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Daox 08-13-19 12:52 PM

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I got the handle printed. The handle is printed a fair amount more dense to take the load it will see.

I also got it installed. It was a bit tricky getting the screws all the way in there as the main housing is pretty long, but I managed. Thankfully the inside is big enough to get the screwdriver handle into.

pinballlooking 08-13-19 01:46 PM

It is looking good so far.

Daox 08-13-19 11:11 PM

Thanks! Its been a very fun project thus far.

Daox 08-14-19 09:13 AM

6 Attachment(s)
I ended up having to reprint the bottom piece. The two end holes were 1/16" off and it just didn't line up nicely. Cut twice measure once, right? :confused: I'm still working on that. Anyway, it now assembles nicely and things line up great. It even looks pretty good IMO. :)

I put some rubber D-shaped weather stripping in the bottom piece to cushion the battery pack. Its darn near perfect. It starts mashing the rubber with a ~1/8" gap.

With the handle attached, it was time to slide in the battery pack. It fits with a little resistance. There is a bit of a gap side to side, but not bad.

Next up I put the wires on the batteries. I ended up having to drill out the holes that go from the battery compartment to the electronics compartment. I apparently didn't look up what gauge wire to use to handle the possible 10A draw. I think I settled on 14 gauge.

Here we have the unit mostly assembled and ready for electronics.

Daox 08-15-19 08:20 AM

What would you guys recommend for fusing on this circuit?

Daox 08-16-19 01:01 PM

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I got the charge controller yesterday. This was a nice surprise as it wasn't due for another week or two.

I got a little bracket printed up for it.

And got it clipped in place.

I haven't hooked it up yet. I am still wondering what, if anything, I should put a fuse on.

Daox 08-19-19 12:00 PM

4 Attachment(s)
While waiting on the other electronic bits, I ordered and received mysolar panel. It measures about 18X14".

It is a 20W 12V panel sold by Newpowa. Operating voltage is 17.2V and 1.16A. This is what I will set the 'MPPT' controller to. It will maintain the 17.2V at whatever amperage the panel can supply.

I was concerned that achieving the 17.2V on a cloudy day was going to be an issue. The whole reason I went with the 12V panel was so I could get some charging done on cloudy days as I am only charging a 3.3V battery. But, my worries were quickly dismissed as I tested the open circuit voltage on the panel on an overcast day. I edited the brightness of this picture to accurately show what kind of light the panel was seeing. I hooked up the wire leads to the voltmeter and it was showing a nice 19.8V! So, even on cloudy days it should have no problem hitting the 17.2V. How much amperage we can get is obviously going to be low, but at least it will be something.

This is roughly how the panel will bit sitting for now. I may 3d print some sort of mount to hold it at a bit of an angle or something. We will see how it does.

Daox 08-22-19 06:04 PM

The DC-DC converters are getting close to being here. I hope they get here before the weekend so I can get this thing up and running.

I am still wondering if you guys have any thoughts on putting fuses into this setup?

NiHaoMike 08-22-19 08:35 PM

Just one fuse at the battery is all you need for your setup. If it's still 15W, a 7.5A or 10A fuse will give plenty of margin.

Daox 08-23-19 01:19 PM

Thanks Mike. The max draw will be a bit over 30w (15W per USB plug) plus the converter inefficiency.

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