Any tips on Vedder Anti-Spark switch?

[cdn]

thread revival (my own so i think i'm allowed)...

Got some cool LED switches that need 12v to light up.

Can find some BEC's that output 12v, but most are limited to 6s max. I'm hoping to use this on some of my setups with possibly 12s. Any thoughts or suggestions on how best to do this?

worst case i can leave it unpowered/unlit. Work but boring.

What about a step-up converter from 5v to 12v? Grab power from VESC 5v power output that goes to Rx?
Found a small 1.25A max output (plenty):
http://www.amazon.com/power-module-3-5V~10V-Output-version/dp/B0043BBXT4

Appreciate input and thoughts on best way to do this!

Not too sure if this helps. They do make a SBEC that is made for 2-13cell lipoly. It has dual voltage outputs 5A/5v and 10A/12v. I use this SBEC to power my automotive accent lighting on my boards. Its currently available at Hobby King (east). Its a Turnigy Multistar Twin Output SBEC.

 

[izeman]

Yeah ... I guess some strong current will be flowing in the PCB.
Maybe Vedder knows better how thick we should plan the copper .

you can just add some solid copper wire to the pcb and be safe.

 

[izeman]

btw: if you only want to power this little 20mA led you can take power from the first 3 cells in series and you're done. it will not make your battery going out of balance as the load is so little. you will pull 40A by the motor and 20mA by the led so this is 2000:1.

 

[sl33py]

Thanks for the good ideas! I'd hate to unbalance my cells if there is a simple way to do this otherwise. Either with the step-up converter or the 12/13s UBEC linked.

I got a few extra boards made when ordering, and they included a couple extra for free (kinda cool of them!). So when i ordered the components from mouser i have enough to make them minus wire and fuse. If anyone wants one PM me and will sort out a fair $ to send you everything you need (minus fuse and wire):

I need to get some of the slow-blow fuses (i think regular work too). Might stop at auto parts store tonight on my way home to finish this one.

EDIT - not looking to make a profit. Some $ for my time and will donate $ to Vedder since it's his work!

 

[torqueboards]

These are cool.

 

[sl33py]

These are cool.

Got one of those for a board. Nice and simple. But think i'll also try the fuse on this anti-spark power switch he built. Vedder is the man!

 

[elkick]

These should work as well. To be soldered on the PCB and containing a standard ATO fuse.

 

[izeman]

i do NOT recommend those fuse holders. they may be ok for low current. but no for 50A+. the spring contacts are vwey weak and after some time they became so lose that i had sparks inside the holder. better to solder the fuse directly inline and have a way to bridge the switch in case a FET dies.

 

[sl33py]

i do NOT recommend those fuse holders. they may be ok for low current. but no for 50A+. the spring contacts are vwey weak and after some time they became so lose that i had sparks inside the holder. better to solder the fuse directly inline and have a way to bridge the switch in case a FET dies.

Thanks izeman! That makes sense to me. I was thinking i might look for some small copper i could fold over and solder down, then slip/press-fit the fuse into. Not right away but maybe down the road. I also like your idea if something fails you can bypass - might add some simple bullet connectors and tape replacement lengths w/ the same connectors to bypass if fails.

Great ideas! Soldering mine down for now.

 

[sl33py]

For Sale thread for extras:
https://endless-sphere.com/forums/viewtopic.php?f=31&t=73800

 

[akiraEC]

I am a bit worried that a single module would not be reasonnably sized for a dual diagonal.

I have two 10S/4000mAh batteries (in paralel ... obviously).
I woud put one on each battery and wire them parallel after the antisparks.
Does this sound OK ?

 

[sl33py]

I am a bit worried that a single module would not be reasonnably sized for a dual diagonal.

I have two 10S/4000mAh batteries (in paralel ... obviously).
I woud put one on each battery and wire them parallel after the antisparks.
Does this sound OK ?

I have done some testing and usage w/ the inline watt meter. I have seen peak Amps around 65A w/ dual 50mm motors w/ dual VESC on 8s. I am following Vedders original recommendation of a 40A car fuse which shouldn't blow for a brief over amp situtation. If needed i might swap to a 60 or 80A fuse if my next dual setup needs higher Amps (but on higher 8/10/12s it should have lower amp draw). I'm also going to try using an eagletree logger so i can see not just the peak, but average amps.

I'm rethinking my setup slightly with this switch. I might use bullet connectors and include a short length of wire to fully bypass on-the-fly if any issues. When i have logging and all the info to make an informed decision then i might skip the extra wire backup.

Worst case it blows the fuse. Not easy to swap on the side of the road, so i would definitely have a bypass until comfortable the fuse is sized correctly. You can swap the fuse w/ your iron in a few minutes and fuses are relatively cheap.

I am still going to look at a small piece of copper bent over to press/hold the fuse in place which would make it easy to swap. something about the size of the contact pad - double the length, fold it over with an arc so the end comes down to contact the middle of the contact pad perpendicularly - 90* like so: __|__ . Could round the front edge to get the fuse to slide in easier. With a couple cents of copper and some time i think this should work. I might have a small loop of electrical tape to hold the fuse in place as insurance. If i get it sorted i'll take a pic and share. Small fiddly pieces, so might not look great, but if it works like i imagine it'll make swapping fuses much easier.

HTH!

 

[akiraEC]

Yeah ... thanks for the inputs !!
I have bought an eagle tree and hope to get some measurement ... when my setup will be finished.
The Antispark was the last bit of real hardware missing.

 

[jamesonotc]

do you know if I need a high voltage high amperage switch to use the anti-spark pcb or will it work with any plain switch?

 

[chaka]

Anyone using this on 6s will likely have some issues with mosfets desoldering or shifting when hill climbing or other high throughput events. I think I have singled out the issue being insufficient current handling of the traces.


I made a few revisions to the gerber files and doubled all the traces and have some pcb's in fab for testing. I'll keep everyone posted once we get some results.

OshPark Files: https://oshpark.com/shared_projects/XuqJkZzU Please note this is not officially version 1.4 of Vedders pcb design. I just needed to keep my oshpark files organized.

We also have another more robust version of the switch is in the works and I will post the files once I have completed the pcb design on KiCAD. It will feature pads for soldering proper shunts and possibly heatsinks if needed.