Cable and connector recommendation - Page 1
Forum section: electronics / projects

author: SkipMorrow
author_rank: Contributor
timestamp: October 06, 2018, 10:10:14 pm
content: What kind of cable & connector recommendation would you suggest I use for my portable scoreboard project? I need ten conductors for six feet to connect a control box to a scoreboard panel. The LED power will require 12V/2.5A total (for all segments), but that will be split over two wires for pos and two wires for gnd. The for shift registers will require five volts and that will be carried on one of the ten wires as well (for a total scoreboard power of just under three amps). It will be connected and disconnected once or twice a week, and the conductors are exposed (but I don't really need to worry about them getting wet because we don't play in the rain).I was thinking about a ten conductor molex like this:Receptacle:https://www.digikey.com/product-detail/en/molex-llc/0395321010/WM7851-ND/1280702Plug:https://www.digikey.com/product-detail/en/molex-connector-corporation/39530-0010/WM7824-ND/1280675Initially, I was going to use 22/24 gage, but I think I will have too much trouble with wires coming loose, and with all of those connects and disconnects, and the typical friction of a molex connector, that I could also be dealing with broken wires.I was thinking I could go with 18 gage, but I fear I will still be dealing with wires coming loose.Also, I would like a bundled wire solution. Having ten loose wires seemed a little annoying, even if I wrap them, but that would not have been a deal breaker.I guess I COULD use this molex connector on the control box end since that will rarely ever be disconnected. But I sill need to put some thought into the end at the panel which will be regularly connected and disconnected.Thoughts?

author: SkipMorrow
author_rank: Contributor
timestamp: October 07, 2018, 05:26:30 pm
content: So I have come to the conclusion that what I really need is a panel connector. Round connectors like these are probably the way to go:https://www.mouser.com/Connectors/Circular-Connectors/Standard-Circular-Connectors/Standard-Circular-Connector/_/N-av49j?No=25&P=1yvgchwZ1yzv7x2But I wonder if there are any that are DIY-friendly? I think the panel mount side is pretty easy (generally they seem to use solder cups for each pin). But as for the cable, it seems that most (maybe all) use proprietary pins. I really don't want to spend a bunch of money for a single use pinning tool. Anyone know of a DIY-able connector that might work for me here?

author: Bratster
author_rank: Frequent Contributor
timestamp: October 07, 2018, 05:33:22 pm
content: There are definitely a lot of those types of circular connectors where the pins are independently chosen from the connector body. They usually have the option to use either crimp pins or solder pins.Are some of the nicer connectors even if they only come with the crimp ends that you're supposed to use like an indent crimper for, you can still just solder those by hand since it's basically a wire cup.Sent from my Fi Moto x4 using Tapatalk

author: drussell
author_rank: Super Contributor
timestamp: October 07, 2018, 06:20:34 pm
content: I like the AMP CPC series for applications like this. The housings in the middle sizes are only about 5 bucks and the male pins and female socket-pins are available in multiple wire size ranges and are interchangeable between the male and female versions in the same housings, whether they're the panel mount or inline type connector. They screw-on like a typical military connector but are plastic so they're affordable but still quite durable.Traditionally all of the portable scoreboards I remember seeing used the old Cinch connectors with the flat pins, like this:You used to see those everywhere because they were cheap and readily available but they're not the best kind of "locking" and the pins are rather exposed if only partially plugged in.

author: SkipMorrow
author_rank: Contributor
timestamp: October 07, 2018, 09:11:16 pm
content: Yes! I remember seeing those types on connectors in the militaryI should have thought of that.So, it seems though that these do require a special tool to crimp the connector pins (which, of course, are not included). Are there any alternative crimpers available? Checking amazon and youtube now 'cuz I'm not spending $300+ on a crimping tool...

author: donmr
author_rank: Regular Contributor
timestamp: October 07, 2018, 11:01:19 pm
content: They make solderable pins/sockets for the CPC connectors. Make sure to get the strain relief backshells too.

