New to BLF, but have been collecting lights for a few years. I’ve decided I’d like to build a desk lamp with anduril, and the dual channel M44 has all the features I’d like for this project. Assuming I can safely strip the mcpcb, driver, and switch from the host, what do I need to plug the assembly into a wall outlet? I’m assuming a USB-C power supply would be the way to go, but what specifically do I need to make that work?
I appreciate any advice on this.
Welcome!
Hi and welcome to the community!
I think the least destructive way would be to machine/ 3D print a decoy battery tube that could make contact with both the outer and inner contact. Serendipitously the M44 has a 3S configuration of cells so it will likely happily run off 12VDC stabilised, that could be obtained from a suitably sized PD charger using a PD negotiation board. The M44 is a powerful light so the power supply would need to be pretty big and i think PD current limit is 3A so you’d only get <36W out of a PD charger. A beefy 12VDC adaptor would do though.
Whatever you do, don’t go over 12.6VDC and beware the polarity!
This is pretty much exactly what I was looking for, thank you, I really appreciate it!
Only thing I’d disagree with is using an actual usb supply, especially if you’ll be pulling lots of current.
One of my bug zappers takes a C input, and works great if it’s A-to-C, but runs off the battery and crokes if I use a C-to-C cable. The “got power” LED lights up with both, oddly.
Just go with a decent 12V supply. Wall-wart if you want, or cable+box+cable.
So many things from external disk drives to my Opus all use 12V supplies, so if I see one at a good price, I’ll pick up extras.
In fact, I think I switched using the come-with 3A adapter for a 5A one, for my Opus, just to make sure voltage/current wouldn’t sag.
They just messed up their USB implementation (badly).
Both my router and my wifi access point have been running off PD PSUs for about a year now, one requesting 20V, one 12V. More and more routers, small computers, computer docking stations etc are starting to ditch barrel jacks for PD inputs.
Also, I’d trust a Anker/Ugreen/Aukey/Baseus (Or Lenovo, dell, HP, Samsung, Huawei…) USB-C PD brick a whole lot more than 90%+ of those 12V supplies which rarely have the manufacturer name written on them (exception: they were bundled with a Lenovo/dell/HP/Samsung/Acer/Asus… device).
As long as the fixed 12V PSUs are from AcBel, Delta, FSP, Enhance, CWT, HEC, LiteOn and a couple or other good quality supply manufacturers things are different ofc and they are reliable.
That’s the point, that cheap devices that only want basic budget power will be happy with cheap/dumb chargers and cheap cables. All they care about is 5V input and no smarts behind it.
The zapper issue arose because I swapped the dumb charger with a multi-port “smart” charger.
Feed it from an A socket, and it gets 5V guaranteed at whatever’s the default nowadays (used to be 500mA by spec, but now I think they can push 2A or so no problem and no negotiating required).
A charger with a C socket pretty much requires the smarts behind it, else any C device plugged into it will report it as “broken” if it wants more but can’t get it.
So I would either need a 12vdc power supply from a reputable manufacturer, or a 12v pd negotiation chip and a USB wall brick, correct?
Is there an amperage or wattage I should be aiming for or avoiding? It’s 2x 50w drivers, so try to stay around 100w?
I think the PD spec originally lists up to 5 Amps at 12 volts (60 watts). But I haven’t seen any PD supplies recently that do this. Most of the ones I have, even the 100 watt and over rated ones, only do the 3 amp part of the spec. You also need a chip that will negotiate for the 5 amps… Not common I think.
A good 12 volt supply would be better. But make sure it is really 12 volts regulated. Many of them are more like 13.8 volts or more open circuit.
Sizing,? I think at least a 10 amp rated supply would be required.
I think you’re right, probably be best to find a quality 12vdc supply and just solder a dc barrel receiver into the circuit. Thank you guys for your help!
Wouldn’t a 10a supply be two much for the 50w drivers?
The device will only draw what it needs. Having a supply rated for more current than required does not matter. Except that it is likely that there be less voltage sag in general with a higher rated supply at the higher current draws. You can use a supply rated at 100 amps if you want to without causing any damage. The thing to match properly is the voltage. Voltage that is too high will fry things!
You guys are amazing, thank you so much for taking the time to explain this! Emailing Hank to see if it’s possible to order a disassembled M44 now.
Do keep in mind that if you get a supply that is rated for less current than you need, you will likely get voltage sag and never get the Wattage that you need. Plus the supply will get hot and possibly fail. So a higher rating within your cost constraints is better. Personally if I can afford it and the size and weight works out for the project, I like to add 50% to the rating of the supply over highest draw I expect to see from the device.
Awesome, I’ll try to find something around 150w!
A couple of examples… BTW, I just found the model numbers at this site. Not a recommendation for this vendor:
The last is 120 Watts, but the listing mentions “12V 10A LED Driver”.
Shop around though. These are just examples I found with a quick search. I do have one of the Meanwell supplies that I use for my radios. A 60 amp model. I have had it for a few years and it has been solid.
Yeah, looks like Mean Well is one of the top brands, trying to decide if that 150w supply is too large, or if I should go for the 120w considering I’m probably not going to put a desk lamp into turbo mode, hahaha.
I tend to think the 120 watt unit, or something similar, should be fine. It is also a nicer package. I can’t tell what kind of connectors are on it though. I found a better picture, there are no connectors, just short leads on the input and output.
Yeah, probably wouldn’t need to worry about heat as much either… I’ll probably pull the trigger on the 120w one. Working out details with Hank!
