DC connectors for multi-voltage power supplies - Page 1
Forum section: electronics / projects

author: tkamiya
author_rank: Super Contributor
timestamp: May 25, 2019, 02:04:47 am
content: Over next couple months to years, I will be experimenting with many GPSDOs; both ocxo type and Rb type. It will involve long term tests. Some of them (Especially Rb type) will take 2 Amp or more at 12 to 24 volts until warms up. My plan is to make a separate power supply unit. (strictly linear supplies) I think I'd make it 24V, 12V, and 5V output, few amps each.Here's a question - what do you use for low voltage power connectors?I've been using terminal strips and 5.5mm/2.1mm barrel type. But having multiple voltage will likely result in release of magic smoke. Another idea is d-sub 15pin. Fairly uncommon and each can have multiple voltages. By paralleling pins, it should be able to support few amps.If you have good ideas, I would like to hear about it. Typically, I like building-in power supplies but for experiments and long term tests (especially), this will be costly and labor intensive.

author: bob91343
author_rank: Super Contributor
timestamp: May 25, 2019, 02:27:03 am
content: Try to select connectors that cannot be plugged into the wrong places. If you use d-sub, realize that much equipment does as well and you can cause problems.AMP and Molex make lots of cheap power connectors that are popular. You can use the old fashioned Jones plugs as well. My favorite is just a pair of banana jack/binding posts spaced the standard 3/4 inches. For several voltages you can mount a row of them and use different colors. The advantage here is that you can stack them and use the same power supply for multiple units. I have some that were salvaged from old stereo amplifiers as speaker terminals. Most of those have spring loaded buttons so you can insert wires without connectors. There are also old style screw terminal strips that can accept lugs as well as bare wires. These are available in groups from one to over a dozen.In short, the options abound, and you can have fun deciding. If you decide you don't like something, tear it out and change it for something else.

author: mariush
author_rank: Super Contributor
timestamp: May 25, 2019, 02:33:41 am
content: Classic barrel jackThe common Molex MiniFit Jr or "clones" (pci-e 6/8 pin , EPS/cpu connector on motherboards, atx 24pin)RJ45 (ethernet) ... gives you 8 wires in small footprint... but must label it properlymini-din (though i think would be poor choice)

author: David Hess
author_rank: Super Contributor
timestamp: May 25, 2019, 03:41:07 am
content: I like the Waldom Molex 1625 series for this type of application. The connectors can be used in-line, chassis mounted, (1) and printed circuit board mounted. They are keyed (2) and have a detent which holds them together with more than friction.https://www.mouser.com/Search/Refine?FS=TRUE&N=4292887429+4292906361The crimping tool and pin extractor are reasonably priced:https://www.amazon.com/Waldom-Electronics-W-HT-1921-CRIMPING-ELECTRONICS/dp/B0195UWT9Uhttps://www.amazon.com/Extractor-Diameter-Standard-Terminals-11-03-0002/dp/B00IZOD3NE/ref=sr_1_2(1) With a square hole punch unfortunately. You cannot have everything.(2) You can also swap male and female pins between the male and female housings to further key them.

author: sleemanj
author_rank: Super Contributor
timestamp: May 25, 2019, 04:28:41 am
content: Barrel jacks come in many sizes, pick 3, eg 5.5/2.5 for 5v, 5.5/2.1 for 12v, something smaller for 24v (the reason for using 5.5/2.5 for 5v is that it could feasibly fit and power into a 5.5/2.1 socket, so you'd only get 5v into a 12v desirous thing, not 12v into a 5v desirous thing).Or use XT30/60/90Or use USB for 5v, 5.5/2.1 for 12v, and something else for 24v.

author: FenTiger
author_rank: Regular Contributor
timestamp: May 25, 2019, 06:13:54 am
content: Anderson Powerpoles?They're good for more current than you're likely to need.They come in plenty of colours so you can colour-code the different voltages.They dovetail together in all sorts of ways, so you can construct configurations that won't physically plug into each other, for extra safety.They lock together fairly positively so they're unlikely to accidentally come apart during a long experiment.http://www.g0hwc.com/anderson-powerpole.html

author: jbb
author_rank: Super Contributor
timestamp: May 25, 2019, 06:24:23 am
content: +1 for Molex Micro-FitThey are fairly compact, have good current rating and decent insertion / locking behaviour. You can buy a crimper for many $ or buy pre-crimped pigtails from Digikey etc.No shielding or guaranteed connection order, though. If +24V and +5V mate before 0V, what would happen to your equipment?One word of warning: they are often knocked off, and mixing two different brands of knock-off could cause

author: MarkF
author_rank: Super Contributor
timestamp: May 25, 2019, 06:36:51 am
content: Computer disk drive pre-made 12" extension cables? Cut them in half or just cut one end off and toss the other.https://www.sfcable.com/12-in-5-25-in-male-to-female-internal-power-extension-cable.html

author: MosherIV
author_rank: Super Contributor
timestamp: May 25, 2019, 08:51:13 am
content: HiBe careful with current rating when using connectors like D-types and RJ45s.You can use multiple pins with the same voltage to share the current load.Try round DIN connectors. Somthing like thishttps://cpc.farnell.com/deltron-enclosures/610-0600/6-pin-nickel-standard-din-plug/dp/CN00039?st=6%20pin%20din%20plugsEach pin is rated to 2A.Is polarized.Semi self latching, does not fall out easily.Hope that helps

author: cs.dk
author_rank: Unknown
timestamp: May 25, 2019, 03:00:32 pm
content: I really like this type of connectors;https://www.tme.eu/dk/en/details/1-967623-6/automotive-connectors/te-connectivity/They're easy to crimp, can carry some amps, pins are easy to extract if necessary, the come in a panel mounted version.IIRC they are from 6 to 21 pins..

author: T3sl4co1l
author_rank: Super Contributor
timestamp: May 25, 2019, 05:01:22 pm
content: I've seen a lot of Molex KK (0.156" pitch) in old open-frame supplies.I've used Molex KK and SL (0.1") on hand-made protos before, and I frequently use 0.2" pluggable (Eurostyle?) headers where higher voltage/power is present. Think all my offline power supplies use a 5-pin header: hot, NC, neutral, NC, earth.Tim

author: soldar
author_rank: Super Contributor
timestamp: May 26, 2019, 02:33:05 pm
content: Depending on how often they need to be connected and disconnected.I have made connectors using barrel screw terminals. You can take a bunch of rigid wires and solder them on a strip of PCB and solder the cables to that. Then you just introduce the wires in the terminals and tighten the screws. There is no danger of mistakes or shorts.If it is something that needs to be connected and disconnected often and fast you could do the same with banana plugs.

author: Kjelt
author_rank: Super Contributor
timestamp: May 26, 2019, 02:53:01 pm
content: If its an internal connection you can use the Molex, but the tools are pretty expensive and you need to triple check the crimp for quality.If it is external connection I would advice connectors with mechanical cable strain relief.I myself use Neutrik XLR 3 the silver type for dual voltage medium Amps. Higher amps like motors I used the Silver metal SpeakCon connectors.