D8veh

If the motor has the standard 9-pin connector, the battery connects to the controller with only two wires and you have a cadence pedal sensor (not torque sensor), you can use any controller you want. If you show what you have with all the connectors spread out so that we can se them, we'd be able to give more specific advice. Why do you want to change the controller? If you think it's broken, how did you ome to that concluion?

At a recent landlords meeting, we had a presentation from the council, and they brought along a spokesperson from an energy poverty charity to give a talk about heatpumps and energy poverty. They both pleaded with us not to install any heatpumps in our rented properties because they were multiple times more expensive to heat a house or flat compared with a gas boiler. They said they're having a massive increase in calls from people not able to heat their properties, and it's nearly always because a heatpump had been installed. I'm not exagerrating what they said. I have no experience of heatpumps myself, other than my fridge and the one my sister uses to cool her house in summer, which uses quite a lot of power - about 2kw IIRC. The unit you linked to is 3.5kw!

Do you ride with two fingers on the break, like a motorcyclist does? The small pressure can be enough to cut the motor. Try disconnecting the brake switches to see if the problem goes away. The only other thing I can think of is that the battery is insufficient. Do you have a decent battery? What is it and what current do you have your controller set to?

Does your bike have lights, and are they operated by the LCD? That's normally what the red 2-pin connector is for. As long as you have the standard 5-pin connector on the replacement, it should work, but you'd have to use battery lights or wire them to the battery through a separate switch and fuse; however, there can be software differences in the LCD, which means that they don't work with all controllers. Your controller is integrated into the battery receiver and wired directly to the connector. You can get a better controller and LCD as a pair for about £100, but you'd have do some soldering to the wires.

What do you mean by "set to off"?

If the motor has the standard 9-pin connector, you can use any controller and battery. If it doesn't, it's pretty easy to wire in a second battery if you need more range. The original controller needs to do handshaking with the present battery before it will work, but if you wire in the extender battery to the two main power wires using one of those Aliexpress parallel battery devices, the extension battery won't need to communicate, because the comms will be done by the main battery.

Yes, there are lots of them. I've even fitted a few myself. Why do you ask?

Can I ask who the professional installer was?

That guy tested at 120v and 15A. Your 48v battery charges at 2A to 54v, which will be fine. In real terms, you'll probably be able to convert about 80% of the nominal charge from your 36v batteries, so you're going to have to make sure you bring enough. Using that device, you could use a 36v battery as a range extendender by connecting it to the charge port of your 48v battery while riding. A better solution would be to use a KT dual voltage controller, then you can useboth your 36v and 48v batteries directly without a converter. I tested that it works on my folding bike.

900W 15A CC CV Adjustable LCD Digital Power Supply Module DC 9-60V to DC 10-120V Step Up Boost Converter Voltage Regulator - AliExpress 502

It's a standard Chinese ebike with all the normal standard interchangeable/upgradeable components. I would have said the price is about right, though £300 would be more like it for me, considering that you you can buy new ebikes for the same price from halfords: https://www.halfords.com/bikes/electric-bikes/assist-step-thru-electric-hybrid-bike-425699.html?cm_mmc=Google+PLA-_-Cycling%3EBikes%3EAll+Electric+Bikes-_-Cycling%3EBikes%3EAll+Electric+Bikes-_-425699&srsltid=AfmBOopZkHd54CLEJ_eXQVqiQ3cJNCtqeu0Q7SL4nPaRCUYVdAZEqPzV1L0

No, it's unlikely that there's anything wrong with the LCD if the other functions are working. The LCD works completely independently from the rest of the bike. It communicates with the controller via two data wires to share information about speed, power and settings. If the communication was interrupted, the speed wouldn't show, but then you wouldn't be able to change pedal assist level either. The only thing that go wrong is when you mess with the settings and change the setting for the number of magnets in the speed sensor, which will cause both the LCD and controller to wrongly interpret the speed too low or too high. Your first step should be to check that the motor connector is in ALL THE WAY TO THE MARKED LINE, not just in tight, then check that the cable isn’t nicked, especially where it exits the axle. It's quite common for the magnet on the inside of the motor side-plate to come unstuck, since it's only glued on. You test that by measuring the voltage on the white wire while you rotate the rear wheel with the bike powered and switched on. It should pulse once or 6 times with each rotation, depending on how many magners you have. The pulse can be from zero to 5v or from 5v down to zero, depending on how your controller does it.

You need to test the speed sensor signal. I can't remmember if it's a separate wheel sensor or in the motor. if it's in the motor, it's the white wire in the cable, which should pulse onece or 6 times with each wheel rotation. If it's a wheel magnet type, it could be just knocked crooked or out of line. The motor one won't work if the motor connector isn't pushed in far enough, if the magnet detatches inside the hub, if the cable gets damaged or sometimes water in the hub could cause it.

