I bought a Mean Well XLG-150-24-A power supply. It provides 6.25 A at 24V. I want to place it somewhere in the middle of my flat (in a kind of server room) and set up a centralized 24V distribution system throughout the flat—for some LED strips and a few low-power devices.

Is it possible to determine what cable I need for this setup? Can I use 1.5 mm² cable, or is it better to go with 2.5 mm²?
I also noticed that there are speaker cables with the same cross-section, as well as special 12/24V cables with better insulation.

Can you advise me on this?

Thanks!

 

you can use 1.5mm^2 (AWG18 in North America), since it is rated for more than double of what your PSU output current is. using larger wire allows for lower voltage drop at same current.

there are calculators for this, such as
https://www.grealpha.com/resources/dc-load-wiring-calculator/calc/voltage-drop/

if you enter AWG 18, wire length (one way) of 30ft, and expected current (6A) you will see that voltage drop is significant (about 10%).

if this is a problem for your load, you will need to use either larger size wire or shorter cable or both. also do not daisy chain loads, specially if they draw a lot of current, better use separate wires for each load (from PSU to load).

 

I have seen flat cables marketed specifically for under carpet installation. I do not recommend ever running power wiring or speaker wiring under carpets, if that was what you are thinking. The big issue is the voltage drop when you draw power through the wires. That is mentioned in post #2 and it can certainly be a problem with voltage drop. Probably the effect on LED lights will be less than the effect on other electronic items. So it may make more sense to put the supply closer to where most of the loads are located.

 

I would recommend fuses on each separate load. That way, if you get a short on one LED Strip, you can find it immediately, and it lets the others continue to operate instead of shutting down the power supply.
Also, if at some point in the future you add a 24V battery, you don’t create a fire hazard.

 

thank you!

@Ian0 what fuse is on your mind? for each separate branch going from 24V circuit?

@MisterBill2 want to install in ceiling / or in the skirting boards

@panic mode thanks, yes the voltage drop is also on my mind. So i can say from the central point i will need branches each around 20m long

I am still wondering how they design such a distrubution system in case "end point devices" are not specified.
And also one day u can change the end point devices, so i believe the distribution system ie cables shouldnt be dependent on the endpoint devices? so confused.

thanks!

 

thank you!
@Ian0 what fuse is on your mind? for each separate branch going from 24V circuit?

thanks!

Yes.

 

I have a low voltage system in my house.

I use 14-gauge cable out to local distribution points, where I then use the proper cable for each device.

I have a main fuse at the supply and fuse on each local distribution point.

I also have a capacitor at each distribution point...but that is optional.

 

I have a low voltage system in my house.

I use 14-gauge cable out to local distribution points, where I then use the proper cable for each device.

I have a main fuse at the supply and fuse on each local distribution point.

I also have a capacitor at each distribution point...but that is optional.

@ElectricSpidey thanks

What max distance of cable do you run from main point to the local distribution points? And what type of cable? Do you install it into the pipes inside the walls?

Do you run 24V?
Could you recco specific fuse?
For a what reason do u use capacitors there?

thanks

 

I like the 10x38mm fuses because you can get 17.5mm wide DIN rail fuseholders that fit a standard distribution board, the same size as an MCB.

 

@ElectricSpidey thanks
What max distance of cable do you run from main point to the local distribution points? And what type of cable? Do you install it into the pipes inside the walls?
Do you run 24V?
Could you recco specific fuse?
For a what reason do u use capacitors there?

About 25' or so.
Standard low voltage cable with sheath.
No pipes.
It's 12-volt 20 Amp switcher.
I just use standard low voltage AGC fuses.
The capacitor helps reduce the flicker on some LED fixtures I have installed.

 

so basically u firstly designed where you need to place endpoints and based on that you have designed local distribution points?

Also do you use some specific wall sockets? thanks

 

Yea I designed this system many years ago and tried to make it as modular as possible, but you know what happens over time...

I have used several different terminal points over the years, everything from RCA jacks to barrier strips and euro style terminals strips.

 

It seems odd that the world has never evolved a de facto standard for low voltage medium current applications.
Something between the 2.5mm barrel jack and the Anderson connector.
Wheelchair and golfbuggy people like 3-pin XLRs much to the consternation of anyone with a microphone.
Speakons would be good so long as there are no loudspeakers in the vicinity.

 

i am still not sure how to approach it ... i mean i dont know where i place endpoint devices, but i want to finalize electrical network... so no clue.

 

Quite often, electrical sub-distribution points are located conveniently close to the points of use. That is similar to the scheme used to locate mains power outlets.

As for "standard DC connectors", there are MANY of them, lots of "standards". ( that is supposed to be a funny comment, folks.)

 

@MisterBill2 seems one has to completely design Interior and placement of devices... before flat reconstruction and new outlets placement ;/

 

Probably not "Completely Design," but decide which locations will have 24 volt devices and which will have mains powered devices. That is no different than has been done to some extent for homes, and to a much greater extent for offices and other specialized activity construction for many years. Planning in advance certainly does require additional effort, but often it allows for convenient installation and moving in later. Itmight even save you a fair amount of money, especially if you provide 24 volt power for lighting early in.

 

Anderson Powerpoles might be a good choice. Their use is widespread for DC power systems and an number of different in-wall mounting holders can be purchased or 3D printed.

They are also hermaphroditic, meaning any connector can plug together – they aren't male and female. Extension cables will plug in no matter which way they are run

 

Anderson Powerpoles Are indeed quite good connectors, and they are quite rugged, compared to several other types. An added advantage is that they can be soldered on instead of being crimped permanently. The benefits of a soldered connection are that it does not require an expensive crimp tool, and that it can be corrected if it is not perfect the first time. In addition, soldered connection pins can be used a second and third time, while a crimp is permanent and not re-usable.

 

Anderson Powerpoles might be a good choice. Their use is widespread for DC power systems and an number of different in-wall mounting holders can be purchased or 3D printed.

@Jon Chandler
its insane to find something usable for a brick wall.