Main motor wires on external max amps?

[Spacey]

I'm looking at the 3 main power leads for the External controller powered Magic Pie wheel and wondering how many amps I can give those 3 wires before they damage?

They don't look very big at all but then again they are not your standard type of wire so might be able to take some big amps?

Anyone have a clue?

Also why don't they have the main power wires coming out of the left and the hall sensor wires coming out of the right of the wheel, that way you could have thicker main power wires

[Bikemad]

The phase wires will probably take the 40 amps max that your controller can supply for short periods, but if they start to get too warm during prolonged hard use, then ease off on the amps, because I suspect the windings inside the motor will be getting that much hotter again.

I guess it's easier to just have one set of wires to deal with, and also there's no chance of damaging to the wires if the chain comes off.

Using a sensorless controller would eliminate the need for the thin hall sensor wires altogether.

Alan
 

[Spacey]

Cheers for the reply, though I do have to say the actual MP motor stays remarkably cool even when I've been hammering it with over 40 amps up a steep hill. The wires were warm to the touch.

I think the wiring is too long as I have to double it up to get rid of the slack, about 3 to 4 feet of access wire, shortening that might help.

[MonkeyMagic]

Hey mate, definitely keep your wires as short as possible.

Also, do your best not to coil or wrap any power type cable as this naturally generates heat and causes a loss.

Even have thicker wire goto as close to the wheel as you can get it; then make really good connections to that.
8AWG cable I think is a good size and would not get hot. Of course you can't fit that into your wheel axle though Maybe have the 8AWG go into a screw terminal or big connector to then downsize to the 12AWG you are using going into the wheel.

I think a good mod is upgrading the wire gauge of the both the battery and phase wires if you are using an external controller.

With my dual drive and battery setup both being internal, I want to run 8AWG for gnd & + from my battery pack(s) as close to each wheel as I can.I just noticed tonight I know this would make a massive difference.

Anyways hope it was a good move going to external

Cheers

[Spacey]

I think you are right, but man that's a pain in the arse job to do lol.

Think I'll use some big fat amp wire right up to the axle connector. It looks like a skinny girl with lots of hanging skin after liposuction all the spare wire I have.

It is doubled back on itself, how much of a heat loss difference would it make?

[MonkeyMagic]

Hey dude

When you say 'access wire' for the phase cables what exactly did you use? If you have the AWG size would be better.
I just got a length of 12AWG through Alphawire, courtesy of the mention from Mark [Scorpion] who has presence here. Cheers Mark!

It's exactly what he said, super thin high guage wire that will support the current from a 40Amp controller no sweat.

When you say the lengths, you can calculate the loss/resistance but I can't be bothered finding my numbers hat.

All that I know is rule of thumb, anything with power and that over 2+ Amps should never be wrapped as this naturally causes the wire to turn into a small heater. Much higher current and you can potentially start a fire. We are talking about a bicycle here, so even with you 'doubling up' I higher doubt there is any loss at all unless you are using inferior cable. Better to be safe and have peace of mind though...

The heat is also caused by the wire maxing out its holding current. All I am going to do is fit a IEC connector:


^^ as close to the wheel I can and use a plug and socket for it. As for the hall sensor wires, I will just use a IP65 rated DIN plug/socket. I'll mount the controller as close as I can to the wheel, then the battery close as I can to the controller.

Will be trying to use 8 or 10AWG from the battery to controller, then from controller to socket. The wheel will then plug in with the 12AWG Alphawire keeping resistance at a bare minimum.

So the blurb of the novel is "Use as high gauge wire as you can where it fits" without going overboard.

Hope that above mess helps you a bit lol


Saves a massive pain in the ass if you have to change a tire etc.

[Spacey]

Damn good idea the plug thing

The wire I use is just the wire that comes with the Infineon 40 amp controller which then connects the the thinner wire from the MP wired for external controller which has abour 4 ft of wire.

I would say I've gone from the handle bars to the seat.... back to the handlebars then back to the seat end to tidy up the access wire.

[MonkeyMagic]

Gee okay then well you probably want to change that.
You are lucky I guess you were prepared to wire up a canoe lol

Anyways I'm not sure if soldering scares you but you really want to shorten those, possibly add a plug/socket arrangement.

Perhaps ask yourself "how long am I going to ride this frame" if it is like 6 months or so then maybe choose to leave it be, but if you want that ride to last then you want to neaten up those cables.

When I wired my recent bike, I made all of the cables a bit longer than I knew that I needed, then I trimmed them down as I connected them. When you are dealing with high gauge wire you really want a 60W+ soldering iron because anything less will either take ages to adequately heat the wire and generally does not end up with a good connection.

You will thank yourself a ton once its done.