How many Lumens is my kpr139 putting out

[Mike Iver]

I am running a pt 40 with a kpr139 on 4 NIMHs. I was wondering if anyone knows how bright this light is? I just want to know to be able to compare it to some new lights that I am thinking of purchasing. Thanks

 

[Mike Iver]

Any wild guesses? I know that I am not the only one using this combo. In fact, this is where I heard of it. I would have to guess 60 - 100?

 

[AZLight]

I am running a pt 40 with a kpr139 on 4 NIMHs. I was wondering if anyone knows how bright this light is? I just want to know to be able to compare it to some new lights that I am thinking of purchasing. Thanks

It is a lot brighter than my HDS U60 so I would put it at least 100 lumens.

 

[Handlobraesing]

It actually depends, actually, a total function of the voltage the lamp is getting under operation.

 

[adirondackdestroyer]

I have this same setup and I would think it is at least 90-100. I say this because I had a modded G2 with a 100 lumen bulb and these two lights were very similar if overall output, with the KPR139 being a little bit brighter.

 

[Paul5M]

1. Measure the current flows through your bulb.
2. Compare the measured current to 6V (2x CR123) lamps here.
3. Locate a flashlight that uses this lamp, from step 2, here. That's your estimated lamp's output (+/-10%) :thinking:
Good luck

 

[Mike Iver]

Thanks

 

[LEDAdd1ct]

I couldn't find a definitive answer to this either, so I looked and looked, and finally found this handy dandy table here:

Link

According to the link, KPR139 specs are:

3.85 volts

1.32 Amps

75.4 lumens



Question answered!

LEDAdd1ct

 

[NightKids]

Good stuff LEDAdd1ct !

 

[ericjohn]

Now you got me curious; I never heard of a KPR139. I am guessing that is a Krypton, flange or screw base bulb. Typically what batteries is it designed for? I made a list of all the PR bulbs I had known of, recently, and in my research I never came across that number of bulb. When it comes to flashlights I am always willing to learn so enlighten me, pun intended.

 

[LEDAdd1ct]

Did you do a search on it? There's lots of info both on Google and CPF. In fact, the only information I could not find on it was the exact amount of lumens it was spec'ed for at its rated voltage and current.

 

[Sci Fii]

I'll add a little info on this bulb. I actually found an electronics store that had a bunch of old stuff and had some of these. I picked up 5 of them. Stamped GE and made in the USA so they're old. There's a lot of good info on this bulb in this forum so I'd first start there. One thing you'll see is that many users liked this bulb because it is able to handle four NiMH rechargeable batteries in the popular 4AA lights without worries of instaflashing. I can not only confirm that's true but add that it can take a good bit more voltage. I have run these using 4NiZN batteries up to about 7.2 volts. I have actually instaflashed two. One was when I tried 4 NiZN batteries hot off the charger. About 7.6 volts and no go. Can't remember the other tiem but I believe I had to convince myself again. Still, it really can handle relatively high voltage. The bulb really is quite bright at higher voltages. Well above the lumens at spec. I would guess close to 200 using NiZN. The beam isn't great on the ones I have as it's got a strange filament. Still, it's not bad. It's a thicker beam rather than a thrower and less white that xenon. I'm getting some AA LifePO4 batteries in soon and will be trying this bulb with them. Two of those will yield about 6.0 volts. This could be a great bulb for that set-up.

 

[dlrflyer]

That's the thing, most are using this on 4 AA NiMH batteries, so the lumen amount is much higher, probably closer to 110 lumens or more with that much overdrive.