120vac rectified to 24vdc for lighting?

[TheEquineFencer]

Here's the situation. I have a bunch of 24vdc LED flood lamps, 10 total. They are pretty much new, but about 10 years old now. They were the same as what were used on solar light towers I used to build for the Military years ago. I think they are less than 1.5A

The shop lights are wired through motion sensors that operates a 20A RIB relay that sends power to each light switch for each light fixture. They are split into two banks, six in the front half of the shop, and 7 in the back half.

My T-8s have already started failing again.

What I'm considering trying, this where I need some input, installing a 120v to 24v transformer ahead of the RIB relay operated light switches, then running the power to a full bridge rectifer, then a DC rated switch and out to the lights 24vdc LED lights until I come up with money for another battery bank.

I'd have a maximum of 7 LED lights on each transformer. Will it work and what rated transformer do I need with a little "extra" for some "cushion?"

I'm wondering about wire size too. I guess that'll depend on if I run a wire to each light, or parallel to each light. 18/2 would be nice.

TIA, TEF

 

[mm08822]

If you go this route, forget the full wave bridge and trani. Just go buy a 24vdc power supply. Otherwise, you need to properly fuse the trani, consider heat dissipation/heat sinks, caps to take out the ripple, and a 120/24vac xformer will only give you ~ 21.5vdc, and an enclosure. Then you have line losses..........

Unless you want a science project, I would re-group.

 

[TheEquineFencer]

I'm looking cheap that works. Where can I get a 24vdc power supply cheaper than building one?

I guess I could get a 120v to 28v transformer... Would a Cap really be necessary?

As far as a science project; I'm always up for learning.

 

[TheEquineFencer]

I'm open for more suggestions...

 

[whateg01]

I'm looking cheap that works. Where can I get a 24vdc power supply cheaper than building one?

Hard to justify much effort when you can buy this.

https://a.co/d/bNxKka0

 

[Stuart in MN]

I agree - unless you want to home brew it as a fun project, just buy a 24vdc power supply. You can probably find a used one on eBay for even less than the one in the Amazon link above, or if there's a surplus store in your area see what they have on hand.

 

[rlitman]

I'm looking cheap that works. Where can I get a 24vdc power supply cheaper than building one?...

ANYWHERE! 24VDC LED drivers are way cheaper than what you're conjuring, use less power, and have cleaner output that isn't going to burn out your LEDs prematurely.

 

[mm08822]

I'm looking cheap that works. Where can I get a 24vdc power supply cheaper than building one?

I guess I could get a 120v to 28v transformer... Would a Cap really be necessary?

As far as a science project; I'm always up for learning.

I don't think you could possibly buy everything needed for less than $24 providing anything with long term reliability.

Those lights may also be a misfit for your needs.

Without a smoothing capacitor to take out the ripple of the rectified sine wave, your drivers may not work or have low life.

Google full wave rectifier, ripple (not the juice), and smoothing capacitors. Mountains of info......been done for decades.

Not to be a kill-joy, but just replace the T-8s.

 

[alfredeneuman]

Not to be a kill-joy, but just replace the T-8s

With LED lamps.

 

[walta]

I think if you put any value on your time This 24V 20Amp switch mode power supply will cost less to install, use half the power, be safer with over current shutdown, take up ¼ the space and weigh 90% less. cost 26.99

Amazon.com: 24V 20A Switching Converter, Switching Power Supply, AC/DC Voltage Regulator, AC 110V/220V to DC 24V 20A 480W Transformer Power Adapter Converter for LED Strip, LED Display, 3D Printer : Tools & Home Improvement

Buy 24V 20A Switching Converter, Switching Power Supply, AC/DC Voltage Regulator, AC 110V/220V to DC 24V 20A 480W Transformer Power Adapter Converter for LED Strip, LED Display, 3D Printer: Low Voltage Transformers - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

Walta

 

[TheEquineFencer]

$$$

With LED lamps.

$$$ is the problem. 52 would be needed. I have the LED flood lamps, I know they last.

 

[TheEquineFencer]

Hard to justify much effort when you can buy this.

https://a.co/d/bNxKka0

That might be doable, thanks.

I think if you put any value on your time This 24V 20Amp switch mode power supply will cost less to install, use half the power, be safer with over current shutdown, take up ¼ the space and weigh 90% less. cost 26.99

Amazon.com: 24V 20A Switching Converter, Switching Power Supply, AC/DC Voltage Regulator, AC 110V/220V to DC 24V 20A 480W Transformer Power Adapter Converter for LED Strip, LED Display, 3D Printer : Tools & Home Improvement

Buy 24V 20A Switching Converter, Switching Power Supply, AC/DC Voltage Regulator, AC 110V/220V to DC 24V 20A 480W Transformer Power Adapter Converter for LED Strip, LED Display, 3D Printer: Low Voltage Transformers - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

Walta

Another good choice.

 

[TheEquineFencer]

I agree - unless you want to home brew it as a fun project, just buy a 24vdc power supply. You can probably find a used one on eBay for even less than the one in the Amazon link above, or if there's a surplus store in your area see what they have on hand.

That's not a bad idea to look used/surplus!

 

[cmandp]

How much are you going to spend on wire, switches, hardware to hang those 24v lights? What about your time to wire and hang the new lights?

For less than $400 you can retrofit ALL of your T8 fixtures to LED https://greenlightdepot.com/product...ss-dot-dimming-etl-dlc?variant=40885842739243
I'd probably bypass the ballasts but these technically should work with electronic ballast fixtures.

 

[cmandp]

Is that a "Wow" cheap or "Wow" expensive lol?

 

[TheEquineFencer]

CHEAP!

 

[tfi racing]

Why are your T8's failing? I service stores ( 1000-4000 lamps plus per store) that had Phillips T8 LED lamps and ballasts installed almost a decade ago, and the failure rate has been a surprisingly small percentage and the many of those in the first five years were installer error. You should to be able to get 52 ballast bypass T8 lamps for far, far less than the money and time you're are going to have to invest in this endeavour.

 

[OccupantRJ]

Why are your T8's failing? I service stores ( 1000-4000 lamps plus per store) that had Phillips T8 LED lamps and ballasts installed almost a decade ago, and the failure rate has been a surprisingly small percentage and the many of those in the first five years were installer error. You should to be able to get 52 ballast bypass T8 lamps for far, far less than the money and time you're are going to have to invest in this endeavour.

@tfi racing, Is there a particular type B lamp you would suggest with your experiences for a home workshop With a 9 foot ceiling?