Could I just add a note of caution, I enquired on this forum about motor controller suitability for my Powabyke, I was thinking about buying a massively overrated controller on the premise (so I thought at the time) that the motor would only draw as much power as it needed and being under stressed it would more than likely last longer also, a good plan you might think?

This is the reply from D8VEH-

 

Just to re-inforce what NRG said: You can't use a controller that's rated higher than your battery and motor. It will try to draw too much current from the battery, which will cause it to cut-out. If you uprate the battery to be able to provide the current, then it'll try and push the maximum current that it's rated for through the motor, which will cause the motor to get hot and eventually burn. The three components need to be matched. Generally, 200/250w motors can take a maximum of 20amps if you don't use full power for too long. A 10aH lithium battery can only give 10 amps continuously and perhaps 20 amps for a very short time. Any more than 20 amps and the BMS will cut the power. SLA batteries can give a bit more for a short time and Lipos can give a lot more. 800w at v36v equals about 25 amps from the battery - just about possible from good 15aH SLAs, but you'd need at least 15aH lithium batteries.

 

The whole thread can be seen here-

 

http://www.pedelecs.co.uk/forum/electric-bicycles/10644-powabyke-motor-controller-suitability.html

 

I am not an expert on this subject and other than consult those who are far more knowledgable than myself I do not have a clue who is right or wrong. But, surely a 32 AMP controller, apart from the physical size and the problems that are likely to occur even mounting it, is capable of pushing out 1150 + Watts.

So hence my note of caution.

Edited May 17, 201213 yr by stemil

Correct!

I have replaced the motor controller on a Powabyke Euro, you really need to use a unit of the correct rating, ie 36v 250 watts, I used this one- ebay item 220875379732 which works great.

Unfortunately a std Powabyke throttle does not work with this unit, but ebay item 320795877868 does, the only downside being that the wires have to be extended as they are a bit on the short side, I used the original Powabyke throttle wire cut off long enough to rejoin if required. The wire colours on the new throttle match the colour on the new controller, which is handy.

Connecting everything up can be made much easier with ebay item 170711501780, 3.9mm bullet connectors as they go straight on the connectors fitted to the motor controller.

You will need to solder double wires from the motor and neg terminal to single connectors though, I also did not use the brake cut off switch as my bike did not have provision for it and I can't remember if you join the wires or not to get the controller to work, but it's one of the two and all fairly straightforward.

The total cost being about 20 quid.

I hope this saves you some grief.

 

Well chaps,, I am between a rock and a hard place and don't know which way to turn..To try the very generous offer from Frank or go for the Chinese controller and throttle. After reading the latest post's about using a higher rated controller I am scared stiff in case it burns anything out, I am just not in a position financially to replace origional parts or buy a new bike. I would hate being without my old Powabyke.....As far as the Chinese parts are concerned,,, the wiring up sound a little confusing,, particularly the part about soldering up double wires from the hub as there are only 2 wires coming out, could you possibly help me out to understand...I am happy to try anything to get me back on the road..

thank you

There is obviously a bit of confusion, and difference of opinion here. We need to agree on this , to help the guy get his bike back on the road. I have some background in practical and theoretical electronics, but I am open to correction, and I do not know everything. When we talk about a 35 amp controller, what exactly do we mean? Do we mean that the controller will shut itself down when we try to put more than 35 amps through it?.

As I understand it, a controller works by pulse width modulation. So it is basically a switch, which switches the motor on and off at a very rapid rate. At a low throttle setting, the switch spends more time off than on . As we open the throttle more, the "on" pulses get longer than the off ones. Finally, at full throttle, the motor is switched on at all times, and there are no off pulses.

So at full throttle, the controller plays little part in the circuit, apart from acting as a closed switch. So at this point, the current draw is determined only by the battery voltage , the motor resistance, the motor back EMF, and any resistance in the battery and wiring. So at this point we could replace the controller with a bit of wire, with no damage to the battery or motor except that the motor would run at full speed all the time .

So if I am right [and please tell me if I am wrong] You could fit a controller rated at 1000 amps and it would work without damaging motor or battery.

