Power PCB EDge connectors

Discussion in 'The Projects Forum' started by nztech, Mar 10, 2009.

1. nztech Thread Starter Active Member

Feb 24, 2009
44
0
Hi all,

Any one ever had to mount high current connectors to a PCB?
I am wanting to supply/drive a motor from the PCB and wondering if anyone had any ideas re connector for this purpose?

Basically operating at 12V @ 50Amps max
This is rather alot of current. I expect the connectors are going to be rather expensive.
Any ideas and options on how to do this economically would be helpful.

Regards
Blair

2. thingmaker3 Retired Moderator

May 16, 2005
5,072
6
If your PCB traces are quarter inch wide, you'll still be able to boil water with them. Just screw the conductors to the trace with a nut on the other side. And use a BIG fan!

3. thatoneguy AAC Fanatic!

Feb 19, 2009
6,357
718
High End 3D Video cards ran into the same problem. The maximum draw allowed by any PCI card is 1A @ 12V. To power the video cards, there is an extra 6 pin power plug to connect directly to the card's power supply from an isolated rail on from the system power supply.

Right now, 36A/12V bus is the 'official' limit due to UL and safety rules. Although that breaks their prior rules as well...

The ThermalTake 1200W Is the largest PC Power supply made as of this post, here are the outputs:
+5V@30A, +3.3V@30A, +12V1@20A, +12V2@20A, +12V3@36A, +12V4@36A, -12V@0.8A, +5VSB@3.5A.
Cost - \$350

There is another one that "breaks the rules", and offers the following:
Output: +5V @ 30A
+12V@ 100A (115A peak) Single Rail
-12V @ 0.8A
+3.3V @ 24A
+5VSB @ 4A
Continuous = 1200W
Peak = 1400W
Cost - \$549

A beefy supply, using 8 gauge wire, and very thick tracks on the PCB, with thermal fuses on top, is the only continuous duty method.

You could use connectors that are plugged into electric forklifts for charging.

So, no, not really any edge connectors, unless you count 1" wide, 1/8" thick blades going into sockets the same size as "Edge Connector"

Last edited: Mar 11, 2009
4. nztech Thread Starter Active Member

Feb 24, 2009
44
0
Thanks for that.
Is a fair challenge I agree.
I am using mostfet d2pak rating at about 130Amps.

5. thatoneguy AAC Fanatic!

Feb 19, 2009
6,357
718
An eight position molex connector with 10 gauge wire, 4 positive, 4 negative, would handle 50A continuous. Using two 4 position 2x12V connectors that power the CPU power supply. 12ga stranded has a recommended max of 26A, so four in parallel should handle a continuous 50A draw without adverse effects, assuming runs shorter than 2 feet.

The high power section should be made from 2 oz copper with thick tracks, 50A suggests ground plane size tracks. An option for thinner copper would be to use "PCB Power Bus Strips", similar to These