MJ850 - cheap. Too good to be true?

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Thanks GCBryan,

Good to hear I am not the only one with problems, although these are different, I guess.

I'll have the batteries tested with some load as well... I might actually be able to swap parts with someone else, to exclude this from the list.

Cheers!
 
Thanks GCBryan,

Good to hear I am not the only one with problems, although these are different, I guess.

I'll have the batteries tested with some load as well... I might actually be able to swap parts with someone else, to exclude this from the list.

Cheers!

Be sure to report back. I think the battery issue is just unstable chemistry with some individual batteries. I wasn't the only one who had that same battery problem with the batteries that came with my light. I (and others) just switched to a different brand and that solved that problem. Good luck!
 
Well, after 2.75 dives my Photic SST-50 1200-Lumen LED Dive Light from Novae Products died. The night dive was going great tonight, then darkness. I am sure glad I brought my backup.

What happens when the batteries get low? Would the light go dim or just shut off like it did?

I know the batteries were not fully charged at the start of the dive. Even though I was getting 4 flashes on the battery power check mode before the dive. And it died about 35 minutes into the dive. I would hope that there would be a warning of some sort before the light would just turn off on low power.
 
Well, after 2.75 dives my Photic SST-50 1200-Lumen LED Dive Light from Novae Products died. The night dive was going great tonight, then darkness. I am sure glad I brought my backup.

What happens when the batteries get low? Would the light go dim or just shut off like it did?

I know the batteries were not fully charged at the start of the dive. Even though I was getting 4 flashes on the battery power check mode before the dive. And it died about 35 minutes into the dive. I would hope that there would be a warning of some sort before the light would just turn off on low power.

If you have "protected" batteries that's exactly what happens. Lithium-ion batteries shouldn't be allowed to overcharge or to run down too much so there is a protection circuit on "protected" batteries that cuts power when either of those two things happen. You have to put the batteries back on the charger to get them to reset.
 
That is probably what happened. I did not recharge the batteries last night, but when I got up this morning I tried them again. The light came on and blinked 2 times on the battery mode a few times and then went to a single blink.

Could the batteries reset by having them sit overnight?

I just looked at the Novae site and they have new batteries for sale that say they are •Protected against: overcharge, overdischarge, short circuit. These are the replacement batteries for the light, so I will make a wild assumption that these were also included with the light.
 
OK.. next report: I just sent the MJ850 to the manufacturer after some mail discussions with them. Now tension increases, will they actually repair the light and return it?

Place your bets please!:D

More to follow.
 
Hope all goes well. I guess my problem was just the batteries hitting the low voltage protection. I charged the batteries and went on a dive Wednesday night and it worked fine.

I am not convinced about the battery level flash feature though. The night my light died it flashed a full charge but died after 35 minutes or so. My last dive was only about 35 minutes and when I got home it still flashed a full charge.

I also noticed that my batteries seem to regain voltage if they just sit. Back to when my light died, I let the batteries sit outside the light for 3 days and the worked again and both batteries measured over 3 volts.

I think I just need to find more info on how these batteries work....
 
Still waiting for it, Beekeeper5, I was a bit late sending this to China... Tracking information says the package is in China (since 9-5) but not yet delivered. I guess it is on some sort of old cart being transported by a donkey... to end up at an old shack .. but it's not there yet.

I will keep you posted in this topic...

Cheers,

Maurice
 
Couple quick things I have seen.

The MJ850 is known for flooding, but new MJ900 seems to fix this issue (per Magic Shine). I haven't personally used the dive lights.

I work with the manufacture quite a bit on their cycling lights (I work at a bike shop). The bike lights throw a lot of light for the money and have a decent durability. When a customer had a problem, they always stood behind their product. For the price, knowing the manufacture, I'd be worth giving it a try.
 
https://www.shearwater.com/products/peregrine/

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