Wolvyr

I considered this, though i'm still undecided on what to do about R22. While it seems reasonable enough that the controller may function fine without it, to me it also looks like the pads had been soldered as you can see some brown/orange discolouration from the flux on the R22 pads. However, there is no spike or obvious break point that you'd expect from a resistor that had snapped off. Even if I wanted to put a resistor in there to see if anything happens, I wouldn't know what value to use. Seems like a dead end. Thanks, i'll try this next. Can MOSFETs be tested in circuit, or do they need to be isolated like resistors? If i'm understanding this correctly, I should expect there to be a instance of 16.7A (600w/36v) being drawn from the battery as soon as i flick the ignition switch on? Even so, from what the other posters here are saying, this still shouldn't fry a 15A fuse, right? Would it e an awful idea to try out a 20A fuse and see if anything different happens, or is that asking for my MOSFETs to blow?

Thanks for the instruction! I did this and did indeed see a ranging voltage between 1 and 4 volts on the signal connection, with 1v at full throttle and 4 at no throttle. From what you were saying previously, I gather that all other throttles will give 4v at full throttle and 1v at no throttle? With the electrics taken apart so I could test the throttle, I decided to closely inspect the controller board for any abnormalities. Carefully observing each component, all seemed fine except one slightly off-coloured resistor. That is, until I looked adjacent to it - there is a resistor missing! See below for what I mean: https://drive.google.com/file/d/1tz781btKckf7zqxYbwBtKFh8n1ScIa8k/view?usp=sharing The far-right resistor is slightly off colour, and to the left of it is 2 pads with the print R22 between them. I am unaware of whether this resistor came off and is the issue, or whether it was never needed in the first place. Unfortunately, there is no circuit diagram for this board either. However, I did find another use with the same controller board (but a different issue altogether) that happened to upload a video, in which you can see his controller board. At 0.5x speed at 15 seconds in, here is what you can see on his board: https://drive.google.com/file/d/1TrMQsNCMd9PQlNAV2ET81Iy_JY6Qqhpv/view?usp=sharing It's certainly not easy to see, but im sure its there - a resistor at the pads for R22. Sadly, the resolution is so poor you can't make out the colour bands, or any colour at all for that matter. Any ideas on how I can find out what size resistor to put in the place? And just as a note, R22 does not refer to the resistor value, but is the resistor's name, as all other resistors have a name, along with their ratings printed on the silkscreen. Sadly, R22 does not have its rating printed. I'm still stuck in the dark, but i've gained two useful pieces of information today. My big question now is, would a resistor that small really cause my battery to arc at the terminals and the 15A fuse to blow?

Following your suggestion, I tried this. With the motor diconnected, the same issue persisted. While I may be no closer to the problem, I at least can rule out the motor (to some extent). Thanks for the advice! Thank you very much I'm an electrical and electronics engineering student - if I gave up, I wouldn't be able to look my lecturers in the eye aha! If it were the MOSFETS, do you know of any methods to confirm this? Wires shorting may be a possibility, though from what i've seen, there aren't any places I imagine a short could happen. The reason I think a short may be possible, is because after following Nev's advice on disconnecting the motor, I found that the fuse was actually breaking under these conditions: Battery and Ignition OFF Battery switch ON Ignition switch ON - fuse okay - twist throttle and there is no reaction from the motor - the LED's from the motor controller also have not turned on, indicating is not actually receiving power / working rock the battery side to side -fuse blows Then inspecting the connection point between the terminals of the battery and the dock connecting it to the motor controller, there are burn marks on the metal terminals, in addition to a rattly/buzzing noise at the same time as the fuse breaking. Next I'd like to test whether the throttle works, however I don't know what to expect. Is the throttle just a potentiometer, and the controller uses it alongside an on-board resistor to act as a potential divider and it reads the voltage as the input? Or does the throttle itself have both resistors, and the controller board directly reads the voltage? Perhaps it depends on the model and build of the throttle. Anyone have some experience?