REMEMBER THAT IT IS IMPOSSIBLE TO DRAW MORE THAN 20 AMPS FROM THE BATTERY AS IT HAS A 20 AMP FUSE.

That is my opinion, but we desperately need other opinions.

One way out would be to do exactly what Stimil has done, as his bike seems to be working without any problems.

Hi you a right you can replace the controller with a on off switch it is a standard 36 volt brushed DC motor so on off full speed

 

Frank

Yes, like the brushless types speed control is achieved using PWM. At full speed = full battery voltage where the BEMF the motor produces = the applied voltage so the motor cant spin any faster. At full speed current draw is minimum. As Torque is proportional to current it is also minimum. Now assume you hit a hill, the motor slows but the voltage applied is still = battery voltage, to compensate the motor draws more current to increase torque so it can maintain speed...slow the motor more and even more torque is needed so current rises even higher.

 

This cant continue, you have to limit the current to some point as the motor is only designed to produce so much power, they are greedy little whotsits and if you don't limit what they consume they will take too much, overheat, burn out or fail mechanically...thats why you need to limit the current to the motor...brushed or brushless.

 

D.C. Motor Torque/Speed Curve Tutorial:::Understanding Motor Characteristics

 

http://lancet.mit.edu/motors/colorTS1.jpg

Edited May 18, 201213 yr by NRG

@NRG. Thanks for that explanation. This is more or less what I expected. So to return to practical matters. We do not know what the current limiter is set to in the original controller. Please tell me if you agree with the following three statements.

 

1. As the battery fuse is rated at 20 amps, the original controller will probably be 15 to 18 amps, so that working the motor hard will not blow the fuse, only an electrical fault will blow it.

 

2. If we fit a controller rated as say 30 amps, we will have no problem unless we work the motor really hard . If we do, the fuse will blow.

 

 

3.So basically what I am saying is that the ideal controller for this bike would be rated at 36 volts, 15 to 18 amps , which is equal to 440 watts.

 

Look on Ebay for 36v 250-350 W Speed Controller Box Electric Bike Scooter. Seller is novaproductsuk.

Same seller has also a throttle , check all dimensions. Controller is limited to 18 amps which is near enough.Wiring up looks straightforward.

Edited May 18, 201213 yr by neptune

Hi Russell Hear is the links for the parts Neptune recomended

 

36v 250-350W Speed Controller Box Electric Bike Scooter | eBay

 

 

eBay - The UK's Online Marketplace

 

Frank

Hi Russell Hear is the links for the parts Neptune recomended

 

36v 250-350W Speed Controller Box Electric Bike Scooter | eBay

 

 

eBay - The UK's Online Marketplace

 

Frank

 

Well, what can I say,,,I am flabbergasted that you lovely people I have never met could be so very helpful..This forum is a wonderful example of why the older generation should embrace the Internet, they would soon recognise as I have that although many things that go on in our society make us all nervous and sometimes uncomfortable, there are always hundreds of good people out there who are prepared to give their own time up simply to help people...Thank you all.

I am going to go for the controller and throttle that neptune recommends but would feel less nervous if I could possibly post another question if I have problems wiring it up.

If you feel you have all helped enough I will understand,,,,I will let you know how I get on,,,,regards Russell

Well, what can I say,,,I am flabbergasted that you lovely people I have never met could be so very helpful..This forum is a wonderful example of why the older generation should embrace the Internet, they would soon recognise as I have that although many things that go on in our society make us all nervous and sometimes uncomfortable, there are always hundreds of good people out there who are prepared to give their own time up simply to help people...Thank you all.

I am going to go for the controller and throttle that neptune recommends but would feel less nervous if I could possibly post another question if I have problems wiring it up.