author: drussell
author_rank: Super Contributor
timestamp: October 08, 2018, 06:39:42 am
content: Quote from: SkipMorrow on October 07, 2018, 09:11:16 pmMy $10-15 generic ones of the correct size work just fine. Actually, it might be one of the actual Molex or Waldom or something brand cheap, non-ratcheting version ones that I have (about $25) that fits those CPC pins. I have several different sets of cheap crimpers of different sizes and I can't remember off the top of my head which ones I actually used last time on CPC pins. IIRC, I think they were one of the sets that I have which have two different sized slots in them like the first photo below, but they have red handles and aren't spring loaded. So helpful.(Or use the solder-type, of course...)This is where actually having a local physical store you can go in with a couple of your contacts and actually check to find a generic one that fits your pins properly. I wouldn't pay a zillion dollars for one either unless I was making cables all day long. With a little care and the correct size and shape of crimper, even a dirt cheap generic tool will make proper, firm, ultra-crimps. Something like one of the ones below, all are about $25 CAD:

author: mariush
author_rank: Super Contributor
timestamp: October 08, 2018, 06:55:15 am
content: You don't HAVE to use connectors with EXACTLY 10 pins .If this is not a commercial project, a good idea may be to repurpose a very common connector that would be very cheap to source, like a D-Sub connector, for example get a DB-15 one and use multiple pairs for power (if it's even needed, in theory each pin in the d-sub connectors can carry up to 5a).If you go that route, you have options, you can go with connectors likethis onethat have pins, so you can solder a tiny pcb with a single connector to it (or two, one for power and one for data) or you could get one likethis onewhere you can simply get a ribbon cable and press-fit it and then solder the ribbon cable to your pcb or install a connector to go in your pcb.And these d-sub connectors also have ready made holes through the metal, allowing you to easily screw them to a case.AND you don't have to mess with crimping tools if you don't want to this way. And you'd be able to simply reuse a commercial vga cable to connect your two devices. There's plenty of vga cables around that length you want.ps. also why carry 12v AND 5v through the cable, couldn't you simply add a LDO or a tiny switching regulator to produce 5v from 12v? The voltage drop will be small on 6ft of cable but nevertheless will still be something. But if you lose the 5v and get the number of wires down to 8 or less, you would be able to even repurpose an ethernet cable and ethernet jacks and simply use 6-10ft ethernet patch cords between your devices.

author: SkipMorrow
author_rank: Contributor
timestamp: October 08, 2018, 10:51:43 am
content: This is a one-off personal project (making a scoreboard for my weekly Ultimate Frisbee pickup games). I have thought about the DB15 route, and that's a good one because it also helps me with my other problem--finding a suitable cable. I also don't have to worry about building the connectors. I guess the one downside is that I never really thought of these types of connectors as being the type to be connected and disconnected a lot. I think they are more meant to be connected and stay connected. But if I bend a pin, they are cheap so I can just buy a new one.Definitely giving this one a lot of thought.

author: helius
author_rank: Super Contributor
timestamp: October 08, 2018, 11:18:10 am
content: D-subminiature connectors are one of the oldest military connector designs still in use, so they are definitely available in high quality rated for thousands of insertions. One issue with the design is that it is not "scoop proof". If the connectors are mated at a deviated angle, it is possible to hit the pins with the connector shell and bend them; correct mating requires the user to visually guide the connectors together. A similar issue exists when detaching the connectors. Better designs like DTL-38999 have recessed pins to prevent scoop damage, and allow safe blind mating or removal.

author: Nauris
author_rank: Regular Contributor
timestamp: October 08, 2018, 06:15:38 pm
content: 16-pole Harting Han A connectors are what I would use, they are big enough that they withstand even bit harder field use very well.Bit pricey if you have to buy new, but so far I have found enough of them from the scrap yard. Usually they are screw terminal, so easy to install wires.https://www.digikey.com/product-detail/en/harting/19200161540/1195-3082-ND/3181667https://www.digikey.com/product-detail/en/harting/09200162612/1195-1820-ND/3180403