Matronics Email Lists :: View topic - max current through sub-d pins

Matronics Email Lists
Web Forum Interface to the Matronics Email Lists

Get Email Distribution Too! FAQ Search Memberlist Usergroups Register

Profile Log in to check your private messages Log in

max current through sub-d pins

Matronics Email Lists Forum Index -> AeroElectric-List

View previous topic :: View next topic

Author Message

hotwheels

Joined: 01 Jun 2007
Posts: 240

Posted: Sat Jul 23, 2011 7:11 pm Post subject: max current through sub-d pins

I know I've seen this somewhere in the past... Can anyone point me to a doc that describes the max current allowed through a single sub-d pin? 



Thanks!

Jay

Exiting RV-10 door purgatory...

- The Matronics AeroElectric-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?AeroElectric-List

enginerdy(at)gmail.com
Guest

Posted: Sat Jul 23, 2011 7:48 pm Post subject: max current through sub-d pins

This Amphenol one is rated to 7.5A.

http://www.alliedelec.com/search/productdetail.aspx?SKU=7203030



These Tyco parts range from 3A to 7.5A (pdf page 4)

http://www.te.com/commerce/DocumentDelivery/DDEController?Action=showdoc&DocId=Catalog+Section%7F82068_AMPLIMITE_Right-Angle_Posted_Conn%7F0108%7Fpdf%7FEnglish%7FENG_CS_82068_AMPLIMITE_Right-Angle_Posted_Conn_0108.pdf%7F1-1393480-7

Best to check your specific part data sheet.

On Jul 23, 2011, at 10:11 PM, jayb wrote:



 	  Quote: 	
		   

 

 I know I've seen this somewhere in the past... Can anyone point me to a doc that describes the max current allowed through a single sub-d pin? 

 

 Thanks!

 Jay

 Exiting RV-10 door purgatory...

 

 

 

 

 Read this topic online here:

 

 http://forums.matronics.com/viewtopic.php?p=347512#347512

- The Matronics AeroElectric-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?AeroElectric-List

nuckolls.bob(at)aeroelect
Guest

Posted: Sun Jul 24, 2011 6:00 am Post subject: max current through sub-d pins

At 10:11 PM 7/23/2011, you wrote:

  	  Quote: 	
		  --> AeroElectric-List message posted by: "jayb" <jaybrinkmeyer(at)yahoo.com>



 I know I've seen this somewhere in the past... Can anyone point me to a doc that describes the max current allowed through a single sub-d pin? 	


   A single 20AWG machined d-sub pin in relatively

   benign environments (not hot) is good for 7A.

   How much are you wanting to run? Is it continuos

   or intermittent duty? If you need a LOT of current

   capability through a harness terminated with a d-sub,

   you can parallel pins. Check out these conversations on the

   List some years ago.



  http://tinyurl.com/3wldv5g 



 

  	  Quote: 	
		     Also this excerpt from another conversation.



      >I could use some simple guidance here

- assuming one correctly applied pin 

      >on both sides of the connector, how

much current can I safely pass through 

      >one of them before needing to split

the power connection between two 

      >pins?  or Three?  or Four?

      

        For the target project, I

derated D-sub pins to 4A. For larger

        current requirements, I

parallel whatever is necessary to keep

        individual pin loading to 4A

or less. To parallel two pins,

        you need to swamp out the

small variation in resistance from

        pin to pin.  It's seldom

satisfactory, for example, to simply

        short an array of pins

together at the back of the connector

        and expect current through the

array to distribute evenly

        across the array.

      

        Taking a cue from past tasks

where I needed to parallel multiple

        transistors in a power control

circuit (we added small value ballast

        resistors in series with the

emitter lead of each transistor) I

        reasoned that we can short all

the pins together at the connector

        on one half (in this case the

etched circuit board side). For

        the mating connector, each pin

gets a 22AWG wire about 10"

        long. The array of wires is

joined to a common butt-splice.

        The other side of the butt

splice carries on with the size

        of wire appropriate for the

circuit's total current.

      

        The approximately 10 milliohms

of wire resistance offered by

        each pigtail has the same

effect as the ballast resistors

        in an array of paralleled

transistors. Tiny variations in

        resistance from pin-to-pin a

insignificant compared to the

        value of the ballast

resistance.



        See:

[/b] 	
 http://tinyurl.com/3flxqcc 



  	  Quote: 	
		          Here I suggested a 3A

de-rating but I believe we were

        talking about stuff that was

tested hot . . . like

        80C. I think I derated those

target pins to 2A. I seem

        to recall 7 pins in the 20A

array of pins. These are

        continuos duty considerations

too. The pin can carry

        intermittent currents on the

order of 2x the continuous

        rating.

      

      

      >  Why not keep power on 

good ole AMP/Molex 

      >connectors?

      

        The D-sub connector is

compact. You can get very high

        quality gold plated pins for

them. They're easily worked

        with low cost tools . . . even

if you use the machined

        pins.  The AMP

Mate-n-Lock and Molex connectors don't

        come in right angle PC mount

versions. Their contact

        density is much lower than the

D-sub. I don't think you

        can get them in greater

numbers than 12 contacts per

        plug/socket.

      

        If you're building a product

where you'd like to mix

        high current (10A+) wires in

with small signal wires,

        the AMP/MOLEX solutions will

either have you paralleling

        conductors in the small pins

-OR- having to upsize the

        connector just because you

have one or two wires out

        of the total that carry heavy

current.

      

        The D-sub solution offers a

fair selection of connector

        sizes (9, 15, 25, 37, 50) and

a large range of connector

        configurations that let you

deal seamlessly with

        panel mount, ecb mount and

cable mounted versions.

        You can easily intermix

micro-amp signal and control

        with some rather hefty power

wiring with a single

        technology.

      

        There are some new circular

connectors from AMP that

        use the same pins as the D-sub

. . . these too might

        be considered for similar

treatment . . . I'm not

        sure if AMP offers any ECB

mount versions yet . . . and

        it's unlikely that there will

ever be a right-angle

        ECB version.

      

        All things considered, in

spite of the ugly hole you

        have to cut to mount a D-sub,

the availability of

        low cost, high quality pins

and inexpensive tooling

        combine to make them

attractive for a broad

        range of applications.



[/b] 	


   Bob . . .    [quote][b]

- The Matronics AeroElectric-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?AeroElectric-List

hotwheels

Joined: 01 Jun 2007
Posts: 240

Posted: Sun Jul 24, 2011 12:13 pm Post subject: Re: max current through sub-d pins

Nothing fancy here... Just using D-Subs provided by Stein. I don't recall ever seeing a datasheet on those parts. 



Regards,

Jay

- The Matronics AeroElectric-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?AeroElectric-List

Display posts from previous:

	Matronics Email Lists Forum Index -> AeroElectric-List	All times are GMT - 8 Hours
Page 1 of 1

Jump to:

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum