Saturday, April 22, 2017

The Road to Solar, Almost There!

Well, it's been a while since my last report, but since then I've been slowly building up our solar system in preparation for camping season.

Since I last posted, I purchased the last couple of big items.  SaskBattery in Regina had a sale on both solar panels and 6V golf cart batteries.  These batteries are designed with a large storage capacity and the ability to be discharged and recharged often.  I bought two 235 watt panels and 4 of the golf cart batteries, each 225 amp-hours capacity.

Here's how the batteries are arranged in the old truck tool box I'm using to contain the system.  The batteries are hooked up with what's called "series-parallel".  Each pair of batteries is hooked up in series (positive-negative).  That sums the volts of the pair, so 6V becomes 12V.  Then the pairs of connected in parallel so (pos-pos, neg-neg) so that we sum the amps to 450amp-hours.  I have a divider wall beside them as we don't want battery gases getting into the electronics in the charging compartment.

Next up is the board with all the charging parts...

In the centre of the board, surrounded by the various switches and fuses, is the charge controller.  It takes the power from the 36 volt panels and converts it to 12 volts for the batteries.  This conversion also increases the amps of charge.

I bought bulk cable and terminal ends from Great West Auto Electric in Swift Current and then did my own cutting and crimping.  The crimping tool I bought off Amazon.  It's a simple tool that uses a hammer to exert enough force to crimp the end on the wire.  It worked great for all the different sizes of wire I used, from 8AWG all the way up to the big 2/0 battery cable.  The result...

So once everything is wired up, I arranged it all nicely in the box.  Charging on the back wall, inverter in the bottom, and the batteries to the right of course.  Wire sizes as follows, 6 guage from panel junction box, to the charge controller, (through the red switch). 4 guage from the controller to the batteries, 2/0 through the batteries, and 2 guage to the inverter and the trailer 12V system.

So finally came the day to hook up the panels and try it out.   I laid out the panels and run the wires through the junction box, wiring the panels in parallel.  That maintains their 30 volts but doubles the current out to 15.6 amps fed to the charge controller.

So, did it work?  Let's check the battery monitor...

Above left we can see that we're getting 24.3 amps of charge, and we see on the right that it pushed the voltage up to 14 volts to speed the charging.  And it wasn't long before we saw this...

Yes, we're 100% charged!  We haven't tested too much yet, but Carla did test her 1200 watt hair dryer and it worked like a charm on power through the inverter.  It pulled 70 amps but we have plenty of stored energy and the inverter, which only showed about 900 watts while the dryer was running, is sized to run that kind of load, so no worries!

And now we wait for camping season!  Considering we have snow in the forecast this third week of April, I'd say it can't come soon enough!

1 comment:

Airmon said...

Congratulations on the new system!