Need chart of actual size to determine barrel connector size

you could look at the data sheets instead of buying.

The problem with barrel connectors is usually one of not knowing what you have in front of you (either the connector to be replaced

*or* it's missing mate)

"One of each" is the easiest way to handle this. There are many "universal" wall warts that come with a set of swappable connectors/plugs; this is an expedient for acquiring an assortment *and* having a usable power supply mated to same. Just "collecting connectors" has no *added* value!

Note, in addition to inner and outer diameters (neglecting connectors with a *third*, center "pin"), you also need to be wary of the length of the barrel as some devices may recess the OTS connector too far inside the enclosure and need a mate with "longer reach".

A micrometer or dial caliper can be used to check the OD of a cable-end connector; a drill index provides a handy reference for sizing the inner diameter.

In practice, you will likely find a few connector sizes cover most of your needs.

If you're trying to match something unknown just measure the mating part and check the connector datasheet. You have tools?

To measure the hole you can use a set of gauge pins (or a drill set if you don't have gauge pins), or do it (badly) with the pointy end of a set of calipers.

Measure the outside with calipers or a micrometer.

For example I have a 2.1mm hole in the female and the barrel OD measures 5.46mm with calipers or about 5.456mm with a micrometer.;;

This is called a 2 x 5.5mm or 2.1 x 5.5mm (the actual pin diameter is

2mm).

You also want to check the insertion length which may or may not be the same as the exposed length of the barrel depending on whether it's flush with the outside of the housing etc.

In my case the exposed part is shown as 12+/-0.5mm and the barrel part as 2.1 x 5.5mm in the detailed 10-page AC adapter specification.

The mating part is a CUI PJ-202A or similar.

Rick snipped-for-privacy@nomail.com wrote in news: snipped-for-privacy@4ax.com:

It looks like you are referring to inline crimp connectors for wire?

A set like this is handy:

Exactly. If you have the (adjustable) power supply to which they mate, all the better (cuz now you have a quick means of getting power into a random device that you've encountered). But, a lab supply will do, in a pinch.

[I routinely rescue these "universal power supplies" and have a large box of assorted "plugs" that accompanied each of them. Great when someone gives me a laptop or other device and forgets to bring along the power supply!]

Regardless, just take the time to document the dimensions of the individual plugs ("barrels") and then use them as go/nogo gauges for whatever connector you seek.

Sadly, the color of the plastic "tips" is largely meaningless (one could have hoped they'd have standardized on these, somehow)

Note the negth of the barrel can sometimes be a deal-breaker. And, I've encountered some barrels that have "wings" (for want of a better word) that allow the connector to be *locked* into it's mate (so it won't easily pull out).

Rick snipped-for-privacy@nomail.com wrote in news: snipped-for-privacy@4ax.com:

Perfect for any lab:

Perfect for your printer...

Some sizes mentioned, that is...

....

Yeah, but 'most of your needs' implies I'll need something more. Apparently there's nothing in that kit that fits my old Macbook, or the LaCie external DVD, or the Sony chumby.

My own needs are served by... haunting thrift stores and scarfing up the likely-useful-someday items. This Dell adapter mates to and runs the Samsung television fine, though I can't find either connector-part in any marketplace.

You've snipped "a few connector sizes" from that quote. Note that most of these "kits" have a dozen or more "tips" available to choose from.

If the LaCie is like mine, it's a 4 pin connector -- NOT a barrel connector. And, wired differently from many other identical connectors (i.e., my LaCie power adapters have been labeled "Only For Use With LaCie Devices").

[Note that the adapter kits often allow you to mate the plug to the cable-end in such a way that you can intentionally reverse the polarity -- center negative -- for those devices that use that convention]

My Chumbys use a regular barrel connector (though admittedly small OD and "long throat")

One of my /pro bono/ activities involves a "recycler" so it's (relatively) easy to find things -- eventually. The downside is that it is even EASIER to find other items (in need of power adapters) that can be rescued! :< So, the problem remains on-going, regardless of how many times I "solve" it!

The newer (3 conductor) barrel connectors "talk" to the device being powered so the powered device can refuse to power on if not fed by an appropriate adapter. This adds another "non-mechanical" aspect to fitting a supply to the device.

I keep a few cubic feet of power adapters (sorted by output voltage) on hand as my first stop for locating a power supply for a particular device. I also keep the power adapter aspect in mind when I choose to rescue a device (or not). E.g., I no longer will tolerate an external power adapter in something like an LCD monitor (which was common, years ago).

For items (REALLY) worth the effort, I will fit a different power connection to "remove" that dependency. I did this for a friend's portable keyboard (organ) some months back as the portable aspect was brutal on the original connector.

Common: DC power connector (source) inner is a conductive sleeve; various sizes outer, inner.

Weird variant: inner has a pin. It appears there may be as wide a range of various sizes as well.

BUT no specs, no sources; a variant connector will always be part of a device (say a small printer and its supply wall wart).

Anybody know where to find (and specify) a source of these connectors?