Magicshine battery dying quickly

[Deleted member 4366]

Mine was the same as yours, Tilson. Bright enough on setting one, very bright (more than you neeed) on setting 2, and the same brightness but more spread on setting 3.

 

[tillson]

Mine was the same as yours, Tilson. Bright enough on setting one, very bright (more than you neeed) on setting 2, and the same brightness but more spread on setting 3.

That sounds about right. It's very similar to nuclear fusion on setting 3. A mini star on your handlebars!

 

[halfer]

Right, so I ordered the expensive Open Light Systems battery, and - as Murphy's Law would have it - it seems that there is a problem with my light unit. I plugged in the new battery, and it lit up at usual brightness for a few minutes, and then reduced to an incredibly dim level (about the same you'd get from a 10p white LED from Maplin). The hi/lo/flash modes still work, except at the hugely attenuated level, and the health LED on the back of the light lights in green as it should.

I plugged in the old battery, and now the lamp unit does the same here - the battery LED on the back is green, and the lamp itself is the same level of dim output. I get 8.0V on the old battery display, so I wonder if a lamp fault was resetting the BMS in the old battery, hence it working a couple of weeks ago for several minutes at a time before turning off. (Now it won't even do that!)

Does it sound like purchasing a new head would be the solution? (1000 lumens seems to have replaced 900). Not sure whether to use the 7-day money back guarantee on the new battery, but having a spare would be useful...

 

[cwah]

Nothing's better than using a DC-DC from the main battery. No more hassle to change the batteries, no more worries about batteries drying out.

 

[halfer]

I agree in theory, and in fact I did that with a home-made rear light on my previous bike. But on my new Ave, cutting into a power line will almost certainly invalidate the 2-year warranty, and I have around 22 months left. So, I'm sticking with separate batteries at the mo.

Anyone experienced the problem I describe with my lamp unit?

 

[Deleted member 4366]

Right, so I ordered the expensive Open Light Systems battery, and - as Murphy's Law would have it - it seems that there is a problem with my light unit. I plugged in the new battery, and it lit up at usual brightness for a few minutes, and then reduced to an incredibly dim level (about the same you'd get from a 10p white LED from Maplin). The hi/lo/flash modes still work, except at the hugely attenuated level, and the health LED on the back of the light lights in green as it should.

I plugged in the old battery, and now the lamp unit does the same here - the battery LED on the back is green, and the lamp itself is the same level of dim output. I get 8.0V on the old battery display, so I wonder if a lamp fault was resetting the BMS in the old battery, hence it working a couple of weeks ago for several minutes at a time before turning off. (Now it won't even do that!)

Does it sound like purchasing a new head would be the solution? (1000 lumens seems to have replaced 900). Not sure whether to use the 7-day money back guarantee on the new battery, but having a spare would be useful...

I can't understand why you want to keep throwing your money away. I got two of the lights (the same as the Magic Shine head) from Aliexpress for £30 (for two) and they came with 4 cell batteries, and you just spent £45 on one battery, By the time you've bought the head for £45, you'll have spent £90 and still might have a non-functioning light, when you could've had six functioning ones.

 

[tillson]

Nothing's better than using a DC-DC from the main battery. No more hassle to change the batteries, no more worries about batteries drying out.

With the 3 x LED lamp unit, I think that the battery which is supplied is too small. When used on level 2 (2 LEDs) it just about lasts for one hour. This isn't long enough for my trip too and from work, so I need to take a second battery with me.

To get the best out of this light you will need to get a bigger battery or as cwah says, supply it from the bike battery. I am waiting for delivery of the DC-DC converter which Jeremy suggested, which will hopefully improve matters. I don't know about the Bosch system, but I am confident that I can pick up a feed off back of the the Panasonic battery connector without causing any permanent disruption to the wiring, so it should be easily reversible. Maybe woth looking more closely at the Bosch battery connector if this is something you are considering.

 

[halfer]

I can't understand why you want to keep throwing your money away. I got two of the lights (the same as the Magic Shine head) from Aliexpress for £30 (for two) and they came with 4 cell batteries, and you just spent £45 on one battery, By the time you've bought the head for £45, you'll have spent £90 and still might have a non-functioning light, when you could've had six functioning ones.

I'll read that as a peculiar turn of phrase, rather than you actually believing I enjoy wasting money. As I said earlier, I made the choice to pay for a quality battery, rather than have a cheap one explode on me (there's a recent forum thread about this actually having happened in the UK, think it's on Endless Sphere). I also don't want to keep buying batteries and/or devices that will end up in electronic landfill every couple of years. Perhaps the economics are such that I have little choice, which would be a pity.

 

[Deleted member 4366]

I've been using these lights for over a year, and so far I haven't put any batteries in land-fill, compared with one of yours ready for it by the look of it, and maybe another one about to go in.

The only point I was trying to make above is that although cheap and chearful, these lights do work.

 

[tillson]

The only point I was trying to make above is that although cheap and chearful, these lights do work.

I'll second that. My first light is still working well with the original battery. This new 3 LED light also works well, but the downside is that the battery does not have sufficient capacity to run it for more than an hour. This is a mis-match of light unit to battery issue rather than anything to do with quality.

 

[tillson]

I've not tested this, but it might well do the job: 12V 24V 36V 48V to 9V 3A DC-DC Adjustable HRD Converter Step Down Power Module | eBay

The light will probably be OK on 9V I'd have thought, and unlike many of these cheap switched mode converters this one seems to accept a higher enough input voltage range for a 36V nominal ebike battery.

My plan is to run my light from one of the spare 5V DC DC converters left over from one of my chargers, but these are a massive overkill really (they are rated at 36 to 72V input, 16A output!). Unfortunately 5V isn't enough to run the three LED light, it looks like that needs 8.4V, from the spec.

I ordered the DC-DC converter above and it works well with the Cree T6 Led lights, even the supposedly 4000 Lumen one. I've built the converter into a weatherproof box and brought out two output leads with jack plug type connectors to power the front and rear lights and one input lead / jack plug for the battery feed. I did this so that I can easily remove the converter from the bike.