Need help with explaining forward current

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pswii60
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Need help with explaining forward current

Hi guys I’m new here and recently got into this as a hobby.
I have an old spotlight from Canadian Tire that I want to upgrade with an xm-l2 that I have lying around. The spotlight uses xb-d emitter and I’ve been checking out the spec sheets on both xb-d and xm-l2, the only discernible difference that I can see is that the forward currents on both emitter are different with the xb-d working with 1000mA and the xm-l2 having 3000mA.

Can I just slap the xm-l2 onto the spotlight and be good to go?
Or would I have boost the current somehow?

ChiggerPepi
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This figure is essentially the maximum power each is rated for by the manufacturer. Assuming the driver in your spotlight has some sort of current limiting ability to prevent the existing LED from self-destruction, it will liekly be already limiting the current to 1000mA or less, to protect the XB-D from self destruction and overheating. This means an XM-L2 will be a drop in replacement no issue, but the caveat is that it will not be operating at full potential, as it will be limited in power (and brightness) to whatever the driver will give, which we are already assuming is 1000mA or less. This is a safe exchange, but you may not gain much (if any) light. For more power, you would also need to change/modify the existing driver, which will then also possibly present additional issues. If you beef up the driver, you now are generating a lot more heat, which will likely not have been accounted for by the original designers when they built the light. It’s a can of worms, but… that’s what some of us love to do, open cans of worms and make things better/brighter, and potentially less safe, but more fun.

Short answer:
You can install it no issue, but might not be brighter like you are hoping.

ChiggerPepi
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Oh, and welcome to the forum!

pswii60
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Thank you, ideally I’d like the emitter to be pushing somewhere around double the current of the previous emitter. I checked the output and death test put out by Texas_Ace for the xm-l2 and 2 amps puts me somewhere in the ballpark of ~700 lumens. The only bottleneck that I have is the housing of the spotlight as it’s a copper star sandwiched between a metal heatsink and plastic reflector. My worst case scenario would be the plastic melting from the emitter. How do you think plastic would fare against an xm-l2 pushed at 2 amps?

Zappaman
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Uhm… I’d toss the light (plastic reflector is a big NO), and start over with something from like Sofirn (for say $15 shipped from China) with everything you’d be looking at getting out of this light- BUT with good “everything”: polished aluminum reflector, a driver that runs it at the upper realm of it’s potential, a modern LED, and oh yah… REALLY good craftsmanship!

I get you might be attached to the light though… but just saying you’re probably going to spend more (and spin you wheels) on retrofitting this light Vs. cutting bait and getting a GREAT light for pretty cheap. Sofirn is just one of MANY in that range, and once you “go there” you won’t look back.

ZappaMan

pswii60
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Oh I understand plastic is not a good material by any stretch of the imagination for the reflector but this light is more of a boredom project if anything (ie. if it melts it melts, it if doesn’t then even better). I just bought an Astrolux FT03 and built a Convoy S2+ with parts from Mountain Electronics recently and I’m not planning to buy anything else until my next paycheck.

Ideally I’m looking to find the upper limit of the amount of current that I can run on the emitter before any of the plastic starts to burn.

Zappaman
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Hum…

I guess a new driver might help you get there, as as it has been said… you probably won’t get more out of the existing driver regardless of the led upgrade. But if you got the time (and the emitter) handy you can try and see what you get. I once spent a rainy day replacing an emitter in an older “cheapy” 18650 (and I shaved it for more throw). Basically, it was all for not. But I enjoyed the process and I felt like I somehow improved it (but not really). Never really know until you try though. Wink

ZappaMan

power911
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isn’t xbd a tiny 3535 form factor? xml2 is a 5050. I rather not shave my plastic reflector if I’m doing any mods.

I rather use a domed xpl for a 1 on 1 replacement for less focusing donut issues. Plus its quite effective so even if you’re running 1 amp it’s quite noticeable brightness.

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Zappaman
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power911 wrote:
isn’t xbd a tiny 3535 form factor? xml2 is a 5050. I rather not shave my plastic reflector if I’m doing any mods.

I rather use a domed xpl for a 1 on 1 replacement for less focusing donut issues. Plus its quite effective so even if you’re running 1 amp it’s quite noticeable brightness.

There U go! If you got a spare XPL in the box- go for it!

ZappaMan

Microa
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The XBD is 2525 form factor. A little bite smaller than XPL.

pswii60
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I just got into the hobby so I’m working with what I currently have. The form factor of the emitter is a non-issue for me because the reflector isn’t a snug fit and the hole is big enough to fit my pinky finger through.
Just how noticeable would the donut be from jumping to a 5050 emitter?