If you feel you have all helped enough I will understand,,,,I will let you know how I get on,,,,regards Russell

 

Just looking at the picture of the controller,,,the original controller doesn't have any plugs on it just plug in sockets, I am a little confused or probably just stupid,,,,

Hi Russell. This is what I meant when I said in an earlier post that a sustitute controller may not be "plug and play". Bear in mind that I although I have worked in electronics, I have never actually seen one of these controllers, and although I run a Euro, I have had no cause to get the controller out. If you look at the picture of the controller, it has connectors on the ends of the wires. It is hard to tell from the photo, but some of these connectors may be female, or sockets. Equally, they may not be. In that case you will have to remove at least some of these connectors, and replace them with connectors that are compatible with the connectors on the wiring of the bike. If such can not be found , you will have to change the connectors on the bike wiring as well. Note that this controller does not have a pedalec option. Nor does it have a connection for the motion sensor fitted to the rear wheel of your bike, if it is a pre 2002 model . The only down side of this, is that if you switch on the ignition, the bike will pull away from a standstill as soon as you open the throttle. This is bad for the motor and battery, so the way to ride it will be to pedal up to about 4MPH before opening the throttle.

Some of the wires on the controller can remain unused, like the brake cutouts, and the charger wires because you already have a charge socket on your battery . The wires you will have to connect are as follows.

2 motor wires.

2 battery wires.

3 throttle wires.

2 Ignition switch wires.

and if required, 2 wires for the battery level indicator .

So you are looking at changing some connectors and doing some soldering. There are several types of connector that will serve, including automotive bullet connectors, and automotive blade connectors. It is important that you understand what is involved before you commit yourself. It is a shame you don`t live nearer to me. Do not pull any wire off your old controller without carefully making a diagram. If you decide to go ahead, I will give you my phone number via private message . Remove battery from bike before doing any work at all .

..This forum is a wonderful example of why the older generation should embrace the Internet ...regards Russell

 

Hi Russell. Pleased you have found those lovely people on this Forum to help. Sorry that I've not been sufficiently knowledgeable ... or old enough ... to contribute ... I'm only 71 (or is it 72?)

 

Don

Hi Russell. This is what I meant when I said in an earlier post that a sustitute controller may not be "plug and play". Bear in mind that I although I have worked in electronics, I have never actually seen one of these controllers, and although I run a Euro, I have had no cause to get the controller out. If you look at the picture of the controller, it has connectors on the ends of the wires. It is hard to tell from the photo, but some of these connectors may be female, or sockets. Equally, they may not be. In that case you will have to remove at least some of these connectors, and replace them with connectors that are compatible with the connectors on the wiring of the bike. If such can not be found , you will have to change the connectors on the bike wiring as well. Note that this controller does not have a pedalec option. Nor does it have a connection for the motion sensor fitted to the rear wheel of your bike, if it is a pre 2002 model . The only down side of this, is that if you switch on the ignition, the bike will pull away from a standstill as soon as you open the throttle. This is bad for the motor and battery, so the way to ride it will be to pedal up to about 4MPH before opening the throttle.

Some of the wires on the controller can remain unused, like the brake cutouts, and the charger wires because you already have a charge socket on your battery . The wires you will have to connect are as follows.

2 motor wires.

2 battery wires.

3 throttle wires.

2 Ignition switch wires.

and if required, 2 wires for the battery level indicator .

So you are looking at changing some connectors and doing some soldering. There are several types of connector that will serve, including automotive bullet connectors, and automotive blade connectors. It is important that you understand what is involved before you commit yourself. It is a shame you don`t live nearer to me. Do not pull any wire off your old controller without carefully making a diagram. If you decide to go ahead, I will give you my phone number via private message . Remove battery from bike before doing any work at all .

