Help! Bus Bar for HV Multirotor

mountaindewdude76

Junior Member
I hope this is ok to put this question in this part of the forum. I'm not sure where to specifically put this.

So, I am anticipating a rather large multirotor build in 2019. I have my motors and props picked out and I'll be using a 12S lipo configuration. The specs for the motors state a max of 80amps on a 14S setup. I will only be running 12S. I have found some 100amp esc's.

Now, I've been hearing some people are using bus bars, for power distribution, instead of a PDB. I was thinking about doing this and still using a lower voltage PDB for the LED's, vtx, camera, etc.

So here's my question....how do I go about building a suitable bus bar to handle the 44.4v and 80+ amps? Honestly, it's not likely that I will fly "full throttle" for very long, so I won't be hitting those high amps but I'm just concerned about the possibility of heat being produced and would be any possibilities of melting the bus bar connectors, etc.

Does anyone have any thoughts? I'd be most greatful!

Derek
 

mountaindewdude76

Junior Member
ok, thanks for the reply.

Now, I am no electrical genius. How would I go about wiring up a bus bar? Wouldnt there be two bus bars, one for positive and one for negative? The battery connects to one side of each bar and then the positive and negative leads from each esc would connect to the bus bars as the voltage output. Is that about right?
 

ElectriSean

Eternal Student
Mentor
Now, I am no electrical genius. How would I go about wiring up a bus bar? Wouldnt there be two bus bars, one for positive and one for negative? The battery connects to one side of each bar and then the positive and negative leads from each esc would connect to the bus bars as the voltage output. Is that about right?

Correct. I would solder my leads directly to the bus bar. You also have to think about how to mount it while keeping it isolated. A 3D printed mount or nylon standoffs would work.
 

CarolineTyler

Legendary member
Solid copper seems very difficult to work with - why not use larger gauge multi-strand copper wiring, more surface area to conduct and far easier to join.
 

FDS

Elite member
When soldering direct to copper bar/plate you need a really clean surface, a separate flux and a 40-60w iron, the biggest problem is how fast it draws heat away from where you are working! As noted wires have some advantages, generally a higher strand count and greater cross section are desirable.
I use silicone insulated multi strand wire in 10-18awg for high load work, it’s easy to splice into and is light and flexible. A decent 12AWG with plenty of strands will be able to take the current loads you are looking at, check for a proper data sheet when buying wire, as that should state it’s current capacity. Be sure to insulate all splices with heat shrink tubing.