Adapter to run a 8.4V DC LED light from 110 VAC power?

stanleyoutdoors

Newly Enlightened
Joined
Feb 10, 2014
Messages
7
Hello,
I have a light that runs on a 8.4 V battery pack (4 18650's) but I would like to be able use it as a worklight in my shop and run it by plugging it into the wall (110 VAC American power). The light CLAIMS it's 45 watts. I have searched for an adapter but the most output I can find is 23 watts at 8.4 VDC.

The light has (5) T6 emitters, similar to this one:
http://www.ebay.com/itm/5-x-XM-L2-T...914607&hash=item4b13fef425:g:j6cAAOSwXYtYz~ZG

Sorry if this is a re-post but I did search and came up empty.

Any help much appreciated!
 
Last edited:

fivemega

Flashlight Enthusiast
Joined
Jan 28, 2003
Messages
5,530
Location
California
A- 45 watt is not even close to reality but if it is, then must consume about 6 Amps. Does it?
B- Make sure your power adapter is voltage regulated and never goes higher than 8.4 volt.
C- Make sure your light can work continues without heat issue even if not in motion.

BTW, there are many 110V LED lights in market which serve you better in different power, dimmable, and less cost.
I hope this helps.
 

snakebite

Flashlight Enthusiast
Joined
Mar 17, 2001
Messages
2,725
Location
dayton oh
there are 2 possibilities for that lamp.
emitters in 5p with buck converter or 5s with boost.
many such drivers would be happy on 12v which is easier to come up with.
for example the power supply from a junk xbox 360.
as mentioned this lamp may depend on airflow from motion to cool it.
this may not even matter as i doubt it drives the leds anywhere near its claim.
voltage limit with buck is determined by voltage rating of mosfets.
and boost cannot exceed vf of the led string.12v would be safe for 5s with boost.
 

stanleyoutdoors

Newly Enlightened
Joined
Feb 10, 2014
Messages
7
Well, there are power supplies able to supply that current/power.
But they can hurt your budget also.

So, please let us know about the budget to give you some clues.

A quick check: https://www.aliexpress.com/item/XIN...er-For-7-4V-Electric-Scooter/32829022882.html


I'm going to try the above power supply and see what happens. My desire is driven by curiosity more than need or thrift, so the budget is OK.

I've tested the light with no air flow and it does fine- gets pretty warm (still Ok to touch) and doesn't seem to degrade.

I did try running a similar light on 12V once and let the smoke out- so no go on that.

Thanks everyone- I'll let you know how it works (or doesn't).
 

Enderman

Enlightened
Joined
Nov 3, 2016
Messages
328
Location
Vancouver, Canada
Go look on mouser or digikey, there are tens of thousands of power bricks there and you can just sort by what specs you want.
 
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