x-byke controller help

[aseb]

My x-byke decided it would go no further after a trip out during the snow. I've done my checking and it is the controller. R21 has fried itself. Does anyone have a circuit board diagram, or know the resistor value/wattage?

The board is £60 + carriage from powabyke. However I'd like to attempt a repair because of this price (and something else I'm in the process of doing, apart from the cost of christmas).

I can't read the value because the heat has damaged the colour bands. It is the big older style resistor at the side opposite the wiring entry (the R21 marking can't be seen until the resistor is removed but is the only traditional (non-SMD) resistor), it's on the board edge and is about 14mm long by 4mm diameter so probably 3W. The colour of the bands would do if anyone has one they could look at.
Other details on the controller are AK0806180015 AND 36Y-18AP.

Thanks

 

[rog_london]

Just from your description, I'd be inclined to think that the fried resistor is a symptom rather than the cause - I'd guess its purpose is to act as a dropper for the regulator which provides power for the rest of the board, and either that or something else has shorted - which you won't be able to fix.

Rog.

 

[NRG]

A clear picture would help, I agree with Rog sounds like the dropper resistor for the 5v regulator, on the XieCheng controllers about 60mA flows through this resistor dropping 18v or so (300Ohm), if its got so hot as to burn then something else is probably wrong. Not easy to fix unless you know what you are doing. Xiecheng controllers can be bought from E-Crazyman for under £20, you may just have to match or change connectors...

 

[Patrick]

If your bike has one of the early controllers that insists on two unassisted pedal revolutions every time you let go of the throttle then the new controllers are a worthwhile upgrade in their own right, so it's not a complete disaster if you can't fix the old one.

I had to replace my controller in the summer and there have been two major improvements in the programming. My bike now only needs one revolution before the motor kicks in, and even better it doesn't reset as soon as you let go of the throttle, so when I stop at lights and junctions I get instant power when I set off again.

 

[aseb]

If your bike has one of the early controllers that insists on two unassisted pedal revolutions every time you let go of the throttle then the new controllers are a worthwhile upgrade in their own right, so it's not a complete disaster if you can't fix the old one.

I had to replace my controller in the summer and there have been two major improvements in the programming. My bike now only needs one revolution before the motor kicks in, and even better it doesn't reset as soon as you let go of the throttle, so when I stop at lights and junctions I get instant power when I set off again.

Thanks guys.

It is one of the first controllers with the couple of turns of the pedals needed.

Temporary solution- because it's a brushed motor I've connected the battery directly to the wheel via an on/off switch so at least I've got power on open stretches of road until I get things sorted. And the bike pulls more vigorously this way, it feels stronger up hills.

I really want to avoid getting a replacement controller- I'm looking to upgrade to a new controller/motor fairly soon. I've got as far as pricing but am baulking at the carriage costs for the wheel from the US. $180, £120 for hub only- but my local bike shop can't do a wheel build for me- I've started a new thread asking if anyone knows of somewhere that can help.

 

[NRG]

Like this one:

Endless-sphere.com • View topic - 36V 800W brushed speed controller - UVP 31V

This is from E-Crazyman (Keywin) on Ebay....

 

[aseb]

Like this one:

Endless-sphere.com • View topic - 36V 800W brushed speed controller - UVP 31V

This is from E-Crazyman (Keywin) on Ebay....

Nice clear pics, thanks for the link. That has 6 power transistors, the Powabyke only 3, and there's only one of those 3W resistors. Mine starts with a brown band, and has gold tolerance so I've little to lose by trying that resistor, possibly its associated capacitor (looks undamaged though) and transistor (again it looks ok).
Unfortunately my local dealer didn't have any controllers to look at but I think its worth risking a pound to see if that's going to sort it trying the same value as I've been unable to find details of the right one.

I tried a quick pic of the controller- resistor leg snipped to see any markings but it's a very poor phone pic, I couldn't find my camera.

 

[aseb]

I tried a quick pic of the controller- resistor leg snipped to see any markings but it's a very poor phone pic, I couldn't find my camera.

Best I could manage with the phone:

 

[Andrew harvey]

Try Sunlova or Alien for a replacement motor prebuilt into a wheel, then an E-crazyman controller, they both normally carry spares.

 

[NRG]

Not sure I can help, don't know the controller...somethings pulled too much current through the resistor over time....you may be able to just replace it but there's no guarantee that will work of if it'll just go again or blow something more serious later. What the value would be is anyones guess but I suspect lowish R value and about 3W.