Sadly, there was no branding or printing on the switch other than the words 'IGNITION' and 'OFF'. Finding the diagram seems to be futile at this point. This is precisely what I did in the end. Here's what I found out: The red and brown wires had been wired so that in every position of the switch, they're always closed circuit. I believe this was done by the previous owner, as they had lost their original key. The yellow and blue wires were only connected in one orientation of the switch, and based on the pattern of wear on the contacts, i'd assume that most of the time they were not connected together. From this, plus some information on the internet, I've concluded that red and brown definitely are power and should be closed circuit, while blue and yellow are used to determine the mode of the bike - whether its twist and go, or pedal assist. I can confirm this, which explains the blue and yellow wires. I've been doing more work on the bike, so here are my updates: The glass tube fuses I've been using are blowing one after another, and I'm running out. I have a lot of blade fuses, so I decided to wire in a blade fuse holder for easy and fast replacement of fuses as a temporary measure until I can pinpoint the fault. I also wired up a 2 position switch between the red and brown wires which were going to the ignition, so I can manually operate it for fault finding. So now equipped with easy to replace fuses and an ignition switch I began testing to work out under what conditions the fuse would blow. First, with the ignition switch off, I flicked the battery switch on. No fuse blow - naturally, since there is no current draw anyway. Next, I flicked on the ignition switch. Strangely, there was no fuse blow - unlike every attempt before. Now twisting the throttle, unfortunately there was no response from the motor. Pedalling the bike half meter, for some reason, resulted in the fuse blowing. My first guess was perhaps the motor was generating a reversed current that the fuse really did not like, which seemed odd. I have yet to find anything to confirm this, though my hunch is that this isn't the problem. After replacing the fuse, I tried again. Ignition switch off, battery switch on, then ignition switch on. Now turning the throttle, the bike is stationary, no motor reaction, and the fuse blows! No movement, no current generation! This is part of the reason I don't think the motor generating any current is the issue here, as well as the fact the controller likely has some protection from reversed currents. It almost seems like the motor controller just loves to draw massive currents at totally random times, which is making the fault finding process incredibly difficult. Some more information I've gained is that with the battery and ignition switch on, and the throttle twisted, there is no voltage making it to the battery terminals. So I can confirm that the controller is not actually sending anything to the battery. With barely a thought on what direction to go down next, I've considered a new route, though frankly I'd rather fix the original problem than have to go down this rabbit hole. So here's my plan: Since the battery itself is fine, and the motor appears to have no issues either, that leaves the motor controller as the culprit. Whether its the wiring or the controller board itself that's the problem I do not know, since I cannot find a wiring diagram anywhere, even after contacting the manufacturer. Knowing this, I should try to replace the controller. Issue 1 is that I'm not certain of whether my motor is brushed or brushless. I understand that brushed motors generally have 2 connections, and brushless 3, but my motor seems to be a strange one. There are 4 wires coming from the controller down to the motor, which go into pairs, that go to 2 terminals (2 wires per terminal). From those terminals, one wire each (so 2 wires total) go to the motor itself. I'd assume this is a brushed motor because it has two terminals, but why would there be four wires coming from the controller? Issue 2 is that I cannot confirm the power of my motor. The seller listed it as a 500w, I believe it to be a 200w, though its physically larger than a 360w hub motor I already have lying around (broken). I don't want to purchase a 200w motor controller, only to find out I'm massively hindering the motor's output. What methods/strategies can I employ to find out what the power rating of my motor is? (note - there is no printing on the motor itself, and the casing appears to be different to the hub motor in the pictures in the bike's documentation PDF I have) After I know this information I want to try out using an Arduino to control the motor using a 36V motor driver board. This way I can program in functions that I would like to have on my bike. Does anyone know if somebody has tried and/or documented this on this forum or elsewhere before? I'm looking around the internet myself but so far haven't found much. Thanks to anyone who took the time to read this long post. I've spent so many hours on this bike already, here's to hoping I get it working soon! Edit: I found <this motor driver> which seems to be perfect for this situation. Also, <this driver> seems to do the job and is significantly cheaper. Thoughts?

