What kind of connector do I need?

Ask and answer questions, share tips and resources for installing lighting and other electronics in your models.

Moderators: Sparky, Moderators

Post Reply
User avatar
MillenniumFalsehood
Posts: 17033
Joined: Tue Nov 16, 2004 5:23 pm
Location: Wichita, KS, USA
Contact:

What kind of connector do I need?

Post by MillenniumFalsehood »

I need a connector. Specifically, one which I can use to connect two two-wire cables together. I've got a model that will serve as a model for drawing, and it has lights as well. It will mount from five different locations, so I need a way to disconnect the power supply and move it to another location. It also needs to be small, at most about 1/4" wide.

I looked on Digikey for a suitable connector.

There are literally tens of thousands of types to choose from, and I am genuinely overwhelmed.

Can one of you electronics guys point me toward a suitable connector?
If a redhead works at a bakery, does that make him a gingerbread man?

Ponies defeat a Star Trek villain? Give them a Star Wars award ceremony!
Ant
Posts: 521
Joined: Tue Nov 19, 2002 8:02 am
Location: Oxford UK
Contact:

Post by Ant »

You probably want a micro JST type connector like the ones at the top of this page http://www.jst-mfg.com/product/search_e ... =11&page=1

[Edit: Stupid sites with frames!]
Scott Hasty
Posts: 3419
Joined: Fri Jul 12, 2002 4:13 pm
Location: Chesapeake, VA

Post by Scott Hasty »

Dean's connectors are common and can be found at any R/C hobby shop.
I am fearful when I see people substituting fear for reason
User avatar
MillenniumFalsehood
Posts: 17033
Joined: Tue Nov 16, 2004 5:23 pm
Location: Wichita, KS, USA
Contact:

Post by MillenniumFalsehood »

Ant wrote:You probably want a micro JST type connector like the ones at the top of this page http://www.jst-mfg.com/product/search_e ... =11&page=1

[Edit: Stupid sites with frames!]
That looks like exactly the thing I was looking for! Now, if only JST's ordering page would let me use my credit card (I keep getting an Internal Error message).

I looked for the same thing at Digikey and found the female socket, but it has no contacts provided and I can't find the male counterpart.
If a redhead works at a bakery, does that make him a gingerbread man?

Ponies defeat a Star Trek villain? Give them a Star Wars award ceremony!
User avatar
tetsujin
Posts: 2353
Joined: Mon Feb 28, 2005 6:08 pm
Contact:

Re: What kind of connector do I need?

Post by tetsujin »

MillenniumFalsehood wrote:I need a connector. Specifically, one which I can use to connect two two-wire cables together. I've got a model that will serve as a model for drawing, and it has lights as well. It will mount from five different locations, so I need a way to disconnect the power supply and move it to another location. It also needs to be small, at most about 1/4" wide.
I feel your pain with regard to trying to find simple things on Digi-Key or Mouser. I think it's a little easier if you've got one of their catalogs - sometimes it's easier to flip through pages than it is trying to come up with the right combination of search conditions...

I think I found both parts of the JST connectors on Digi-Key: from the front page go to "supplier index", select JST, the first thing you'll see is a list of "product training" media - rather helpfully, the ACH connectors are right on that list, along with a "parts list" - which gets you very nearly all the way to what you need...

The list has some stuff you're not going to be interested in - item codes for large-volume orders, different variations of the same connector, etc. Looking at the data sheet, it looks like you need four items:

The plug contact, SACHP-003G-P0.2 Digi-Key Item
The socket contact, SACH-003G-P0.2 Digi-key Item
The plug housing, ACHTP-02V-S Digi-Key Item
The socket housing, ACHTR-02V-S Digi-Key Item

A grand total, it seems, of $0.61 per connector pair (two male pins, two female pins, one female housing, one male housing)

Alternately, you could do what I usually do when I need small interconnects: I get pin headers and matching sockets. For instance, these items:
40 pin socket header, 2mm pitch
40 pin header, 2mm pitch

Those two items together cost $3.33. The headers are snappable, meaning you can get 20 2-pin connectors out of 'em. The sockets aren't snappable, but you can still cut them up to get 2-pin connectors by sacrificing a pin (or not, if you want to get really creative) - so in practice you'd probably get 13 2-pin sockets from cutting up the 40-pin socket header. Average cost: $0.26 per connector pair.

The more expensive JST connectors aren't without their advantages - higher current rating (2A versus 1A), and the crimp-on style is better suited to in-line mounting than the pins on the headers and sockets... And the connector halves may lock more securely (haven't tried the JST connectors, so I couldn't say...) And the JST connectors are smaller (3.2mm x 1.85mm when viewed head-on, vs. 4mm x 2.4mm, and 6.8mm depth (including pins) vs. 8mm depth (excluding pins)

So far I've mostly used the pin headers, and haven't felt I've needed anything better (and I've been happy to keep the per-connector-pair cost low...) - plus the pin headers give me flexibility in how many contacts I want (without having to plan ahead and order different parts) - which is something that I do use. But those JST connectors do look awfully nice...

(EDIT): I haven't worked with the smaller JST connectors, but apparently when they use the word "locking" to describe their larger connectors, they are serious. The connectors are made to stay put once put together, and it's important, when disconnecting them, to pull them apart by the housings and not by the pins... Sparkfun has a tutorial that may be relevant - though really it just boils down to what I just said...
---GEC (三面図流の初段)
There are no rats.
The skulls eat them.
Sparky
Moderator
Posts: 2404
Joined: Thu Jun 05, 2003 8:28 am
Location: Are we there yet? (Chicago)
Contact:

Post by Sparky »

I have access to the PNI style shown above, if you're interested PM me with a mailing address I can send a few for you to try out.

The primary issues is how easy it will be to pull them apart without stressing the wires. For a lot of moving about you may have to go back to mono jacks and plugs since the barrel of the housing gives you a positive grabbing surface. I don't think i have the mini mono phone jacks in the cable (end of wire) connector (just chassis mount). I can also sample these if you'd like to try them out.
<a href="http://www.kc6sye.com/2_wheresaneatpart.jpg" target="_Sparky">Is this plastic thingy on the counter a neat part?</a> <a href="http://www.kc6sye.com/1_casting_inprogress.jpg" target="_Sparky">Let's cast it.</a>
User avatar
MillenniumFalsehood
Posts: 17033
Joined: Tue Nov 16, 2004 5:23 pm
Location: Wichita, KS, USA
Contact:

Post by MillenniumFalsehood »

I'll be visiting an electronics store tomorrow that I wasn't aware existed when I made these posts. I'll see what he has, and if he doesn't have anything I need I'll try those items Tetsujin recommended. :8)

And yes, while I love Digikey's selection, that's also the number one reason I get headaches whenever I try to find something in their enormous catalogue. :shock:
If a redhead works at a bakery, does that make him a gingerbread man?

Ponies defeat a Star Trek villain? Give them a Star Wars award ceremony!
Post Reply