CLyte 48v 25a controller, can i push the amps up a bit

[Steve Wells]

Hi guys.
Built 2 bikes now and learnt a lot in the process.

My first build was a bafang 36v 500w motor, so i foolishly assumed at 50v it was drawing around 10 amps.

So when i ordered my ht3525 i thought that buying the 25a controller and an apm was going to give me at 25a, upto 2.5 times what the bafang was putting out. loads i thought. ho ho ho

Having looked at ku123 bafang controller it reads max draw of 30 amps, so i guess its running at a peak of more like 1500watts at 50v

so my question is.... knowing it will void warranty how far do u think i can push the amps upto on the crystalyte brushless sensorless 48v 25a controller before risking damaging it.

And the volts too i guess (currently got 2x6s 6000 lipos) might add a 2,3, or 4 if poss.

they should be 44.4v i guess but apm reads 50 when charged.

Thanks guys.

 

[Steve Wells]

Anyone, before I pop it

 

[wesnewell]

Well, just raising the voltage will increase wattage along with max speed. 25*50v=1250W. 25*60v=1500W. A 33% shunt mod should get you about 33A and should be pretty safe unless you ride it really hard. I upped my 30A controller to 42A over a year ago and it's still going strong.

 

[Steve Wells]

good stuff, does the shunt mod increase amps regardless of what its set too. or does the extra shunt just allow u to up the amps safely. Hope that makes sense
thanks
Steve

 

[dogman dan]

Well, much depends on what you call safe. For sure, you can up the amps a tad with a shunt mod, and it will "last awhile" How long awhile is would depend entirely on how you ride it. Long enough for the new controller you definitely will be buying to get here for sure.

So I'd say, go for it, and put a small blob of solder on the shunt, ride it, then add more if you aren't getting 30 amps yet.

As for overvolting, your theoretical absolute limit is 63v, due to the 63v caps inside. So I wouldn't hesitate to go 14s or 15s RC lipo voltage. Around the block once or twice, and you will be back into the below 60v safe zone. Or charge to 4.1v, whatever.

Fairly obvious though, that what you really want is at least a higher amp 48v controller if not a 72v unit. So start working on funding that. I see 18s RC lipo in your future for sure.

 

[dogman dan]

One last thing, you may well be seeing 1000w on your current setup. The reason you don't see more is because it's not stalling and making heat like the little motor was, if you fed it too much power up a hill. So very likely you are seeing more power at the tire than you did with the little motor. Your choice of the HT was wise, it will make less heat climbing a hill, or starting off from a stop sign than the HS would. But to get the lower speed windings to pull a lot of watts, will take a pretty darn steep hill. Watts drop off faster with the lower speed windings, since they get closer to thier cruising speed sooner.

Or, as I've been alluding to, offer it more volts. It may still only pull 15 amps, but your 15 amps will be x 75v fully charged, vs 50v fully charged. So you should see above 1000w, even if it's only pulling 15 amps. And of course, when starting up, a 30 amp spike would be about 2000w.

Slow motor and relatively high voltage has been the happy combination for me. Just go to 18s and you'll be grinning, I'm sure of it. Meanwhile, go ahead and solder the shunt, but it won't make the motor draw more amps at cruise, or increase your top speed much. More volts will be the answer.

 

[Steve Wells]

Thanks for your reply Dogman. All makes good sense.

Crystalyte make a 72v 40amp controller, do you think that wil be best bet.
I will need an apm connection to program the controller.
But i hav heard of a few controllers on here.
Is it Ecrazyman, and or lyen.?

Dont want to make hard work for myself with connections and compatibilty.

Steve

 

[wesnewell]

good stuff, does the shunt mod increase amps regardless of what its set too. or does the extra shunt just allow u to up the amps safely. Hope that makes sense
thanks
Steve

It just increases potential. How many amps it uses depends on how you twist the throttle and how steep the hill is. About the only way to use max amps is put the bike against a wall and go wot. If you do a shunt mod, wrap the shunts with wire and then put solder on. Don't just blob on solder. Doing that leaves the potential for the solder to melt under heavy use and that's not good.

 

[Steve Wells]

Ok think I got all that
One last question then..
I have an apm which allows me to increase/decrease amps, lvc etc.
Is there any difference between soldering shunt as opposed to just increasing amps via the apm.
Thanks

 

[Drunkskunk]

The melting point of solder is around 420'F, And the shunts are held to the circuit board by solder. If you get the shunt so hot it could melt off your solder, you have already melted your wiring, and are doing significant damage to the controller.


I believe The APM gets it's information the same way tje CA does, using the Shunt in the controller. If you modify it, you will throw the APM off. I don't know if it can be recalibrated.


The best way to add solder is with a single drop at a time. it doesn't take much to achieve results.

 

[dogman dan]

Sounds like Wes has heated up a controller at some point pretty good. Do the shunts get really hot if you put on a lot of solder Wes?

I've been liking my Lyens controllers. I have the 12s one in 60-90v and 90- 120v both set to 40 amps. I also run a 9 fet 72v 20 amps one. Thrifty with the wh, but still allows good speed that one.

Others have found very similar stuff to the 12fet controllers for very low prices. I just liked supporting Lyens because he's a really outstanding guy.

 

[wesnewell]

No, I've never heated one up much at all, but I did read somewhere that someone got it hot enough to melt the solder and it flowed and shorted something out. 99% of my riding is at 10-12mph pedaling along with the motor to get some exercise. But when I really want to go somewhere, I want to get there in a hurry, so that's why I run higher voltages.

 

[dogman dan]

Ahh, I see. Perhaps one of the folks running 5303's. Those were notorious controller blowers. They'd pull huge amp spikes.

I don't recall anybody running a smaller motor having the solder on a shunt melt.

 

[Steve Wells]

Added a 3 cell today so I'm now running 15s 63 volts fc.

I upped the 25a controller with the apm to 28 ( roughly 10%), so the 48v 25a crystalyte controller is now at 63v28a.

Everything still runs cold, and I'm wondering wethr the stock controller would cope with me pushing upto 30 amps as I reckon at 60v that will be enough for me.

Thanks
Steve

 

[Drunkskunk]

There is always some risk in pushing things beyond their limits... But I wouldn't sweat pushing it to 30 amps if it was my own.

 

[Tench]

Hi Steve, i run the HS3540, a very similar motor to yours, same motor slightly faster wind on 18s RC lipo (75 volts charged) through an unmodified crystalyte 72v 40a controller, it peaks at 40 amps and 3000w and goes very well, if you push yours too far and it fails or you want a little more than it can give go for one of these, perfect for your motor.

Simon.

 

[Steve Wells]

Yep I think that's the answer Simon. Thanks everyone for your input.