Thank you for this information. I suppose this has debunked my first idea. If only life were that simple. Sadly, this is such an old model that has been discontinued for a while. Even in its prime, that documentation seems to have not been in circulation. I've found the code for the ignition switch on the manual (it is PTBATLOKIGN5/21), but searching for this yields no results of worth. Has anybody had experience with a bike where every time they turn the switch on the fuse blows? I'm considering looking at getting a new motor controller, though I cannot be certain of the power of the motor so it certainly wont be easy to find a compatible one. Would it be an awful idea to bypass the fuse on the battery altogether and see if anything happens?

Don't worry, I did my research. I'm no stranger to a multi meter, and Im comfortable reading circuits. I'm 95% confident that the red and brown definitely are power connectors, and that the blue and yellow are digital signals. The red wire definitely goes directly from one of the battery terminals, while the brown goes to the motor controller. Alternatively, the blue and yellow wires are both a significantly smaller gauge, and both come from the same region (labelled P2) on the motor controller. I know the dangers of randomly connecting wires first hand! I'm not sure I follow what you mean here. Are you saying I would need to twist the throttle away from me (anti-clockwise looking at it from the right) to accelerate opposed to the traditional clockwise twist? Thank you very much for this link! The manuals do not answer my question, but they contain valuable information, nonetheless On another point, I have some theories as to why I'm having the problems I am, and was hoping to hear some input from somebody far smarter than I. Theory 1 is that upon startup, the controller draws full current for a brief moment causing the 13A fuse to break. Considering the seller listed the bike as a 500w motor, its theoreticall possible that the motor could draw up to somewhere in the region of 14A (500w/36V = 13.89). Though I very much doubt that this is either a 500w motor, or that it could really draw that kind of current, I still want to consider this as a potential cause. I will picking up a 15A fuse and testing that out to see how it goes. Any thoughts? Alternatively, theory 2 is that having the power cables that I cut from the ignition permanently closed circuit may be an unfavourable condition for the motor controller. Perhaps the key is to have the battery connected, and then have the power cables make contact via a switch, as they would have originally with the ignition switch. Any ideas on this? These are the steps I plan to take next. Anything else I should try?

Hello, I'd like to start by saying its been a while since I last posted, so if I've forgotten any important rules on where/how to post please don't hesitate to remind me. I've recently picked up a Powabyke electric bicycle - model unknown.# https://drive.google.com/file/d/11FX3RHnrYbn4WtIkfaOp8y7_aRVBgSAR/view?usp=sharing I have reason to believe it is a Powabyke Commuter, though I have no way to be certain. The battery is 36V, and the seller claimed the motor is 500w, though I quickly realised they had no clue what they were talking about and this must surely have a 200w motor in like the other Powabyke Commuters. The bike came with no charger, so after taking the battery apart, drawing up a wiring diagram and finding out which of the two types of electrical connections was the charger, I left it to charge overnight - no problems here. The next day I attached the battery to the bicycle and flicked the switch, only to realised that there was a key that the seller had lost which was required for the ignition switch. I decided on cutting out the ignition altogether and have it permanently connected, as the battery itself had its own on/off switch which i thought would be enough for now. I then planned to cut the wires before the ignition switch and have them connect to each other. See below for the wiring on the rear of the ignition switch: https://drive.google.com/file/d/1PEten0HdfpkotVQ7mpqoswFfmCeN0fN3/view?usp=sharing After spending some hours looking for documentation/a wiring diagram for the K3602 motor controller on the bicycle, I failed to find anything remotely helpful. I decided to take it into my own hands and make a few assumptions. I first assumed that the red and brown were obviously the 36v power, and that I should just connect these directly, and secondly that the yellow and blue were just a digital signal to alert the controller that the ignition was in the 'ON' state. Again, I had no wiring diagram, so was only using intuition. Having no other leads on how to go about this, I went forward on connecting those wires, like so: https://drive.google.com/file/d/1xGplslkdJo7zIoHGsLolHgfgtCfoSEMv/view?usp=sharing (Red going straight to brown, and blue going straight to yellow - I know the insulation tape looks awful here but it was only to test whether this would work). I reassembled the electronics on the frame and attached the battery. Making sure the fuse on the battery was fine, and the battery was still outputting at least 36v, I attached it, flicked the on switch, and hoped for the best. To my frustration - nothing! Checked the battery output - 0v. Checked the fuse - blown. After replacing the fuse and trying again, history only repeated itself. Fuse after fuse was blowing after connecting it to the controller and flicking the switch. I then tried removing the blue and yellow wires altogether to see if that made a difference, which it did not. The motor does not make any movement - though I know it is functional as bypassing the motor controller altogether does cause it to spin. I cannot find any documentation on this bicycle or its controller out there, though I have contacted Powabyke via email and am waiting for their response. Does anybody have any clue why fuse after fuse keeps blowing? Did I make a stupid mistake while reconnecting the wires from the ignition switch? Any suggestions at all? I am very grateful for any help anybody may be able to offer, so dont be shy! Thank you for taking the time to read this and have a good day

