Hello folks. Newbie here. Here goes; I bought a 350W mid drive kit and 12ah battery from PSWPower via their German warehouse. I fitted evrything to my old-but-good Specialized Rockhopper Pro. Motor went in without too much trouble. Charged battery overnight - loads of green lights, put it on the bike - nothing. Can't even get the display to wake up. I checked the battery plate connections and all other wire connections and changed the in-line blade fuse, and tried again. Nothing. Whole system downstream from the battery seems dead. I suppose I could simply return the whole kit to PSPPower, but the problem may be something stupid I've done that requires a simple fix from me. Over to you good folks - all suggestions gratefully received.
New Tongsheng mid drive kit won't power up
- Thread starter Sailorbass
- Start date
Did you switch the battery on?
The LCD runs directly from the battery connection, so if it doesn't come on, you have a connection fault somewhere. You need to use a meter to follow the voltage from the battery to see where the break is.
The LCD runs directly from the battery connection, so if it doesn't come on, you have a connection fault somewhere. You need to use a meter to follow the voltage from the battery to see where the break is.
@vfr400. Thank you for your reply. Yes - I turned the battery on and off, and all that. I also suspect it's a dodgy connection somewhere. The main connectors between the battery and the motor looked pretty cheap and nasty - one fell off when I tried to push-fit it. I replaced that one with a cable connector block swathed in waterproof tape.
The connector from the speed sensor to the display proved troublesome. The 5 tiny pins were bent, and almost impossible to line up to the female side of the push fit. How important is the speed sensor? I'd happily leave it off if all it does is send speed info to the display.
The connector from the speed sensor to the display proved troublesome. The 5 tiny pins were bent, and almost impossible to line up to the female side of the push fit. How important is the speed sensor? I'd happily leave it off if all it does is send speed info to the display.
have you got a volt meter?
if you have, check first the output voltage of the battery.
Next, take some close up pictures of the LCD pins.
If they are bent - your problem is there.
if you have, check first the output voltage of the battery.
Next, take some close up pictures of the LCD pins.
If they are bent - your problem is there.
Thank you Andy. Turns out that one of the pins in the connector between the motor and the display was bent. I've manged to straighten it, and the display is now live. However, with the bike suspended, I can pedal the back wheel freely, but I'm not feeling any discernible assistance. Does the display have to be "initialised" or calibrated, or some such thing? I vaguely remember reading that somewhere.
Also, because of my ham-fistedness, I bent the pins in the speed sensor connector. Will the system work OK without the speed sensor? I'd happily do without speed data on the display, if that's all it does.
Also, because of my ham-fistedness, I bent the pins in the speed sensor connector. Will the system work OK without the speed sensor? I'd happily do without speed data on the display, if that's all it does.
If you bent the pins far enough in the connextor to shorrt the battery pin to any of the others, you might have wiped out the software in the controller and/or the LCD. The LCD will probably be OK if all the features are showing, including battery level, and you can move up and down the PAS levels. The controller side of the connector has holes rather than pins, so there's less chance of damaging anything on that side, but it's not impossible.
Are you turning the crank by hand with the back wheel off the floor, expecting to feel the motor "kick in"?
If so, don't forget it's a torque-sensing motor. It detects the twist in the crank to sense torque, then multiplies it. If there's no resistance on the back wheel you won't twist the crank enough to activate the torque sensor.
Depending on your display, you can activate "walk assist" to test the motor. Or just use the throttle if you've got one...
Gavin - many thanks for your reply. Andy at Whoosh bikes has also been extremely helpful about this. I now realise that spinning the cranks by hand with the back wheel off the ground wasn't going to activate the motor. I'll get out for a spin round the block today and, fingers crossed, all should be well. Probably.
Ha! It works! Took it out this afternoon and all's well. My impressions: The torque sensing system is fairly sensitive - you do have to put some effort in to activate the motor. I was doing some gentle trail biking around my local park - hilly and muddy - and I didn't get above level 2 assist. I quickly decided the best way to ride was to treat it as normal bike - use the gears as you would normally and, when you're on the hill-climber, introduce the motor in steps. If you don't do this, it's very easy to leave it in a middle gear and use the assist more, which is probably not good for the chain line. When you stop pedalling, the motor cuts out automatically - so, no need for brakes that shut the motor off, providing you're not pedalling while braking. If you stop with the assist turned on, you do need to be a little wary when you set off again because you'll get a shove whether you want it or not. A couple of times I stopped at junction and when I set off again, I shot across to the other side of the lane. The motor is very quiet. In levels 1 and 2, there is a very quiet buzz-hum, but nothing more. I left the speed sensor disconnected, and the whole system seemed to behave itself. No speed data at the display, but I'm fine with that.
