TD;
Some time ago I pontificated on the various types of switch contacts--
ones that were suitable for power and those suitable for low- voltage,
low- current (so-called "dry circuit") applications. Connector pin
contacts are similar.
At very low voltages & low- currents a contact will develop a thin oxide
on its surface that acts as an insulator. Higher voltages & currents can
punch through this oxide and make good contact but for dry circuit
applications such as data logging sensors, etc., a plating of gold on
the pins is necessary to prevent the oxide growth.
Hope this explains the basic problem.
Regards, Neil Tucson, AZ
-----Original Message-----
From: todd [mailto:todd@twinjugs.com]
Sent: Monday, August 02, 2004 9:39 AM
To: Albaugh, Neil; List Land Speed
Subject: RE: Weather-Pack and Deutsch connectors
Paul mentioned to me about the military spec connectors as well as the
gold
pins and sockets(and if I ever have a failure with one of these may
consider
going to those). I have done some heavy vibration, pull strength and
under
water testing with these standard connectors and feel very comfortable
with
them for our applications, I use the solid pins(a bit more costly)
rather
then the stamped and formed pins though. I plan on stocking the mini
series
now as well. I wasn't aware that the draw had an effect on the ability
or
continuity of the pins themselves though(with everything being clean)..
care
to expand on the reasoning or likelyhood of failure? Excellent info
Neil,
thank you.
TD
> TD,
> It's not for nothing that the US military & aerospace industry uses
> Deutsch connectors. Note that there are other manufacturers of
MIL-SPEC
> connectors besides Deutsch; all of them are excellent.
> If you can't afford a failure, use MIL-SPEC connectors. They usually
> have gold-plated connector pins-- not for looks but to insure good
> electrical contact. Ordinary contacts are not good unless there is a
> substantial current flowing through them. "Dry contact" switch
contacts
> and connector pins maintain good, low-resistance connections even
> with very low current flow.
> Regards, Neil Tucson, AZ
|