What makes a hub motor the "right" motor? So having gears makes it suitable for hill climbing, but compromises speed on the flat? That makes sense, hopefully I got it right. Also, where do you guys suggest sourcing an ebike motor? eBay rarely says whether it is geared or gearless, or any real useful information. The hub motor I was originally looking at was a 1000W gearless motor, so I guess thats out of the picture now. My requirements are a max speed of around 25mph and ability to climb hills, and preferably a range of at least 6miles. I guess the range entirely depends on the battery but I still thought I'd add it in. Will a 250w motor achieve this for me? Was the 1kw overkill? Can I buy this kit on eBay (or elsewhere) for <£250? I'm very sorry if it seems like I'm having you guys do my research instead of doing it myself, it's just I thought that the 1kw motor I had in mind was perfect and only now have I found out it is not. I really do appreciate everyone's input

I live in East Anglia, but there are still some hills, especially one large one to get out of my small town. So you're saying that going with the 1000W hub motor will not help at all?

Please forgive me atrocious electronics knowledge, but won't raising the voltage passed also raise the amps?

So I see that this is a very good option, but what exactly is the issue with a 1000W hub motor? Why choose the 250W mid drive over the 1000W hub or vice versa?

Aha I appreciate the concerns, but I will be using disc brakes, and I don't see how the pedals affect anything? I see, but I'm not interested in mid drive systems, as i'm only capable of something as simple as a hub motor. Will the same hold true for a 250W hub motor from eBay?

I have a nice, straight, flat, mostly unused cycle path of tarmac that goes for miles, its perfect for high speed cycling. Won't putting 48V through a 250W motor absolutely destroy it? I imagined it would overheat, melt off the waxy coating of the copper wires in the electromagnet and short circuit the whole thing in minutes?

Ahahaha, thank you for pointing that out! I would have been very annoyed if I had gone through and purchased that :')

Im looking for a build that has the capacity to reach ~30mph on flat, but will use it almost always in the 5-15mph area. I just want the ability to go high speed if I ever needed to, in a safe environment of course. Im guessing the 250W set up you described is not suitable for this? What are the cons of a 1000W motor, and how would I know if it is direct drive? It's a rear wheel hub motor that im interested in, if that helps at all.

You mentioned putting 48v through a 250W motor and having similar performance to a 1000W? Would this not be extremely dangerous and risk burning the motor out? It sounds like youre saying that there are a lot of negatives with going with 1000W, to my understanding 1000W was the best option for a high power build, was i wrong? Also, thanks everyone for the responses, they all really helped. I've decided on just going with lithium and biting the bullet, accepting my woes with the price. I have found something that seems somewhat promising, but of course, I ask that you experts take a look: http://www.dhgate.com/product/e-bike-li-ion-battery-case-24v-36v-48v-battery/381050241.html#s1-2-1b;searl|1028640759 at around £80 this seems too good to be true, is it? Thanks again everyone

Edit: Looking on hobby King, found these http://www.hobbyking.com/mobile/viewproduct.asp?idproduct=18495 Using two of these to bring the voltage close to 48v, what do you guys think?