I was out for 2 hours using the assist system about half of that time, I'd guess. Battery indicator is still showing all four bars at the end of the ride.
Total spend = £400, including the full kit (motor, battery, all wiring, display), a few tools to get the old cranks and bottom bracket off, and £30 for the bike shop to sort out my ham fistedness. Bike weighs 17.5 Kgs.
So, all in all, I'm very pleased and impressed. It's given me what I was hoping for - a renewed interest in biking lanes and tracks - not as a kamikaze eco warrior, but as an aging 64 year old who enjoys fresh air and hill views.
Thank you to everybody here who came up with suggestions and help. I've learned a huge amount about electric mountain bikes, and I'm now looking forward to tomorrow's ride.
Steve
I was out for 2 hours using the assist system about half of that time, I'd guess. Battery indicator is still showing all four bars at the end of the ride.
Total spend = £400, including the full kit (motor, battery, all wiring, display), a few tools to get the old cranks and bottom bracket off, and £30 for the bike shop to sort out my ham fistedness. Bike weighs 17.5 Kgs.
So, all in all, I'm very pleased and impressed. It's given me what I was hoping for - a renewed interest in biking lanes and tracks - not as a kamikaze eco warrior, but as an aging 64 year old who enjoys fresh air and hill views.
Thank you to everybody here who came up with suggestions and help. I've learned a huge amount about electric mountain bikes, and I'm now looking forward to tomorrow's ride.
Steve
Hi,
I am not 100% certain but I think the controller does use the speed input, as well as torque, to compute the amount of assist needed. If so it may well work better with the sensor connected but from your experience it works well enough without it. Of course the speed limit will not be operational so the bike is technically illegal if used on roads.
I am not 100% certain but I think the controller does use the speed input, as well as torque, to compute the amount of assist needed. If so it may well work better with the sensor connected but from your experience it works well enough without it. Of course the speed limit will not be operational so the bike is technically illegal if used on roads.
Thought I'd cracked this. The system seemed to be working well, but there's now a battery charging problem. I went for a ride, came back with battery showing 3/4 charge on its own indicator lights, and on the LCD. Next day - nothing. Battery completely dead. Charger shows red light for a short while, then turns green after 2 or 3 minutes. I've tried charging the battery on and off the bike, but with the same result. I bought the battery and the charger at the same time from the same supplier, last month, and I've only charged the battery once. My concern is that the battery lost a load of charge overnight, and now won't charge. Does this suggest a problem with the battery? Just so you know, I don't have a multimeter....
Here's the battery: http://www.pswpower.com/ven.php?cargo.2020-68-8q4w
Here's the battery: http://www.pswpower.com/ven.php?cargo.2020-68-8q4w
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You clearly have a problem, but don't make assumptions based on LEDs. Get a meter and measure the voltage on the charge socket and battery terminals, which will show if you have a connection fault or blown fuse.
I'm going to send the battery and charger back to PSWPower for repair under warranty. Apparently, they need to go back to PSW German warehouse. Does anybody have the address, please?
PSWPower want me to send multimeter readings. I've just bought a multimeter thingy from Screwfix, but I have no idea how to use it to answer questions: Is the discharge normal? What is the discharge port voltage? Is the fuse normal?
Can somebody please tell me where to put black and red test prongs, and what to select on the rotary switch for each question? I have no experience of using these things at all, and I don't want to damage anything, or myself.
Can somebody please tell me where to put black and red test prongs, and what to select on the rotary switch for each question? I have no experience of using these things at all, and I don't want to damage anything, or myself.
Attachments
Set the meter to 200v DC (11 o'clock position). Put the probes on the two outer battery contacts. Note the voltage. Put the battery in its receiver and measure again on the connectors on the red and black wires. Note the voltage.
Show a picture of your charge socket on the battery so we know which version you have,
Show a picture of your charge socket on the battery so we know which version you have,
Hi, I got a complete kit (similar - but rear wheel) from PSW power and found them helpful, but I've not needed their warranty returns.