 

Thank you for the guidance,,,it doesn't sound too bad, I will order the parts and go for it, first I will take out the controller and try to familiarise myself with what each socket is for and the colour of the wires going into each socket from the bike,, I will also take pictures of each step of the way to refresh my memory,,,fingers crossed,,,I dont know whereabouts in the country you are but if you were nearby I would have the greatest pleasure in treating you to a pint. I promise to let you know how I get on

 

regards Russell

Thank you for the guidance,,,it doesn't sound too bad, I will order the parts and go for it, first I will take out the controller and try to familiarise myself with what each socket is for and the colour of the wires going into each socket from the bike,, I will also take pictures of each step of the way to refresh my memory,,,fingers crossed,,,I dont know whereabouts in the country you are but if you were nearby I would have the greatest pleasure in treating you to a pint. I promise to let you know how I get on

 

regards Russell

 

I have just had a look on the Powabyke web site and found the wiring connections they read

7 pin power

pedal/motion sensor 3 pin

ignition 3 pin

throttle 3 pin will this cause me problems with the replacement, I promise I wont bother you again (at least not tonight)

As far as the Chinese parts are concerned,,, the wiring up sound a little confusing,, particularly the part about soldering up double wires from the hub as there are only 2 wires coming out, could you possibly help me out to understand...I am happy to try anything to get me back on the road..

thank you

 

Hi Russell, The Motor cable doubles up above the connector located on the left fork, I do not have the bike to hand at the moment but going from memory red and blue = positive, yellow and green = negative.

Roughly where are you located?

Good luck.

There's quite a nice panel on ebay at the moment BTW, I don't know whether or not it is suitable for your model of Powabyke but would definately smarten things up-

 

Item 170840866732

@Stemil. I am glad to see you on this thread, as your information is based on practical experience.

@Russel. Please do not worry about how many questions you need to ask us . That is the whole purpose of this forum. I would rather answer one thousand questions than see you get it wrong. Do not worry about the "double wiring"to the hub at this stage.

Vital questions for you.

Have you checked the dimensions of the new controller to make sure it will fit the available space.

Can you solder, and do you have a soldering iron?

Do you have a multimeter, and do you know how to use it?

 

One area where you might struggle is wiring up the ignition switch . We can talk you through it , but you probably need a multimeter for the job. I believe you are in Leicester, I am in Boston , Lincs.I am going out for a bit, but back later.

Edited May 19, 201213 yr by neptune

Hi Russell, The Motor cable doubles up above the connector located on the left fork, I do not have the bike to hand at the moment but going from memory red and blue = positive, yellow and green = negative.

Roughly where are you located?

Good luck.

 

I have just had a look on the Powabyke web site and found the wiring connections they read

7 pin power

pedal/motion sensor 3 pin

ignition 3 pin

throttle 3 pin will this cause me problems with the replacement, I promise I wont bother you again (at least not tonight)

There's quite a nice panel on ebay at the moment BTW, I don't know whether or not it is suitable for your model of Powabyke but would definately smarten things up-

 

Item 170840866732

 

At long last someone has responded to a gap in the market for aftermarket extras......I agree , it is a very useful smart panel, unfortunately the auction has ended and is not relisted but I have emailed the seller in the hope that they are available,, it is for my model and would as you say smarten it up.If I cant get one I will think about cutting one out myself,,I have that much junk in my garage I'm sure to find something.......thanks for letting me know,,,did you see my post about the Powabyke website and the controller connections?/

@NRG. Thanks for that explanation. This is more or less what I expected. So to return to practical matters. We do not know what the current limiter is set to in the original controller. Please tell me if you agree with the following three statements.

 

1. As the battery fuse is rated at 20 amps, the original controller will probably be 15 to 18 amps, so that working the motor hard will not blow the fuse, only an electrical fault will blow it.

 

2. If we fit a controller rated as say 30 amps, we will have no problem unless we work the motor really hard . If we do, the fuse will blow.

 

 

3.So basically what I am saying is that the ideal controller for this bike would be rated at 36 volts, 15 to 18 amps , which is equal to 440 watts.

 

Look on Ebay for 36v 250-350 W Speed Controller Box Electric Bike Scooter. Seller is novaproductsuk.

Same seller has also a throttle , check all dimensions. Controller is limited to 18 amps which is near enough.Wiring up looks straightforward.

 

1. Yes, could well be.

2. Not really, you should rate the controller to fit the battery and motor rating as per the quote from d8veh, we dont want to use the fuse as a current limiter!

3. It would seem so...

@NRG. Thanks for kindly commenting on my statements. I have learned some thing myself here about the need for current limiting.