If I make the box 110 and I still come into problems with obstruction, is there still a method of spacing out the pedal levers a little? Or do I just need to bed them? Thanks for the response 5.8ah just seems so small :'( and then there's the problem of balance charging. I have very little experience here and I felt like dealing with SLAs required less knowledge for a beginner - just solder up the terminals and you're ready. I understand that with lithium chemistry batteries you need to balance charge and soldering the terminals can head the chemicals and reduce its life. Any suggestions for an absolute beginner like me when it comes to lithium cells?

As a side note, what are your feelings on using these SLA batteries? I'm using them because they're the only thing in my price range - £200 for a lithium just seems ridiculous to me and right now it's out of my budget. I have serious considerations for eventually building my own battery from 18650's, but that won't be for a while. Will I get particularly good mileage out of these batteries? What are the measurable signs that an SLA battery is degrading? (like voltage, resistance etc)

I have made plans to put together a bike using a Beach Cruiser style bicycle and a 1000w 48v ebike kit, all from eBay. In this build, I plan to build a fibreglass box for the centre of the frame to hold the batteries and speed controller, but have run into some design problems. I will be using 4x 12v 12Ah SLA Lucas to produce one 48v battery. I have based my designs around the size specifications of these cells ( 151x100x100mm), so the width of this box will be 150mm to accomodate for the 100mm width of the batteries and any wiring to the sides. The big problem is that I worry that the bicycle pedals will not be able to fully rotate as they will be obstructed by the box. Is there any such technique or product I can use to space out the pedals about 2 cm on either side? Would i have to bend the pedals themselves? I will attach images of the design so you guys can see what i mean. All suggestions appreciated, thanks for reading Edit: Added images

This is questionable, as the juddering was not present for the first half of a some 3 mile journey at full throttle. The battery had performed fine at that point, and the juddering only occurred when I tried taking it up a hill. Since that Hill, it has persisted.

How would one go about determining whether these batteries are knackered? Does the fact they hold their voltage not give any indication that they are in good health? I'm assuming the only true way to test this is by sourcing some all new batteries and testing whether the juddering still persists?

The bike does not use any stock battery. When I bought it second hand, it had a slightly beaten up silver plastic case covered in duck tape, holding three LSLA 12-12 12v 12ah Lucas lead acid batteries, producing one 36v battery to power the 36v motor. There are two individual wires going from the controller to the motor, one red and one black. I have tested the voltage of each of the 12v batteries and they appear fine. Is this enough info? I will check if I have a picture Edit: It might also help to know that with the help of someone better suited to the task than I, the batteries have been resoldered and all cables replaced as they were in dreadful shape beforehand. All new fuse, wires, switch, soldering, the only thing the same is the beaten up box and the batteries them self, which appear to hold a charge well.

I apologise for asking, but could you maybe explain what an SLA and LVC is? Edit: I see SLA is sealed lead acid, still researching for LVC And LVC would be low voltage cutoff. So how exactly would one repair the problem with the LVC?

I struggle to see that a faulty connection could be the cause here due to the fact the wheel spins without judders when the heavy load is removed by lifting the wheel. I do no believe there is erratic phase firing because of this fact, as the wheel still spins at a constant speed when under less stress. However, I will still investigate this possibility. When performing repairs on the bike, I noticed the wires to the motor were exposed and had been causing many many broken fuses for its previous owner. I attempted to open the motor casing and replace the wires altogether, though failed to take apart the casing. I simply could not pry the face off after removing the screws. Any suggestions? So Instead, I ran heatshrink along each wire separately as far down as I could and then heat shrinked the two wires into one. I suppose it is more than possible there is still exposed wiring further down into the motor that is causing a problem. Even so, wouldn't that just cause the fuse to break, breaking the whole circuit and stopping all power to the motor altogether? Edit: bad autocorrects Another edit: I have been foolish. Before I said that the juddering did not occur when heavy loads were removed. I left the batteries to charge a little despite the charger showing the green light, in case they needed more power. This had no effect. However, when testing whether it did, I found that if I lift the back wheel and apply the throttle straight to max, the juddering >does< still happen, despite the load being removed. However, if I give it a fast, but still gradual and paced twist to max, the juddering does not occur when the wheel is lifted. I am sorry for having any doubt, Mr flecc.