 

[aseb]

Not sure I can help, don't know the controller...somethings pulled too much current through the resistor over time....you may be able to just replace it but there's no guarantee that will work of if it'll just go again or blow something more serious later. What the value would be is anyones guess but I suspect lowish R value and about 3W.

From the physical size it's a 3W resistor. I really only need it as a short term solution which is why I want a cheap repair. Maybe I'll look at variable resistors but I 'd guess that 3W ones will cost as much as a controller.

 

[aseb]

Try Sunlova or Alien for a replacement motor prebuilt into a wheel, then an E-crazyman controller, they both normally carry spares.

The motor is ok, it's just the controller. I'm really looking for a short term fix as new bits are on the horizon......

 

[Deleted member 4366]

What about this one?
36V 250w Controller Box For Electric Scooter Bike Al on eBay (end time 13-Jan-11 18:45:28 GMT)
No pedal sensor, but it least you can use the throttle. Maybe it has the same resistor. Does anyone know what that resistor does?

 

[NRG]

If it's anything like the E-Crazyman controllers (Xiechang) the resistor drops the battery voltage to a safe level for the 12v or 5v regulators that power all the control circuitry...

If you don't mind it blowing up completely you could try and replace the resistor with say a 220 ohm resistor or maybe start at 470 ohm and measure the voltage drop across it and work out the current draw. You'll need everything plugged in like the throttle etc to create a draw. I have no idea if it will work and take no responsibility if you explode or burn the house down!

 

[rog_london]

If you don't mind it blowing up completely you could try and replace the resistor with say a 220 ohm resistor or maybe start at 470 ohm and measure the voltage drop across it and work out the current draw. You'll need everything plugged in like the throttle etc to create a draw. I have no idea if it will work and take no responsibility if you explode or burn the house down!

That's sensible - and the 470 ohm resistor will drop a maximum of about 18 volts if your battery is a 24V one as a five volt regulator will have an 'overhead' of about one volt to two volts of its own. Into a short on the far side of a 'good' regulator you'll have a current of about 40mA, and a dissipation in the resistor of about 0.7 watts. If the regulator itself is shorted you'll have a current of just over 50mA and a dissipation of about one and a quarter watts. Therefore a 470 ohm 3 watt resistor would not burn out but would get a bit warm.

These figures lead me to think you probably had a much lower resistor value. You might like to try a 220 ohm ohm resistor. Into a short this would draw 2.2 watts. Even this would not, on the face of it, burn out a 3 watt resistor. Your resistor looks like it was 'gently' burned out, so might have been of an even lower value - perhaps around 150 ohms. If it had been heavily overloaded it would probably have blown apart. I calculate that 192 ohms will draw exactly 3 watts on a 24 volt supply.

So, if you'd like to have a try, buy a 3 watt 220 ohm resistor. If it gets pretty warm put your volt meter across it - then you'll know if you have a shorted regulator or something else. If it doesn't get warm you might just be lucky - use your voltmeter again to see what voltage is being dropped, and then by subtracting from the supply you'll know what is being fed to the board. Your regulator might be open circuit, in which case there will be no voltage across your 220 ohm resistor - in which case give up.

If you happen to have a board which runs on 12 volts instead of 5, all of the foregoing still applies - except, of course, your resistor only needs to drop about 10 volts and your dissipation will be much less.

You shouldn't need the motor or any controls connected to do this - just make sure you have a fuse in the battery lead - in case of accidents! It's less likely with a controller of the type you have (a brushed motor controller doesn't have FETS connected across the supply in pairs to give the three phases required by a brushless motor) but as has been said before, if you burn the house down or set fire to your crown jewels there's no warranty here - lithium batteries can produce a huge amount of power if you short them out.

Rog.

 

[aseb]

Thanks guys. I was on the point of trying a 300 ohm, my guess from what I think the pre-toasting colours may have been is 310 ohm so that's nearest standard value.
I've had a look at variable resistors and the price is getting to the area where it's not worth the risk, I might as well get a controller.
btw it is a 36V system.

So I might just try a couple of fixed value 3W resistors (< £1). Connecting in series and parallel will increase the choices, first thoughts 470, 330 and 68 ohms- connecting differently will give a range of 470 to 200 ohms (and beyond) with approx 65 ohm steps.
'If' it works there should be a suitable value in there, cost £1.65 at Maplin. I may be throwing all of that money away, but I'll risk it I think, like you, it's more hope than anything else but with the new motor/controller not too far away I think its my best bet.

Out of interest how much do you think the motor (700c rim, brushed, from x-byke, done under 2,000 miles) be worth, and does anyone know how much to post it to a buyer?