Help!! My sunlova kit stopped working!

[John L]

I was very pleased with myself this morning heading off on my 16 mile commute to work - today I was going to pass the 1000 mile mark. I was well kitted out for the cold and looking forward to the spin. But a mile out from home I lost power. Instant power loss.

The battery indicator on the battery shows fully charged but no leds light up on the throttle indicator. I recently reconnected all the wiring (after it got wet and stopped previously) and put silicone grease around all the new connections so the wiring should be good.

The only thing out of the ordinary recently was a noticeable "dry" noise (just a sound a bit louder than normal really - hard to describe!) from the motor when it was running between 16 -18mph for the last week or so. I tried last weekend to have a look in the motor to see if the gear wheels needed grease but soon realised that I didn't have the right tool to remove the cover plate.

I will check the wiring again tomorrow but I'll be amazed if thats the problem. I'm more worried that the controller might be burned out. Is this likely or has anyone come across something similar? Any suggestions would be very much appreciated.

John

 

[Dynamic Position]

From the symptoms you describe I would check to see if a fuse has blown. Check battery first.

 

[John L]

From the symptoms you describe I would check to see if a fuse has blown. Check battery first.

A blown fuse might well be it but I didn't see anything like a fuse when I was fitting the kit - uumm thinking about it now perhaps there is a fuse in the casing where the battery connects. I'll check it out in the morning

John

 

[John L]

Guys - now I'm kinda concerned

I was away at the weekend and only got to checking things out today. First thing I checked was whether there as any power going to the controller. I put a meter across the leads - nothing!

I took the battery out and checked whether there was any power at the battery terminal - nothing.

i found that there was a fuse built into the battery case - i took that out and the fuse is fine.

The battery indicator shows fully charged. I reconnected it to the charger in case it was a bit low but it too shows that the battery is charged.

I'm at a loss now - I've emailed sunlova and I'm waiting to hear from them.

Anyone here any ideas?

John

 

[NRG]

This may sound daft but is there an on/off switch on the battery? If not and the fuse is OK, it could be a BMS issue.

 

[John L]

This may sound daft but is there an on/off switch on the battery? If not and the fuse is OK, it could be a BMS issue.

Thanks NRG. Unfortunately there is no on/off switch on the battery unless its hidden .

Assuming that the battery indicator and the charger are right - the cells seem to be fully charged. So the problem seems to be between the battery cells and the output leads. I daren't dismantle the battery at this stage for fear of breaking the warranty (if that means anything ) Not sure what a BMS is or where it is?

John

 

[onmebike]

In the absence of a switch it sounds like it is a bms problem. The bms is a circuit usually built into the battery case that monitors charge state of cells to ensure they are balanced and do not overcharge. It also protects the battery from over discharge by cutting output when voltage drops to a certain level. If the battery is under warranty it will need to go back to supplier.

 

[jbond]

Seems pretty clear to me. If the battery appears charged but has no voltage on the output it's damaged. If it's still under warranty, get it replaced. If it's no longer under warranty have a look inside. It wouldn't surprise me if one of the connections between the cells is broken and/or one of the links from the cells to the BMS.

 

[vhfman]

Are you sure there is no ON/OFF switch on the battery? They are usually part of the battery lock mechanism. On the batteries I have the power ON switch is the next turn of the key after the battery is locked (like a car ignition switch). It could be that switch that’s faulty, as you say the LEDs on the battery show it to have charge, I would think the BMS is probably OK, if those LEDs are on the output prior to the key lockswitch. Make sure you turned it on before trying to measure output voltage. I presume you checked the fuse for continuity with a meter not just visually.
I just checked one of my batteries has 2 fuses one hidden under the handle.

 

[John L]

In the absence of a switch it sounds like it is a bms problem. The bms is a circuit usually built into the battery case that monitors charge state of cells to ensure they are balanced and do not overcharge. It also protects the battery from over discharge by cutting output when voltage drops to a certain level. If the battery is under warranty it will need to go back to supplier.

That sounds about right. The battery is under warranty still (kit bought in June) - I have contacted sunlova and they came back to me last night with a few questions which I have answered. I'll wait to see what they suggest. Thanks.

John

 

[John L]

Seems pretty clear to me. If the battery appears charged but has no voltage on the output it's damaged. If it's still under warranty, get it replaced. If it's no longer under warranty have a look inside. It wouldn't surprise me if one of the connections between the cells is broken and/or one of the links from the cells to the BMS.

Thanks - hopefully sunlova will replace it. Its amazing what goes into a battery! As a newbie it looks like just a big lump of a battery - what can go wrong?? A bit more than I thought!!

John

 

[JohnD]

key

i would think the key is the on/off switch - mine has 3 positions the last one being power on.

 

[John L]

Are you sure there is no ON/OFF switch on the battery? They are usually part of the battery lock mechanism. On the batteries I have the power ON switch is the next turn of the key after the battery is locked (like a car ignition switch). It could be that switch that’s faulty, as you say the LEDs on the battery show it to have charge, I would think the BMS is probably OK, if those LEDs are on the output prior to the key lockswitch. Make sure you turned it on before trying to measure output voltage. I presume you checked the fuse for continuity with a meter not just visually.
I just checked one of my batteries has 2 fuses one hidden under the handle.

Thanks vhfman. The battery I have is simpler design. The switch is on the carrier where the battery plugs in. The fuse is pretty much as in your photo but apart from the charging point there isn't anything else on the battery. A few photos.. (sorry about the quality - the light was pretty bad)

I put the meter across the fuse and its fine (until then I was beginning to think the meter was broken!!) I really hope sunlova look after this for me. The battery is by far the most expensive part to replace.

Thanks

John

 

[John L]

i would think the key is the on/off switch - mine has 3 positions the last one being power on.

Hi John - unfortunately the on/off switch is 0 or I - just two positions. As far as I can tell though power isn't getting as far as the switch .

I've just replaced the wheel with the hub motor for the original wheel which came with the bike. Feels much lighter but I'm in two minds about the 32 mile round trip to work tomorrow without that motor!! I'll go for a little spin today to see whether I feel confident enough

Thanks

John

 

[John L]

Well the battery is on the way back to sunlova who have undertaken to replace it - a little expensive to post back a battery from Ireland but better than buying a new one!

So I'll be without the use of the motor for a week or two

Nevertheless I did the 32 mile round trip to work today under my own steam and while I was tired I was able for it. Before I converted the bike I would not have been - goes to show that even under assist you are getting a decent bit of exercise. If I can keep it going I'll be flying when the new battery arrives

John

 

[John L]

Hi guys

Well thankfully a new battery arrived today It took a while becasue sunlova didn't have any in stock. The new battery is much the same as the orginal except it has an on/off switch. Sunlova were very apologetic for the delay in getting a battery to me and by way of compensation they agreed to provide me with a new charger. I can now leave a charger at work and charge there whenever I want.

Only problem is that I can't get out on the bike with the ice! Very little salting here in my area and its just too dangerous. God tho it could be another week before I do get out.

John