@Russell. If you decide to buy the controller , buy the throttle from the same supplier , you will get a compatible throttle, which will plug straight into the new controller, and save on postage . Do not order anything without checking dimensions, including handlebar size.If you decide to go for it I will post a step by step guide to wiring up.

 

Important question. is your bike the model with the motor in the front wheel and 5 speed gears and the motion sensor on the back wheel, left side.

 

If it is, I will strip out the controller from my bike to have a look what goes where to help me to help you .I will not do this untill you let me know that you are going ahead with the project .

 

@Stimil. I have not had a look at the bike yet, but trying to grasp the double wiring thing . My understanding is as follows. The cable that leaves the hub is a 2 wire cable. At the plug and socket near the hub, it becomes a 4 wire cable, so you have two wires in parallel for the positive, and two in parallel for the negative. The other end of this four wire cable terminates on 4 separate pins on the 7 way "power plug" that plugs onto the controller. When connecting to a new controller, the 4 wires are connected to just 2 wires coming out of the controller. So at the controller, the red and blue wires from the motor are both connected to the controller positive motor terminal. The green and yellow wires from the motor are both connected to the cotrollers negative motor wire . Is my understanding correct?

Edited May 19, 201213 yr by neptune

Hi Russell. This is what I meant when I said in an earlier post that a sustitute controller may not be "plug and play". Bear in mind that I although I have worked in electronics, I have never actually seen one of these controllers, and although I run a Euro, I have had no cause to get the controller out. If you look at the picture of the controller, it has connectors on the ends of the wires. It is hard to tell from the photo, but some of these connectors may be female, or sockets. Equally, they may not be. In that case you will have to remove at least some of these connectors, and replace them with connectors that are compatible with the connectors on the wiring of the bike. If such can not be found , you will have to change the connectors on the bike wiring as well. Note that this controller does not have a pedalec option. Nor does it have a connection for the motion sensor fitted to the rear wheel of your bike, if it is a pre 2002 model . The only down side of this, is that if you switch on the ignition, the bike will pull away from a standstill as soon as you open the throttle. This is bad for the motor and battery, so the way to ride it will be to pedal up to about 4MPH before opening the throttle.

Some of the wires on the controller can remain unused, like the brake cutouts, and the charger wires because you already have a charge socket on your battery . The wires you will have to connect are as follows.

2 motor wires.

2 battery wires.

3 throttle wires.

2 Ignition switch wires.

and if required, 2 wires for the battery level indicator .

So you are looking at changing some connectors and doing some soldering. There are several types of connector that will serve, including automotive bullet connectors, and automotive blade connectors. It is important that you understand what is involved before you commit yourself. It is a shame you don`t live nearer to me. Do not pull any wire off your old controller without carefully making a diagram. If you decide to go ahead, I will give you my phone number via private message . Remove battery from bike before doing any work at all .

 

Hello again,,,I have taken a look at the faulty controller so that I can understand the one listed on Ebay a little better,,,and after reading your guidance above on what the new controller can and cannot do.

I have just remembered that when I bought the bike years ago second hand there was no sensor on the pedal crank. The chap I bought it off told me that he had been fitted with a new controller previously and also had some kind of link cable that bypassed the sensor which meant I could just get on the bike and turn throttle which I have done since getting the back some years ago until of course I messed everything up when tidying the wiring from the hub up.So that fact that the new controller doesn't have a sensor or movement option doesn't matter...When I can clear my brain a little (I get the old man syndrom when reading all of the technical stuff) I will buy whatever you suggest is best and get on with it,,Summer is on its way...My Powabyke is the 5 gear with pedal sensor and external sockets on the controller,, I understand the old type sensor had the sockets on the inside of the controller case which meant you had to get inside the controller to do anything... I have just seen an original one listed on Ebay at £50,, I dont know if this will be any help to you,,,,,,,,thanks again.

@NRG. Thanks for kindly commenting on my statements. I have learned some thing myself here about the need for current limiting.

