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I have leds running for around 600 Watts of 5V leds (120 amps). The source of the power are three 48V to 5V converters which each can handle 200 watts.

If I would run this amount of Amps over my PCB I would need a 110mm wide track to carry all the load. The complete location for it on my PCB is only around 100mm. Can I just use 2 planes to connect everything together or should I worry about a short circuit?

current solution: Made the converters not parallel and made them connect with 1/3 of the connectors so that the amps would fall to 40. In this way the track could be much less wide but of course I need to count leds so I do not put to much power on one converter.

Datasheet 48V To 5V DC DC Converter: Scroll down to CHS300

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  • \$\begingroup\$ You could also use a thicker copper layer, or solder on a wire on top of the track? \$\endgroup\$ – Tyler Aug 20 '19 at 15:06
  • \$\begingroup\$ @Tyler thicker copper wire is no option. I'm also trying not to put extra solder on. This would be too time consuming. \$\endgroup\$ – Roel Aug 20 '19 at 15:09
  • \$\begingroup\$ @Tyler Looking back into thicker copper \$\endgroup\$ – Roel Aug 20 '19 at 15:23
  • \$\begingroup\$ @ThePhoton Added it \$\endgroup\$ – Roel Aug 20 '19 at 19:29
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If I would run this amount of Amps over my PCB I would need a 110mm wide track to carry all the load. The complete location for it on my PCB is only around 100mm. Can I just use 2 planes to connect everything together or should I worry about a short circuit?

If you were to locate all the supplies in the same place and fan out all the LED's from the same three supplies, then yes you would need roughly a 110mm track.

It might be better to split the supplies and LED's so they are not running on the same circuit, then that would only be 40A to 200W of LED's that would make the track size smaller and more manageable.

If you put the power supply in the middle of the LED's then you could cut the current in half and reduce the trace size further. Like this:

enter image description here

Then the trace size would be a more manageable 18mm.

Keep in mind that trace sizes vary with temperature rise and copper weight. For example:

A 1oz 12.5mm trace with a 10C rise over ambient temperature can support roughly 14A

A 1oz 12.5mm trace with a 20C rise over ambient temperature can support roughly 20A

A 2oz 12.5mm trace with a 10C rise over ambient temperature can support roughly 20A

A 2oz 12.5mm trace with a 20C rise over ambient temperature can support roughly 32A

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  • \$\begingroup\$ Actually separating the lines around the power supply is an option after reviewing. Thanks good help. Also I am gonna try to convince to increase the copper weight. It has a too big influence. \$\endgroup\$ – Roel Aug 20 '19 at 19:31
  • \$\begingroup\$ meta.stackexchange.com/questions/126180/… \$\endgroup\$ – Voltage Spike Aug 20 '19 at 19:32
  • \$\begingroup\$ If I would place my LED's around the power supply instead of on one side. Could I also just use a plane instead of using tracks? It would look more streamlined. \$\endgroup\$ – Roel Aug 26 '19 at 16:38
  • \$\begingroup\$ Yes, a plane is fine, and better for thermal reasons. \$\endgroup\$ – Voltage Spike Aug 26 '19 at 16:46

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