Hi, also in need of controller advice!

Pendelton Somerby, bought secondhand so no idea how the battery was looked after, came fully charged but had lost the charger,

Test ride went fine, discovered that when stopping and turning back on again we get nothing battery pack shows full charge, but lights on display show 1 battery and flashing red led for the low mode on the 790 controller, ( Abnormal current apparently, no idea what that means in reality)

However if left for 24 hours, no charging it will work fine, then the symptoms repeat themselves?

Any ideas, I've taken the controller out and connections look fine but I'd like to replace /upgrade if possible, not looking to go faster! Cant find an exact match to the controller on line its an Santroll 36v mac current 15a rated 7A low voltage 31v, happy to replace that the display brakes and cadence

Abnormal current usually means a controllee mosfet fault and it is likely a thermal cut out, once it cools it swtiches again to work until the next cut out.

 

There are cheap similar controller kits that use the the carppy speed control but I woul dadvise spending few more pounds and buy a KT controller kit for about £80 - £100.

 

Where to buy ebay /amazon quite dear if you are willing to wait 1- 3weeks then buying form china is cheaper either Aliexpress or topbike kit.

Much appreciated, any guidance on the kit? I'll try topbike kit

From the topbike kit store on AliExp.

eBike 36V250W Motor Controller KT Controller Kit 24V/36V15A+Throttle+KT-D12L PAS+Brake+KT LCD Display/ Ebike Motor Controller - AliExpress

 

If you have the space for the controller (slightly larger ) I would opt for the 9 mosfet 22a controller for better heat control.

Ebike KT Controller 36V/48V500W Motor Controller 22A Ebike Sine Wave Controller +KT LCD3/LCD4/LCD5/LCD8H/LCD8S/LCD9 Display - AliExpress

 

Select the display that suits as one can choose various form KT that are all compatible with their controllers. LCD4 is neat and small but fiddly , LCD3 has always been my go to LCD though one can also look at the others like LCD5 , LCD8 or 10 .

There is a comprehensive thread on changing the Somerby controller here:-

 

Pendleton eSomerby Controller Upgrade | Pedelecs - Electric Bike Community

There are two types of wiring both plug and play, either waterproof with moulded plugs which are not easy to fault find (without the know how) or the square SM type plug where one can fault find issues easily .

 

The KT uses current as the power control which gives far superior relaxing ride (from rider input) and controlfrom the rider , decide the best power level from the five PAS levels available to suit the road /riding conditions.

Thanks again ordered as per thread plus bits

There are two types of wiring both plug and play, either waterproof with moulded plugs which are not easy to fault find (without the know how) or the square SM type plug where one can fault find issues easily .

 

The KT uses current as the power control which gives far superior relaxing ride (from rider input) and controlfrom the rider , decide the best power level from the five PAS levels available to suit the road /riding conditions.

HELP! Just fitted everything as per Pendelton thread and no power at all, LCD is not turning on and getting no power form the controller

If you have no power then the battery is the issue.

Is is charged ?

Does it output voltage ?

Have you checked the out put voltage ?

I think I may have connected the battery the wrong way around when I took the casing apart to change the controller , possibly blown the fuse in the Yose battery as a result, it’s an external serviceable fuse.

I’ve just ordered a multimeter how can I test the prongs for positive and negative will I get the same reading if I connect bot ways round?

I think I may have connected the battery the wrong way around when I took the casing apart to change the controller , possibly blown the fuse in the Yose battery as a result, it’s an external serviceable fuse.

I’ve just ordered a multimeter how can I test the prongs for positive and negative will I get the same reading if I connect bot ways round?

If you connect the controller the wrong way round, it will kill the controller instantly. Your only hope is that there's a fuse in the battery, but I'm not sure that it would save it even if there is one.

 

I would open up the controller to see if the shunt is still intact and what the state of the main capacitor is, or whether there's any other damage in there.

Yes wrong polarity will kill the controller, you may find the the in rush capacitor has exploded (it is possible you heard a pop or noticed a strange smell at the time).

 

Use the two outer contacts on the discharge outlet (one each side), it matter not which way the probes go. The only thing that occurs when the probes are reversed is one will see a minus sign before the reading.

Thanks guys, I guess I got lucky, it just blew a fuse in the Yosa battery, it was accessible externally once removed from the battery tray/holder so no big deal.

I used a multimeter to get it right second time around, then discovered the battery actually showed + &- above the prongs, but was minuscule!

 

SO all good, works really smoothly, big improvement and actually goes around 3mph faster which is more than enough for it's intended use.

 

Just a thank you to all those that have posted responses and obviously to Bikes4two for the original Pendleton post.