Help please( reversed polarity damage)

[Floatything]

Help! I've managed to put reverse polarity through my powabyke. It's a 2000 folding bike. Having opened up the controller, there's clear damage to a resistor in position R19. It's so burnt that I can't read the colour codes. Do you know it's value so I can start by replacing that? Thanks.

 

[Nealh]

I see the Cap at C12 has been removed also just visible in you pic, I assume the top exploded as well ?
The resistor you may have to take punt on it and look at any near the other Caps like C11, If the Cap is of the same value then the adjacent resistor/s may be of the same value as your blown one.
Having replaced any suspect component, damage elsewhere may not be visible such as the mosfets or any small diodes.

 

[Floatything]

I see the Cap at C12 has been removed also just visible in you pic, I assume the top exploded as well ?
The resistor you may have to take punt on it and look at any near the other Caps like C11, If the Cap is of the same value then the adjacent resistor/s may be of the same value as your blown one.
Having replaced any suspect component, damage elsewhere may not be visible such as the mosfets or any small diodes.

Thanks. I removed & tested the C12 capacitor & it seems ok. The blown resistor at R19 is bigger then everything else on the board so I'm not sure. You're probably right that something else is damaged but I'll cross that bridge later...once I've worked out R19's value.

 

[Andy-Mat]

First, I must compliment you on your work up to now, always good to "have go".
But sadly, I have to agree with another poster here, that its unlikely that the MOSFETs will have survived....and diodes, some polarised caps will also taken a "hit!". Even if not YET defective, they may be "weakened" and fail a few weeks later....
So before you invest in much time, may I suggest that you simply replace the controller with an identical one, if possible. Sorry to be negative....
Simply replace with a new controller, one with an LCD from say ebay....They cost from about 30 UK pounds upwards.
Maybe someone here has done that already and can give some good advice?
But before you do that, also get the motor Hall effect sensors checked out, as they can also get damaged, far less likely, but still possible, as they are a voltage sensitive device.
This video may help further in understanding them:-

What is a hall sensor and why do electric bike motors need them? | Panda eBikes

www.pandaebikes.com

The next video shows testing and how to replace them, but you should be able to test them where they connect to the controller unit, its often a 6 wire white plastic connector block. Hopefully, there is enough residual magnetism in the rotor to switch them, but I have never tested that myself in that way, only with an external magnet! In this video he talks about "welding", he means "soldering"....

Remember:-
Some 3 phase motors do not have them anyway, because:-
Some controllers do not need them!
And some motors are brushed and do not have them either....though seldom brushed IMHO on modern e-bikes.
Most motors today are technically basically a 3 phase AC motor, but designed for switched 3 phase low voltage DC....
Just some thoughts, but some others here will have already done what you need to do, listen to them carefully.
regards
Andy

 

[vfr400]

First, I must compliment you on your work up to now, always good to "have go".
But sadly, I have to agree with another poster here, that its unlikely that the MOSFETs will have survived....and diodes, some polarised caps will also taken a "hit!". Even if not YET defective, they may be "weakened" and fail a few weeks later....
So before you invest in much time, may I suggest that you simply replace the controller with an identical one, if possible. Sorry to be negative....
Simply replace with a new controller, one with an LCD from say ebay....They cost from about 30 UK pounds upwards.
Maybe someone here has done that already and can give some good advice?
But before you do that, also get the motor Hall effect sensors checked out, as they can also get damaged, far less likely, but still possible, as they are a voltage sensitive device.
This video may help further in understanding them:-

What is a hall sensor and why do electric bike motors need them? | Panda eBikes

www.pandaebikes.com

The next video shows testing and how to replace them, but you should be able to test them where they connect to the controller unit, its often a 6 wire white plastic connector block. Hopefully, there is enough residual magnetism in the rotor to switch them, but I have never tested that myself in that way, only with an external magnet! In this video he talks about "welding", he means "soldering"....

Remember:-
Some 3 phase motors do not have them anyway, because:-
Some controllers do not need them!
And some motors are brushed and do not have them either....though seldom brushed IMHO on modern e-bikes.
Most motors today are technically basically a 3 phase AC motor, but designed for switched 3 phase low voltage DC....
Just some thoughts, but some others here will have already done what you need to do, listen to them carefully.
regards
Andy

It's a brushed motor!

 

[Andy-Mat]

It's a brushed motor!

Thats really good, no Hall effect sensors!
One problem solved!
I have seen brushed motor e-bike controllers on ebay, but far less often...sadly!
Something like this maybe?

500W 24/36/48V E-Bike Motor Brushed Motor Controller Roller Dreirad Set DE | eBay

Finden Sie Top-Angebote für 500W 24/36/48V E-Bike Motor Brushed Motor Controller Roller Dreirad Set DE bei eBay. Kostenlose Lieferung für viele Artikel!

www.ebay.de

Best of luck.
Andy

 

[vfr400]

The one in the photo in this thread looks like brown, black,black, gold, brown, which would be 10 Ohms. Maybe my monitor doesn't show true colours. what do others think.

Power/Torque increase on a Powabyke Euro 6 speed?

Hi guys, I have had a defunct euro 6 speed in the shed for about 6 months waiting for a diagnosis and repair but before I started on that I was hoping for some advice from the more knowledgable members about upgrading. The root of the problem is that my daily ride to work...

www.pedelecs.co.uk

Also, it's for a Euro, which is 36V. On other controllers, that resistor is used to cut the voltage down for the 12V regulator. Powarbyke controllers always seem to be a bit different.

 

[vfr400]

You could chuck all the electrics and use a standard controller like this one:

Electric Brushed Motor DC Controller 24V 36V 250W Speed Controller with PAS Sensor Port For Electric Bicycle Scooter Accessories - AliExpress 18

Smarter Shopping, Better Living! Aliexpress.com

www.aliexpress.com

It'll work with a standard throttle and standard pedal sensor, so you'd most likely have to replace them too, especially as Powabyke throttles normally work backwards compared with normal ones, i.e. with a standard controller, opening the throttle would turn down the power.

 

[Deleted member 25121]

The one in the photo in this thread looks like brown, black,black, gold, brown, which would be 10 Ohms. Maybe my monitor doesn't show true colours. what do others think.

Yep, I think that's right 10 ohm, 1% using the 5 band code. Probably 1 Watt judging from its size relative to other parts.

I'd be tempted to try 100 ohm first to see if anything starts to work, if not then 47 ohm and then if not, 10 ohm. After all, there's nothing to lose...

 

[Floatything]

Thanks everybody! I'll give it a shot with a 10 ohm then if nothing happens I'll send it of for a refurb. A chap named Berni was suggested by Powabyke.