Weipu SA/SF 20/28 motor phase connectors

[Linesflag]

So there was some discussion and questions around my usage of Weipu SA20 as phase connectors in one of my boards. These are officially rated at 25A, which seems quite low at first glance. This caused some discussion about safety concerns due the connectors overheating.

I haven’t seen anyone else running these as phase connectors, so I went out and did some testing today. I have a small hill climb in my vicinity, about 1km long and ca 60m in hight difference (according to google, it sure feels like more). Nothing too crazy, but good for testing.

The track:

Ambient temperature was 19°C, so the motors got a bit toasty.

Amb. temp:

I did 3 runs, and after each run I unplugged one of the motor phase connectors and checked if they got warm or even hot. I don’t have a flir or anything, so you’re gonna have to trust my fingertip feelings here, but spoiler alert, they did not even get warm. I’d call the temperature ambient, if anything.

Here’s some data:

First run:

Second run:

Third run:

I was pretty much going balls to the walls on the track, considering the ground wasn’t that smooth and I had to watch out for people and biker. You can kinda see my improvement with the increasing avg. speed. All runs were done back to back, with no downtime or cooling in between.

The connectors have a metal casing, which kinda improves heat dissipation, although there is still a pretty thick plastic insulator in there.

All in all I’d say that these connectors have a lot of calculated headroom, I was averaging 38-41A battery amps going up there. I don’t have a metr so I can’t say anything about average motor amps, but if somebody wants to do the math, I’m running 12S with 190kv motors, 1:3.3 gearing.

If there’s demand I’ll do some more testing on a more brutal hill climb, there are some around here. If you have feedback on how to improve testing, feel free to tell me. Thats it, thanks for the attention. Tags for involved folks: @jack.luis @Battery_Mooch @b264

Bonus pics:

[tech.shit]

@Linesflag

If there’s demand I’ll do some more testing

I’m not tryinna demand it but I really want to see these connectors pushed to 60A @ 50V even for just a minute or so

[Linesflag]

That has likely already happened. Can’t prove it though, I’d need a metr.

[Vanarian]

@Linesflag

Weipu SA20

That’s coaxial style connectors style used in e bikes?

How about one of each per phase instead to raise ampacity?

If my memory serves right its been discussed on endless sphere that this was not optimal because kinda undesized for some high power builds.

Glad it works good enough for you tho.

[Linesflag]

Well you could always use the SA28, that’s rated for 50A. I’m sure that’s plenty for most boards, idk about bikes though.

@Vanarian

How about one of each per phase instead to raise ampacity?

There’s not enough space for that, and costs would be through the roof. Those connectors aren’t exactly cheap.

[Anubis]

What’s the advantage over MR60? (Or MR60 with glue heatshrink over it I guess)

[Vanarian]

Reminds me of the Rosenberg RoPD magnetic connectors, great build quality but cost is kinda prohibitive!

I think these were also rated for 30/40a?

I still have a unused set of Demo kit with all the lineup they had 3 years ago.

[Linesflag]

@Anubis

What’s the advantage over MR60?

MR60 tend to vibrate out of there sockets, these are self-locking. That and they look way cooler. Disadvantage is the price, these are about 15x the cost of a regular MR60 connector pair.

@Vanarian

Rosenberg RoPD magnetic connectors

I think Weipus are nicer because of the metal construction, but yeah, same story.

[xsynatic]

@Linesflag

MR60 tend to vibrate out of there sockets

[Linesflag]

I use them in one of my boards and from time to time I have to push them back in. There is a bit of cobble around here, maybe that accelerates the process a bit, but it has pushed me into looking for locking alternatives as the above mentioned.

[xsynatic]

I use 'em on my MTB and Hub board they’ve held up just fine so far. No adjustment needed.

Have you tried expanding the prongs to make it tighter?

[Linesflag]

@xsynatic

Have you tried expanding the prongs to make it tighter?

Nope, I just noticed them slipping out like .5mm per ride and started thinking about locking alternatives. Maybe I got some that are a bit on the loose side.

Then again, I talked with @mackann (I think?) about MR60s and I believe he has experimented with 3dp locks on them, because of the same issue. Don’t quote me on that though, thats like half a year ago.

[xsynatic]

Other alternatives are a ziptie around them like many do with xt60/90 or a dab of hotglue.

[Linesflag]

Sure, or a 3dp lock like mentioned. But then I found Weipu and those are like infinitely cooler. Definitely the more expensive solution lol

[mackann]

Yea we use it :

[tech.shit]

I thought you guys used cnlinko connectors?

[Linesflag]

The 3 in the middle are cnlinko

[tech.shit]

ahh I misunderstood the exchange there