Charging Tower Mk II

[mkovalcson]

I think this tablet is going to work well.
That is the last piece I needed except for the BUMP controller and RFID stickers.

Hopefully they are still on track for next week....

[mkovalcson]

Despite the very cool looking new products announced at http://www.bumpcharger.com/ I still intend to finish what I started

I wish them the very best of luck with it and I hope they do well.

If this had already existed before I got started, I would have seriously considered getting one.

Below I have the 48V DC for the BUMP and AC for the tablet charger routed to the bin. There is just enough room to pass the EC3 connectors through to allow dissassembly since one side of the wires are screwed down to the power supply.

[mkovalcson]

Originally Posted by Tim Marks

Hi:

We lined the insides with drywall material which is flame-retardant and of course non-conductive. Since the top of the toolbox supports a tray, we cut another piece of drywall to lie across that as a shelf.

I've been looking at cement board which won't ignite and is readily available. It's 2.55lbs per square foot and I think I could build something that weighs under 10lbs that safely holds up to 4 x 12S sticks.

I'm defining safely holds as shielding me from the sparks and fire while I transport the batteries outside.

This looks like a great material for battery storage. I would build a frame to go around it that has handles on the side.

The critical thing I read about cement board is to wear a respirator, goggles and gloves and make sure to wash any dust off when you are done working with it. The dust is very dangerous when inhaled.

I think I'll mount a smoke detector under my corner desk where I do most of my charging and get a new fire extinguisher as well.

I think I would use something like this to cut the cement board, and I think I would cut it outside, with respirator and eye protection that sealed around my face.

I would also attach my dust collection vacuum directly and use the HEPA bag bypassing the cyclone.

http://www.amazon.com/Diablo-10-Inch...dp/B001CJNYW4/

[nightflyr]

HardieBacker 3 ft. x 5 ft. x 1/4 in. Cement Backerboard

1.9 lbs / sq.ft

[mkovalcson]

Originally Posted by nightflyr

HardieBacker 3 ft. x 5 ft. x 1/4 in. Cement Backerboard

1.9 lbs / sq.ft

This is what I'm thinking about.

I'm looking at using a combination of 1/4" and 1/2" cement board and thinset to create the non-burning section. I'll use thinset to seal the cement board. I have some 3x3x12" cardboard mailer boxes coming. They will protect the batteries from abrasion and act as forms to hold the cement board in place while the thinset dries. I'm not concerned about a bit of cardboard burning in a fire as long as the fire is contained.

there will be 6-7" vertical spacers that can drop in to support the non-12S stick batteries.

There will be a 1/2 plywood frame holding the cement board with handles in the back. It will be 6" from the top of the cement board. I'm thinking Lock Miter bit construction with glue and no fasteners.

There will also be a cover with a vent hole for escaping smoke and gases that directs the smoke away while carrying this out of the house.

I'm planning to build one set for each side of the charging tower and I'm expecting these to stay at home.



After I learn to work with Cement Board a bit more, I'm thinking of building a LiPO storage area with them.

[nightflyr]

I understand your train of thought... But
Why not make your life easy...
Build a mold ( you have the wood tooling) and pour a plaster cast.
One piece simple and lighter

[mkovalcson]

Originally Posted by nightflyr

I understand your train of thought... But
Why not make your life easy...
Build a mold ( you have the wood tooling) and pour a plaster cast.
One piece simple and lighter

It might be interesting to try. I have my doubts as to how well I could pull this off given how thin this is. I might want to embed the handles rather then form them.

Melamine form, Concrete, sand, maybe a fiberglass mesh given the thickness.

[mkovalcson]

I finished making the custom communication wires to make it easy to remove the Dual PL8's.

The wiring is complete and I just need the actual BUMP controller to decide where to notch the BUMP tray for the cables feeding it.

I ended up with 17",19",23",25" lengths. They are made from 20ga wire that I typically use for my ESC cables. Hopefully the extra thickness will make sure the serial communication works well.

[mkovalcson]

Waiting for the BUMP, but testing the current draw.

The 48V 2kW PS has a variable speed fan and you can tell as each PL8 starts to charge, but it is still much quieter than the Meanwell 1000W SE in my other Charging unit.

The Power Factor stayed around 98-99% the whole time.

My wall voltage is 121.5 for this test.

At rest the PS and 4 PL8's drew .31A without the Bump.

Each new 6S battery charging at 5A added about 1.20A from the wall.

So the whole system drew a maximum of 5.25 A with 4 x 6S batteries charging at 5A each.

Based on that I think the combined system (Generator, cables and PS) should handle a 2C charge with 4 x 7S batteries pretty well which is something I expect to do a lot this Spring. I also expect to have 12S sticks charging in parallel frequently at the airfield.

My plan is to charge each battery individually at 1C at home before hitting the field. Then I'll probably use 1 or 2C at the airfield charging sticks in parallel.

[mkovalcson]

There are centered keyholes 2" on center and 1.5" from the front of the BUMP controller to the final resting place.



Added a few notches to match up with the cables.

Now witness my fully operational Charging Station

[RevoKelly]

I think that Bump Controller is beaming with evil pride

[mkovalcson]

So far I have to say this seems very well thought out and seems to be working beautifully.

I've set up 5 x 6S batteries and 2 x 12S sticks so far.

The only sticking point I had was the numbering. I had the servo cables labeled with dots, but I had rotated my PL8's when I put them in.

The BUMP communication ports 1,2,3,4 have to match the PL8 extension numbers which I assume is a safety precaution so you aren't accidentally operating the wrong charger on the wrong battery.



The Display is very nice and I like the color coding.

When a charger is finished it beeps and that tab turns green.



When you click on the tab it stops beeping.



I decided to number my Chargers just to be safe.

[mkovalcson]

I gave my charging station a bit of protection from the wet grass.

It's not pretty, but it just Velcros in place and if it gets muddy I can peel it off at home and hose it off.

I chose 1/8" ABS to keep it light and used a heat gun to bend the edges over. It's not quite to the same finish level as the rest, but it will serve its purpose.



There are still a few parts that should be stained, but I've decided not to put a carry handle in front. I don't think it will matter enough and I think it would reduce visibility of the BUMP controller.

I'm looking forward to the Android app, so I can just peak at my phone while I'm at the airfield to check the battery charging status. I may use the tablet more at home, but I'm actually curious how much use it will end up getting.

[mkovalcson]

Originally Posted by RevoKelly

I think that Bump Controller is beaming with evil pride

I'm really liking the BUMP a lot.

Congratulations to everyone who has been involved with its creation