I'm not sure what or how you measured. Your description is vague and unfocused, so you probably did it wrong. Here's how you test, but first you need to identify the cables and wires by following them from their source. 0. Before anything, check that the motor connector is in ALL THE WAY TO THE LINE, NOT JUST IN TIGHT: 1. Measure the voltage at controller's battery connector. Obviously should be battery voltage. 36v - 42v for a 36v battery would be an acceptable range, but if you've fully charged the battery and it's less than 41v, it needs some sorting. 2. Measure the voltage on the 5v rail. You can measure that between any ground (black) and any of the reds going to throttle, PAS or motor halls. It should be around 5v. 3. Check throttle signal wire voltage on it's connector while connected. it's the wire that's not red or black on the throttle connector. Should change from about 1v to 4v when you twist the throttle. If there's more than one wire, your meter will find it. It's the one that's between 1v and 4v, assuming that it works. 4. Check that the pedal assist sensor is pulsing. Measure the PAS signal wire while turning the pedals slowly. Should pulse 5v on and off every time a magnet passes the sensor. The signal wire is the one that's not red or black. 5. Check the motor hall signal wires (blue green and yellow) on the motor connector at the controller. They should each pulse with 5v going on and off as you rotate the wheel BACKWARDS. 6. Mosfet test. Disconnect the motor cable and battery from the controller. Measure the resistance (200k scale) between the red battery connection and each of the three phase wire connections, then repeat with the black battery wire. Each set of 3 readings should be the same as each other and in the range 7K -24K. Though can be higher as long as they're all the same. Due to the capacitor across the battery wire, you can get a constantantly changing measurement while it charges. In that case, try swapping your probes round. Even though can be a moving result, the only important thing is that all three move in a similar way. If your bike passes all those tests, it should work, so then you can look at any settings or other logical causes, like stuck brake switches.

I always recommend that you don't plug in any lights to any socket on the controller, especially a switched one. It's too easy to blow any switching transistor, which would lead to problems. It's just as easy to wire any lights directly to the battery wires. All you need is a switch and a fuse. That's very safe, as the circuit is protected by both the fuse and the BMS in the battery.

I built this one from a Whyte road bike that I paid about £150 for in 2017 with a 1.5kg Xiongda motor and I built my own 1kg battery. I later changed it to a rear Xiongda cassette motor with a standard 1.2kg bottle battery from Aliexpress. The whole kit was less than £250: Uploading Attachment...

That's what I'd do if I wanted a lightweight ebike. You can get a nice donor for about £250, add your own lightweight electrical stuff for less than £400. Then you have a really nice ebike that you're in control of re spares etc. No need to worry about invalidating warranties or anything like that, and you can buy multiple batteries of any size for whatever length journey you want, and each one would cost less than £200. I have a little folding bike that can run an 8Ah 24v battery or 10Ah 36v one - completely interchangeable, and a nice KT control system.

Any kit with a cassette motor will work. The only thing you need to look out for is that the motor is marked 250w. All motors are 36 hole, so get a normal rim and disc brake if yoy can, which will be much better than any rim brake. Woosh in UK sell a MXUS XF08C kit for between £530 and £660, which would be OK, but if you want a perfect kit, tuned to your needs, it might be better to buy individual components for a total of about.£600. You'd need to tell us about what you're aiming at if you want specific advice.

You can use any battery you like as a range extender and you don't need to buy any special system or phone app. All you have to do is splice two wires to the two battery power wires somewhere between the main battery and the motor. If you do as simple as that, both batteries need to be fully-charged when you connect the extender. They will both go down in voltage together until the Bosch battery switches off when empty. Next up from that is one of those Aliexpress/Ebay parallel battery diode arrangements for about £20. With one of those, you can connect the extender battery at any state of charge. Whichever battery is highest will go down until they're the same voltage, then they'll go down together. It will work as long as the Bosch battery has enough charge to switch on because the Bosch battery is needed to do the hand-shaking protocols. The extender doesn't need comms to work in parallel, even if it's the one providing all the power.

You need to read what you wrote again. How can the low cells catch up during charging, when the same current passes through all of them? The low cells never catch UP. It's the high cells that bleed DOWN after the charge stops. You're right that there should never be any cells above the cut-off voltage unless something has gone wrong.

I've ordered one, though I'm not sure when delivery will come. I paid about £900. I'll let you know if it works. I'll wear baggy trousers and hum so nobody knows I've got it.

Did he indicate the part numbers or batch numbers? I can't read it because I don't want the cookies.

They all look fine. If you can hang on a few weeks until the weather is a bit warmer, I'll come to you with a couple of other controllers to try. I'll contact you nearer the time to make arrangements. If you don't hear anything by the end of April, send me a reminder.

You probably didn't push the motor connector in far enough. There's a line that shows how far it must go for it to work.