@Russell. If you decide to buy the controller , buy the throttle from the same supplier , you will get a compatible throttle, which will plug straight into the new controller, and save on postage . Do not order anything without checking dimensions, including handlebar size.If you decide to go for it I will post a step by step guide to wiring up.

 

 

 

Important question. is your bike the model with the motor in the front wheel and 5 speed gears and the motion sensor on the back wheel, left side.

 

If it is, I will strip out the controller from my bike to have a look what goes where to help me to help you .I will not do this untill you let me know that you are going ahead with the project .

 

@Stimil. I have not had a look at the bike yet, but trying to grasp the double wiring thing . My understanding is as follows. The cable that leaves the hub is a 2 wire cable. At the plug and socket near the hub, it becomes a 4 wire cable, so you have two wires in parallel for the positive, and two in parallel for the negative. The other end of this four wire cable terminates on 4 separate pins on the 7 way "power plug" that plugs onto the controller. When connecting to a new controller, the 4 wires are connected to just 2 wires coming out of the controller. So at the controller, the red and blue wires from the motor are both connected to the controller positive motor terminal. The green and yellow wires from the motor are both connected to the cotrollers negative motor wire . Is my understanding correct?

 

Sorry I missed the Ebay listing number for the controller I understand this is an original Powabyke part.. 180878576114

OK Russell. I just took a look at that new type controller on Ebay . There is some info on the Powabyke website about that one . My bike appears to still have the original controller with the motion sensor option, so looking at mine will not help me to help you. If you can, have a look at the controller fitted to your bike. If it is the same as the one on Ebay, it will make life easier , as it will plug straight in [Plug-and-play].

 

HOWEVER, you will still have to replace the throttle. If you look on the Powabyke website there is a fault finding guide for your bike. It warns that with the fault you have, you MUST replace BOTH throttle and controller, or you will damage the new controller.

 

 

If your throttle is a three wire throttle, you may get away with a chinese one. It is you who must make any final decisions, as its your money. I will give you the best advice i can, of course, but I can not be held responsible if the manure hits the fan!

 

If your existing controller is identical to the one on Ebay , any bypass cable for the sensor will plug straight into the new one. I am feeling tired tonight so I am going to bed, but will be around tomorrow sometime.

Edited May 19, 201213 yr by neptune

Hi All, yes neptune your understanding of the motor wiring is correct.

Russell, we have two Powabyke euros, when the controller burnt out on the blue one I ordered two sets of controllers and throttles, so if you like I will send you the the second unused set which you can have at cost + postage, about 20 quid all in, please let me know and I'll get it in the post on Monday and you can send a cheque off or pay by Paypal or something.

I do not have access to the blue bike at present but going from memory the wiring on the new controller is like so-

 

Positive from battery double wire to red new controller wire

 

Negative from ignition switch to new controller black wire (I think from memory it is a switched negative, if not simply swap the wires over to the correct polarity)

 

Connect the red and blue wires from the motor to the blue wire on the new controller

 

Connect the green and yellow wires from the motor to the white wire on the new controller

 

Cut the cable on your old throttle off long enough to sufficiently lengthen the wire on your new throttle,

join this by soldering to your new throttle and shrink tube over each seperate wire to insulate, the colours match on the new throttle to the new controller, ie green/black/red but not on the cable you are using from your old throttle, so make a note of what goes where.

 

Join the green/black/red throttle wires on the new controller to your newly extended throttle wire by the same method as above.

 

The black and yellow wires on the new controller are for the brake cut off switch, not used on this bike and sorry I can't remember if they are connected or not to get the controller working, one of the two though.

 

Finally, disconnect the two black wires fitted with the male and female connectors, this is a speed limiter feature on this controller apparently.

 

Really to make a neat and secure job you will need to order some of those 3.9mm bullet connectors from ebay.

I will send you some shrink tubing as well if you want the controller as I have loads knocking around.

 

I have tried to make this as unconfusing as possible hence the constant reference to "new controller" etc, and also so that you can decide if this is a job for you or not.

 

 

[ATTACH]3658.vB[/ATTACH]

Edited May 19, 201213 yr by stemil