Controller Overheating

[s_t]

My controller, after 10-15mins or so of riding (the longest I've done so far), is getting rather hot. I can't hold my hand/finger on it for any longer than 1-2 seconds. It still works, but I'm concerned something is going to go up in smoke soon.

My system is as follows:
- 36V 15Ahr Ping battery, which seems fine and doesn't heat up at all
- 36V 350W Keywin/ecrazyman controller (as advertised - doesn't have a sticker on it to confirm this), with regen.
- Yucheng geared (no freewheel) motor. Was advertised as 36V, 250W, but bought used and I'm unsure as to whether seller really knew details. Hub gets warm.

Unfortunately I don't have the means to measure current at the moment. Top speed is around 26-27km/hr (16-17mph), which seems a little low for 36V, but perhaps the geared motor is wound for slower speed.

I haven't finalised the controllers position yet. So far it has just been sitting on top of the battery. Not great airflow, but not enclosed either. Whilst it isn't positioned ideally (and I will fix this up), I don't think position of the controller is the primary cause.

The 3 phase wires on the motor are rather small. A lot smaller than the controllers, which are a lot smaller than the batteries! About 2mm (0.075") overall diameter including insulation!

Any comments on what could be causing the controller to overheat?
Thanks.

 

[dogman dan]

Most controllers get hot, but are designed to shed the heat. Mabye it's too small to have good heatsinking properties?

Back when I ran brushed, my tiny little controller would always be pretty hot. Summer where you are?

 

[s_t]

Thanks. Yes, it is summer here and fairly hot - Brisbane, Australia. The controller stayed untouchably hot for probably 5 minutes (after stopping), which is what has me concerned.

I was thinking along the lines that the motor and its small wiring might be providing higher electrical resistance, which would increase the current and make the controller work harder all the time. Then I realised I had ohms law the wrong way around and the current would be lower - making life easier for the controller.

I could put a heatsink on it (and will mount it in a better place). I will trial a few things.

In the meantime though, doesn't sound like there are any other issues I should look into?

 

[dogman dan]

In summer, that is most likely normal temps then. I like to mount controllers to the front side of battery boxes on my rear rack. They get some wind, and the metal box is somewhat an additional heatsink. In midsummer, my controllers get pretty hot too, in 95-105 F temps. Of course, if I'm wrong, you'll know when the smoke comes out. But I think you are operating normal for a hot climate ride.

 

[velowatt]

I have been mounting the controller in a bag with a small cooling fan from a computer power supply. Recently, I put all the electronics in a hard shell case ("Octivia box") that mounts on the back. The battery (48V 10Ah) drives a pair of small DC converters- one for 5V that drives the cooling fan, one 15V DC that drives a dual LED headlamp. I can also charge my phone or run a small stereo. I got the converters from a surplus store for $4. I don't know if its overkil, but the controller stays cool! I seem to have a bunch of these fans sitting around from junked PC bits that my kids acquire and leave laying around...

 

[s_t]

I noticed the controller got quite hot (but not untoucheable) with the drive wheel at full speed under no load (well, just the 26" rim and tyre spinning in air). So, before forgetting about this heat issue I have done one last check.

Current under no load conditions, at full throttle, is just shy of 8 amps! I'm no expert, but that is excessively high is it not? I think I've read it should be about 2 amps somewhere?

Put some load on it by rubbing the tyre on concrete (enough to slow motor down), and load increased to about 11amps.

What is the next step here? Checking hall sensors or something else?
Thanks.

 

[s_t]

I've just being playing with phase and hall sensor configurations. I've found one that uses only 1 amp full throttle, no load!

Appears as though I'm lucky to still have a working controller given how it was!

Amazing thing is that the old config, that used 8 amps no load, ran fine. Just used a heap of juice! I can only just tell that the new config is slightly smoother, and no way I would have picked when it wasn't wired correctly (if it weren't for the heat & amps).

I'm keen to go for a ride again now - might have more power and top speed 8)

 

[dogman dan]

Shoudla read closer, yeah, you had to find the connector configurations yourself. I woulda thought a wrong one would have run noticeably crappy though. Learn something new everyday here. Any chance you were running in reverse or something?

 

[Almasi]

To fix the heat generated by your controller, you could simply change the Mosfet to IR4110 their low internal resistance will create much less heat and waste less energie!

Robin

 

[s_t]

That's fine - nothing broken and hopefully problem solved (haven't yet taken it out riding - been raining :x ).

To an experienced E-biker, perhaps it would have been noticeable. To a first timer it seemed great - took off from start fine and reached and held 26-27km/hr easily enough. It was running forwards and is still running in the same direction now.

The more I play with it, the clearer it is that it is smoother and slightly quieter now, and has more pulling power. Maybe the problem would have been more noticeable earlier if it were a higher powered system.

Shoudla read closer, yeah, you had to find the connector configurations yourself. I woulda thought a wrong one would have run noticeably crappy though. Learn something new everyday here. Any chance you were running in reverse or something?

Thanks. I'm not experienced with electronics, so I'll trial the new config and see how it goes heat wise before making any changes like this.

To fix the heat generated by your controller, you could simply change the Mosfet to IR4110 their low internal resistance will create much less heat and waste less energie!

Robin

 

[Knuckles]

s_t,

You had the WRONG phase/hall wire combination. Thus the excess controller heating.
Fortunately you discovered your blunder and corrected it before causing serious damage to your equipment.

Shame, I had spelled out the answer over a year ago on my threads.
Yet ... All's well that Ends well.

Glad to see a "noob" solve his own problems.

PS. Time for you to contribute. Post some pics. Post your newly found "correct" wiring.
It matters.

-Knuckles

 

[s_t]

I wouldn't have worked this out without the great info here. I spent some time reading the phase/hall wiring combination threads (and related).

Its a pity it worked straight out of the box - with the wire colours matching. It meant I thought it was right, without trying other combinations. I've just been for a 30min ride with the new combo, and the controller only went slightly warm!

Motor - Yucheng SWXJ, geared, no freewheel
Controller - ecrazyman 36V 350W

Correct combination:
Phase: Motor-Controller
B-B
G-Y
Y-G
Hall: Motor-Controller
B-B
G-Y
Y-G
Pos-Pos
Neg-Neg

I'll add this to the known to work wiring diagrams thread.

I'll post some pics and details of my build sometime somewhere else

s_t,

You had the WRONG phase/hall wire combination. Thus the excess controller heating.
Fortunately you discovered your blunder and corrected it before causing serious damage to your equipment.

Shame, I had spelled out the answer over a year ago on my threads.
Yet ... All's well that Ends well.

Glad to see a "noob" solve his own problems.

PS. Time for you to contribute. Post some pics. Post your newly found "correct" wiring.
It matters.

-Knuckles

 

[Knuckles]

Awesome ...

You have demonstrated my "blue 2 blue" rule.
ecrazy xie-chang 'ish controller with Bafang 'ish like motor. Cool!

Blue 2 Blue ... Switch the other 2.

Anyway ... Thumbs up 2 you ...


http://endless-sphere.com/forums/viewtopic.php?f=2&t=9891

8)

PS ... NICE STEEL GEARS ON YOUR Yucheng MOTOR!!! ... I LIKE!