to the centre tap of the transformer and earth. If you want 110V you link to either red or black and white, if you want 240V you link to red and black and ignore the white.

Re: Will Prowse finds easiest off-grid PV system

Posted: Mon Oct 25, 2021 12:11 pm
by nowty
Stinsy wrote: Mon Oct 25, 2021 8:29 am The American electrical system is bonkers. Basically consumers didn’t want to change their lightbulbs when 100V DC power was replaced with AC (see “current wars”), so they ended up with a crazy split-phase 120/240V system where red and black are the phase conductors running 240VAC and the white is linked to the centre tap of the transformer and earth. If you want 110V you link to either red or black and white, if you want 240V you link to red and black and ignore the white.
Thats not quite as nutty as it sounds as usually you get electrocuted with respect to earth so you only get half the voltage and less chance of death. I have used a 110v system on a construction site (many moons ago before RCDs) with an earthed centre tapped transformer, so only 55v to earth, almost no chance of death.