DC lighting?

ligwyd

Anyone know where to get high quality DC lighting products? I am looking to run a motion sensor light directly off my 48v battery bank without the main inverter having to be on. I don't like the idea of having to leave the inverter on and consuming 28 watts just to turn on a 30 watt LED motion sensor flood light.

Ampster

ligwyd said:

Anyone know where to get high quality DC lighting products?

I checked our host's store and didn't find anything.

Here is the first thing that came up on a google search. 
https://www.alibaba.com/showroom/48v-motion-sensor.html
Amazon has some 24v sensors. 

BB.

I probably would use a DC to DC buck converter and use "standard" 24 or 12 VDC lights and detectors...

Size the converter to your loads (just like AC inverters, these will have some sort of current draw when just on and no loads). For example, here is a good size DC to DC buck converter with ~12 amp output (at 12, 24, or variable):

https://www.amazon.com/Converter-DROK-Voltage-Regulator-10V-75V/dp/B071LGTTRN
https://images-na.ssl-images-amazon.com/images/I/B1PU4fR9DiS.pdf

94% efficient (could not find Tare draw)...

-Bill

Estragon

Depending on climate, and length of wire run from batteries to light location, it may also be worth considering a standalone light/panel/battery combination.

FWIW, my experience with integrated PIR/light packages hasn't been great (not able to aim & adjust to get the light to only come on when wanted).  That may be partly my climate though, as the problems seem worse in winter.

ligwyd

I wonder how hard it would be to introduce some capacitors (or whatever would be the proper electronic components and terminology) into an existing 120 VAC motion sensor fixture so that the search mode pulses could be stored that would enable the motion sensor circuitry to operate properly and call for full power when tripped by motion?

In my particular situation, I only need 30 watts LED max 120 vac to power a LED light that would give me satisfactory light so thats only .25 amps at 120 v. or 1.25 amps with 24 Volts. I would hope the small draw from the converter would be less than the 28 watts from the inverter being on all the time

Thoughts on this little guy?

https://www.amazon.com/Waterproof-DC-Converter-Transformer-Regulator/dp/B07MXGW7ZJ/ref=sr_1_6?ie=UTF8&qid=1548719820&sr=8-6&keywords=DC+Buck+Converter+48VDC+step+down+to+24VDC+2+amp

Also, anyone no of decent quality, hopefully somewhat mass produced 24 volt dc light and motion sensors? I'll search the RV market and the internet but do appreciate any suggestions.

Horsefly

I second Bill's suggestion on the buck converter. 

We have a 24V system, and I put in a few 12VDC lights and motion sensors for night lights in the upstairs and downstairs hallways and the bathroom. That way we can (if needed) shut down the inverter during the night.  I'd have to go look at what specific ones I got, but I know I found most of the stuff I used on some boating and RV sites. I know I looked first for 24VDC lights, but there were way fewer choices and they were much more expensive than the 12VDC lights.

I just checked and the buck converter I got was this one: https://www.amazon.com/Pyle-PSWNV720-Power-Converter-Technology/dp/B003P17X8I  It's been working fine for a bit over a year.

Estragon

I'm not sure what the little guy actually is.  The heading suggests 24v output, but the text seems to say 13.8v.  Not sure what 1/2/3a means, or if 48v input is a max input voltage (48v nominal bank could be 60+v in operation).  12v nominal lights would certainly be easier to find, and likely cheaper.

In theory, I suppose capacitor(s) & related circuit(s,) might be able to use pulse current to run a PIR detector, and when tripped, bring an inverter out of search mode.  Might be kinda fun, but not trivial as a first project.