Current rating on Multipin Connectors

[home_listening]

Hi,

I'm currently building a sidecar and require a cable + connector to transmit 5 DC voltages plus ground from the external power supply to the console itself. I'm looking for it to handle up to 5A in both +ve and -ve 18V, 1.5A in both +ve and -ve 22V and enough +48V for 8 channels. I'm keeping a close eye on the current ratings of the connectors and have more or less decided on using the Amphenol MS series (MS3102A18-8P more specifically) which are rated to 13A/700V.

However, I have no idea whether this is per pin or a total rating for the connector.

Any help would be greatly appreciated, Thanks.

 

[gridcurrent]

The 5 pin EP (formerly P) series connector is rated at 20A per pin.

 

[sodderboy]

I like these TE Connectivity connectors because of the mix of large and small pins.  Formerly CPC connectors.  The large pins have a very high current rating.  I would look for at least double what you need for longevity.
Mike

 

[home_listening]

Hi,

Thanks for the help with this ;D ;D, I had seen the Amphenol EP series before but those TE connectors are new to me.

So to confirm, to complete the whole connector I would need :

-Shield
-Jack
-Panel Connector
-Crimp Pins

Since I've got your attention , Do you have any recommendations for a suitable multicore for this? I'm now thinking that the cheapest and simplest solution is to just run all of the connections down 16AWG stranded wire put through some heatshrink to keep them neat and tidy. Would love to hear some feedback on that idea.

Thanks again, and in advance.

 

[sodderboy]

Shrink is too stiff when finished, so go with Techflex.  You can put what you wish inside and it will not be stiff.  Different sizes should be available wherever you are.  When I do what you are doing, I will twist the +, - of each voltage together, have the 0vl wire alone, and twist the lesser gauge phantom wires together.  The twist trick is to cut length to 125% of necessary length, tie the wires together at one end, stretch and tie at the other, put one end in a vise or an anchored hook, put the other in a hook on a drill, and slowly twist them to desired tightness.  The drill hook will equalize the two lengths when you start.
And since it is a "sidecar", maybe you should put the engine (PSU) inside the unit.  The shorter the PSU connection the better.
Mike

 

[home_listening]

Great, thanks for the heads up on the techflex.

And since it is a "sidecar", maybe you should put the engine (PSU) inside the unit.

I'm now thinking this is going to be the best idea as well, the cost of connectors and cable running between an external PSY + a 19" rackmount case easily double the cost of the PSU. I guess I'll just place all of the transformers inside a big hammond case or something similar to reduce noise.

Thanks again.

 

[rkondner]

Hi,
  Actually you might be better off with a simple 25 pin D! Let me say why.

  The actual metal to metal contact of a metal surface is defined by pressure and the actual contacting area is very tiny. A small pin has no advantage over a large pin in this respect. However a large pin will have lower IR drops and it will conduct away heat better.

Putting a number of smaller contacts in parallel is better than trying to use a single BIG connector pin. Individual wire lenths used for each pin will help even out currents. And multiple pins mean heat is removed via multiple paths. Use 3 pins will drop each pin current to 1/3. So IR heating is down 1/9. Thats big deal.

A standard "D" connector pin is rated for 2 or 3 amps and the solder up version are very easy to solder with wires. And for you 5 V circuit it will probably be IR drops that hurt. You can parallel as many wires / pin required to get the required minimal drop. You might be able to get #20 wire into a solder cup.

Bob K.