Re: [SI-LIST] : Contact Current Rating ?

Dennis Tomlinson (det@tellabs.com)
Fri, 22 May 1998 08:50:44 -0500

WonSae Sim wrote:

> Hello, SI Experts
>
> I,m concerning how much power pin have to be assigned to meet the power
> requirement of a card. "Contact current rating" of the catalog of a
> connector is the only clue for me to decide the number of power pin in
> the connector.
>
> Assume the power requirement of the card is 50 watts, supply voltage 5
> volts and the contact current rating 1 A. Then 10 power pin pairs (VCC,
> GND) are enough?
>
> Could anyone tell me the meaning of "Contact Current Rating" and how to
> meet power requirement of the card?
>
> Thanks in advance
>
> --
> WonSae Sim
> Senior Engineer
> Computer Division, ETRI
> 161 Gajong-Dong Yusong-Gu, Teajon, 305-350, R.O.KOREA
> +82-42-860-4827 (V), +82-42-860-6645 (Fax)
>

Greetings,

I didn't have a good definition for you, but having the internet at my
disposal, I searched on "contact current rating" and found:
1. A vendor who defines it as a "test condition",
2. Another vendor who defines it as a max DC current,
3. Another vendor who defines it as the current required to
cause a 20 mV drop,
4. Another vendor who defines it as a "nominal condition", and
5. Another who defines it as the current required to
cause a 3 mV DC drop.
Most vendors give both AC and DC ratings, with the DC
being by far the lower. Some don't mention AC or DC.