Mag85 problem

[wacbzz]

Hi all. I've got a problem with a Mag85 that I built (with some help) and I figured that you guys could help me figure out what is up.

The light was put together over a year ago - I believe. I cannot remember the exact specifications, but I used a FM battery holder (9 GP NiMH 2000 rechargables), a KIU attached to an AWR hotdriver (yes, I actually got mine:naughty. I used the light two times or so but never used it to failure/auto turn off. It has been sitting on my dresser ever since.

The other day, I hooked it up to the charger, waited for the green light and turned it on. The light shut off almost immediately. I waited until the next day and stuck it back on the charger and waited for the red to turn to green. Then, the same thing; not an instant flash, but rather turn on, wait 3 seconds, then shut off. Now, last night, I again put it on the charger and went to bed. I got up this morning and now nothing. Not even the bulb lighting up at all. So, I carefully examined the bulb (a WA1185), took it out, and replaced it with a spare that has not seen the light of day since I originally bought it. Nothing. :candle:

I'm now pretty frustrated. My lack of knowledge/skill in this area is just compounding the issue. I'm just that guy that wants to turn the light on and blind the eff out of someone that thinks it's "just a Maglight." I hope you guys can help...Thanks and Happy Holidays.

 

[tebore]

Check each of the cells. Sounds like the pack is dead.

 

[wacbzz]

Remember that little part about my knowledge/skill with this stuff being limited? How do I check each cell? And would the batteries just stop taking a charge if they are not used for a long time? Thanks.

 

[daBear]

Since NiMH are not that expensive try new cells. The problem you describe is caused by the HD shutting down for low voltage to prevent excess discharge of cells. In your case you have at least one bad cell which is causing the shut down. that HD is probably set to 10.8 volts or so and your pack is delivering less than that. Try some really good AA cells capable of a high discharge rate and you will be surprised how much more your Mag85 will deliver.

 

[wacbzz]

Since NiMH are not that expensive try new cells. The problem you describe is caused by the HD shutting down for low voltage to prevent excess discharge of cells. In your case you have at least one bad cell which is causing the shut down. that HD is probably set to 10.8 volts or so and your pack is delivering less than that. Try some really good AA cells capable of a high discharge rate and you will be surprised how much more your Mag85 will deliver.

Any suggestions?

 

[DonShock]

A problem I've had with the FM packs is that the center pin of the charge jack losing contact with the center post of the pack that provides connection to the positive end of the pack. I got very similar symptoms, a quick charge indication as I plugged the charger into the pack, then a loss of contact as I let go. In my case it was getting frequent use, so I think over time as I pulled out the charging jack it pulled slightly on the center pin until the contact became intermediate. I tried several solutions, but the most reliable was also the simplest. I just used a punch to tap in the center pin more firmly to restore reliable contact. It would last a few weeks before needing to be done again. The one caution is make sure not to use a conductive item as a punch since you can easily short the pack if you make contact with both the center pin and the side of the jack at the same time. I picked up some 1/4-20 nylon bolts at the hardware store to use for this and they worked great. Solid enough to take a firm tap, non-conductive, and cheap.

 

[wacbzz]

Ok-I went to Batteries Plus and had them put some new batteries in my light. I charged them up...

Nothing.

WTF?:thinking:

 

[RickB]

Ok-I went to Batteries Plus and had them put some new batteries in my light. I charged them up...

Nothing.

WTF?:thinking:

Do you have a multimeter? These lights are pretty simple circuits (excepting the AWR hotdriver), but there's several spots that can cause "open circuit," and it's a lot easier to track down if you can check actual voltages and continuity/resistance.

-Rick

 

[wacbzz]

Do you have a multimeter? These lights are pretty simple circuits (excepting the AWR hotdriver), but there's several spots that can cause "open circuit," and it's a lot easier to track down if you can check actual voltages and continuity/resistance.

-Rick

Thanks Rick, but unfortunately I do not. Is this something I can take to/have checked at batteries plus?

I know I seem like the completely uneducated user - and I am. I just want that light to work and had hoped the batteries would do it.

I'm getting to the point where I am thinking about parting it out or selling it whole...

 

[daBear]

Sorry to have not replied again earlier. I am having computer problems and am waiting on a new Motherboard from Hong Hong to get back up and running. I am on a borrowed pc right now. I was going to suggest Elite 1700 NiMH cells from Cheap Battery Packs but since you have alrady tried new batts my original suggestion won't apply. Other than realy high discharge batteries will work much better than the Wal-Mart specials.

Don Shock is right on in his post as I have had similar problems. At this point I would invest in an inexpensive digital multi meter which can be had for 10 dollars or so. You will not be able to trouble shoot your problem without one.