GoldenMotor.com Forum

General Category => Magic Pie & Smart Pie Discussions => Topic started by: Pwd on July 19, 2016, 02:27:13 PM

Title: Magic Pie 2 wire slot size
Post by: Pwd on July 19, 2016, 02:27:13 PM

Hey guys, I would like to convert my Magic Pie 2 to an external controller. Currently the slot in the axle fits a bundle with an outer diameter of just under 6MM (5.90 MM). I'd like fit new phase wires and hall sensor wires through the same space under the original bearing but I can only find something like this which has an outer diameter of 9MM:

http://www.ebikes.ca/shop/ebike-parts/wiring-accessories/grinmotorcable.html

My new external controller is capable of 40 amps so I need the phase wires coming out of the axle to be able to handle that current for at-least 30 seconds.

I don't think I can enlarge the slot without severely weakening the axel. Has anyone else tried this?

Thanks

Title: Re: Magic Pie 2 wire slot size
Post by: Morgen 3Eman on July 19, 2016, 05:23:38 PM

If you cannot fit a larger wire size, make the connection from the feed thru wires as close to the axle as possible.  Wire size amp ratings are usually adjusted to reflect the distance from the source to the load.

TTFN,
Dennis
 

Title: Re: Magic Pie 2 wire slot size
Post by: Bikemad on July 19, 2016, 11:30:17 PM

Three separate lengths of 12awg AlphaWire EcoWire (http://www.alphawire.com/Home/Products/Wire/EcoGen/EcoWire/6718) which has an outside diameter of ~3mm is what has been successfully used in the past for MPII phase wires with external controllers. 

Network cable, or part of a ribbon cable, is commonly used for the five Hall sensor wires if you're not using a sensorless controller.

(http://www.arhservices.co.uk/GoldenMotor/MP2LHbearing.JPG)

The space for the cable is very limited, so size really does matter.  ;)

Alan
 

Title: Re: Magic Pie 2 wire slot size
Post by: Pwd on July 21, 2016, 12:34:48 PM

Thanks for the insight guys. I like the network cable idea for the halls and it sounds like the shorter I keep the phase wires coming from the axle; the safer it will be.

Title: Re: Magic Pie 2 wire slot size
Post by: Pwd on August 08, 2016, 12:27:11 AM

I finally got around to wiring my Magic Pie 2 for use with an external controller. I used some scrap network cable which was luckily braided vs solid wire and I used some of this for my phase wires:

12AWG with a 2.69mm outer diameter - a bit smaller than the EcoWire but I really wanted it to fit through the existing slot.
http://www.digikey.com/product-detail/en/te-connectivity-amp-connectors/99M0111-12-0/A119542-ND/4898330


After soldering on the new wire etc... I hooked everything up on the bench and it lives! 8) My next test will be to try the wheel in an old fork to see how well it spins. I am also going to have to get some custom torque arms fabricated before I use thing on a bike.