For the multimeter, suggest you get used to it by practicing with a small battery (from a torch / TV-remote etc?), anything you have handy, 1.5 volt AA or 9 volt PP3 are common.
You have the cables in the correct holes (if you use the meter and it displays a negative number just swap the cables to show a positive reading)
When setting the meter, you need to tell it what voltage to expect. It has pre-set voltages so pick a number slightly higher than your battery.
Image the dial of the meter is a clock face,
- to check 1.5 volt or 9 volt batteries use your "20" setting at 10 o'clock position
- to check you 36 volt bike battery use your "200" setting at 11 o'clock position
A helpful guide (especially the "Measuring a battery voltage" for the bit you need) https://randomnerdtutorials.com/how-to-use-a-multimeter/
Edit: just to do what VFR400 says above to test the battery, look at the link I included if you want to understand what is happening.
For the multimeter, suggest you get used to it by practicing with a small battery (from a torch / TV-remote etc?), anything you have handy, 1.5 volt AA or 9 volt PP3 are common.
You have the cables in the correct holes (if you use the meter and it displays a negative number just swap the cables to show a positive reading)
When setting the meter, you need to tell it what voltage to expect. It has pre-set voltages so pick a number slightly higher than your battery.
Image the dial of the meter is a clock face,
- to check 1.5 volt or 9 volt batteries use your "20" setting at 10 o'clock position
- to check you 36 volt bike battery use your "200" setting at 11 o'clock position
A helpful guide (especially the "Measuring a battery voltage" for the bit you need) https://randomnerdtutorials.com/how-to-use-a-multimeter/
Edit: just to do what VFR400 says above to test the battery, look at the link I included if you want to understand what is happening.
Thank you for your help. I did some reading, watched some YouTube videos, and practised with some torch batteries.
Here's what I have so far with the bike kit. Battery off the bike: Voltage reading across battery terminals is 1.2 - the same whether battery is turned on or off. Bit difficult to get to the red and black wires from the battery cradle on the bike frame because the connectors are swathed in electrical tape.
Charger: I think it's a "DC connector"" Plugged it in, got red light for about 1 minute, then it turned green. I put the red probe inside the connector, and the black probe on the outside. Voltage reading = 41.8, when charger showing green light.
Tested blade fuse - got a reading close to zero (same as when I touch the red and black probes together), which I think indicates that the fuse is OK.
Here's what I have so far with the bike kit. Battery off the bike: Voltage reading across battery terminals is 1.2 - the same whether battery is turned on or off. Bit difficult to get to the red and black wires from the battery cradle on the bike frame because the connectors are swathed in electrical tape.
Charger: I think it's a "DC connector"" Plugged it in, got red light for about 1 minute, then it turned green. I put the red probe inside the connector, and the black probe on the outside. Voltage reading = 41.8, when charger showing green light.
Tested blade fuse - got a reading close to zero (same as when I touch the red and black probes together), which I think indicates that the fuse is OK.
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The meter is working fine and shows the charger and fuse are ok, now you know how to use a meter will be very useful !
When you plug the charger into the mains the light should go green. Then connect the battery and it should go red until fully charged - then it goes green again. Does your charger go red when you connect the battery?
For info I have a similar battery and it reads between 35-41 volts (depending if discharged or fully charged). I'd expect even a scrap battery to show over 30 volts.
Your reading is so low it says the problem is something to do with the battery (or the way it's being tested) not the other parts of the system. Hopefully there's a simple solution!
Other folk have more experience so I'll let them suggest the next steps. Hope you get it sorted
When you plug the charger into the mains the light should go green. Then connect the battery and it should go red until fully charged - then it goes green again. Does your charger go red when you connect the battery?
For info I have a similar battery and it reads between 35-41 volts (depending if discharged or fully charged). I'd expect even a scrap battery to show over 30 volts.
Your reading is so low it says the problem is something to do with the battery (or the way it's being tested) not the other parts of the system. Hopefully there's a simple solution!
Other folk have more experience so I'll let them suggest the next steps. Hope you get it sorted
When I plug the charger into the mains without the battery connected, the light goes red for about a minute, then goes green. The light then stays green. When I push the battery indicator button on the battery itself, no lights come on at all and, when on the bike, the LCD shows nothing at all. 
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