Why rotary-tip on 4mm banana plugs?

[MrCAL]

What's the advantage of the rotary-tip on some banana plugs?
One might argue it just add one more "problematic" connection-point?


Original Fluke prope from model 177. Can actually be unscrewed, which add yet another additional connection-point.





I did notice that when you insert the plug with a rotary-tip it does clamps/tightens to it's "body" and make good connection, but still an additional connection compared to the "standard" 4mm banana plug (picture 4)

[sleemanj]

Cheap to manufacture from stamped sheet.

The last picture are better (IMHO), they provide a reliable connection every time.

I have had too manu bad connections from the springy spinny ones (admittedly cheap ones), I even soldered a batch of them once to stop them spinning because they were so bad.

[Jeroen3]

The stamped metal sheet needs to elongate when inserted. There are some audiofoolery variants around where the flex mechanism is more fixed, but I suspect their mating cycles are a lot less.

Being a loose sleeve also makes it much easier to rotate when inserted compared to, for example, the one made from spring pins. (your last picture)

[tooki]

Cheap to manufacture from stamped sheet.

The last picture are better (IMHO), they provide a reliable connection every time.

I have had too manu bad connections from the springy spinny ones (admittedly cheap ones), I even soldered a batch of them once to stop them spinning because they were so bad.

The kind in the last picture are only good if it’s good quality product — I have encountered cheap versions of those where the bundle of wires has no springiness and just stays compressed after a few insertions. 

In a nutshell: any style is fine if it’s high quality, and any style can suck if it’s low quality.

[daisizhou]

This is the best

[tooki]

This is the best

Nope. (Not that one can really call one style the “best” anyway, since it also depends on what you’re mating it with.)

Those Pomona-style ones are short, and won’t mate with certain recessed banana plugs that expect the longer “European style” banana plugs. And they’re rated for 15A, while some from Stäubli and Hirschmann (of the lantern style shown in the very first image) can handle 32A.

[daisizhou]

This is the best

Nope. (Not that one can really call one style the “best” anyway, since it also depends on what you’re mating it with.)

Those Pomona-style ones are short, and won’t mate with certain recessed banana plugs that expect the longer “European style” banana plugs. And they’re rated for 15A, while some from Stäubli and Hirschmann (of the lantern style shown in the very first image) can handle 32A.

The best I mean,The banana plug and the shrapnel are integrated, so there is no possibility of poor contact.
The author of the first post said that the banana plug has a problem with excessive current and is prone to heat, causing the copper shrapnel to lose its elasticity.

[electr_peter]

This is the best

Nope. (Not that one can really call one style the “best” anyway, since it also depends on what you’re mating it with.)

Those Pomona-style ones are short, and won’t mate with certain recessed banana plugs that expect the longer “European style” banana plugs. And they’re rated for 15A, while some from Stäubli and Hirschmann (of the lantern style shown in the very first image) can handle 32A.

Yep, far too short. Exposed metal "ring" near plastic body is useless and make them effectively even shorter still, thus not reliable for many standard sockets. Also, that metal spring is questionable for reliability/low ohmic connection with higher currents.

Screw on connection for banana leads is very reliable and adds functionality to plug it in 4mm sockets with no extra* parts (*assuming you don't loose that piece). Other screw on adapters exists.
On general banana cables, many connection variants are fine as long as manufacturing quality is good.

[tooki]

This is the best

Nope. (Not that one can really call one style the “best” anyway, since it also depends on what you’re mating it with.)

Those Pomona-style ones are short, and won’t mate with certain recessed banana plugs that expect the longer “European style” banana plugs. And they’re rated for 15A, while some from Stäubli and Hirschmann (of the lantern style shown in the very first image) can handle 32A.

The best I mean,The banana plug and the shrapnel are integrated, so there is no possibility of poor contact.
The author of the first post said that the banana plug has a problem with excessive current and is prone to heat, causing the copper shrapnel to lose its elasticity.

True, there are no additional interfaces, but that style doesn’t make as much contact in total as the lantern style.

(Also I  only assume you’re using machine translation, because “shrapnel” is completely nonsensical in English for any part of a connector.)

The author of the first post said that the banana plug has a problem with excessive current and is prone to heat, causing the copper shrapnel to lose its elasticity.

Ummm… no they did not. They said nothing of the sort. Someone in a reply said they had ”bad connections” (without specifying them) with cheap versions of the lantern-style plugs.

High quality lantern-style plugs do not have that problem, and the lantern style contact is used in high-reliability connectors of all shapes and sizes precisely because it provides some of the best performance of any contact shape. It just needs to be manufactured competently.

(I have thrown out cheap versions of the Pomona style ones you like. They were made of cheap metal that deformed after a single insertion, making them useless. I do use real Pomona-branded ones of those, among others.)

[tooki]

This is the best

Nope. (Not that one can really call one style the “best” anyway, since it also depends on what you’re mating it with.)

Those Pomona-style ones are short, and won’t mate with certain recessed banana plugs that expect the longer “European style” banana plugs. And they’re rated for 15A, while some from Stäubli and Hirschmann (of the lantern style shown in the very first image) can handle 32A.

Yep, far too short. Exposed metal "ring" near plastic body is useless and make them effectively even shorter still, thus not reliable for many standard sockets. Also, that metal spring is questionable for reliability/low ohmic connection with higher currents.

Screw on connection for banana leads is very reliable and adds functionality to plug it in 4mm sockets with no extra* parts (*assuming you don't loose that piece). Other screw on adapters exists.
On general banana cables, many connection variants are fine as long as manufacturing quality is good.

Yep!

Sadly, on the Pomona ones daisizhou posted an image of, even on the genuine article (which I have many of), the rear stacking bores are a bit shallow and have a slightly large inner diameter, so most lantern-style plugs don’t mate with them, because the widest part of the lantern doesn’t make it into the bore!

Stupidest thing I ever got was some Pomona clones sold by Mueller, which used lantern-style plugs but with the short Pomona-style body, so they don’t stack with themselves. 

[The Soulman]

I prefer the second style in the first post, but only good quality (hirschmann) ones, I've somehow ended up with a couple "fake" ones I had to solder the "bulge" on one side to obtain a somewhat reliable connection.

The type on the third picture I only had bad luck with, including to less "spring" and therefore a sloppy connection and somehow the tips on the end breaking off.

[The Soulman]

Anyone used these style as sold by ab-precision?

[axantas]

The only ones I really rely on are the “Büschel plug connectors” - if they are of good quality. The combination with the removable rotary part are an interesting alternative, but if I can rotate them in mounted state (example two), I do not trust a firm connection.

[ebastler]

What's the advantage of the rotary-tip on some banana plugs?
One might argue it just add one more "problematic" connection-point?
Original Fluke prope from model 177. Can actually be unscrewed, which add yet another additional connection-point.

I believe you were not so much asking about the specific shape of the contacts (sheet metal or more massive), but about the fact that it can be unscrewed?

Point is, the Fluke tip is not really a banana plug. It is a pointed multimeter probe tip (which you would use most of the time, to probe circuit boards etc.), with the option to screw on a banana adapter (to plug it straight into a power supply or other output jack).

[The Soulman]

What's the advantage of the rotary-tip on some banana plugs?
One might argue it just add one more "problematic" connection-point?
Original Fluke prope from model 177. Can actually be unscrewed, which add yet another additional connection-point.

I believe you were not so much asking about the specific shape of the contacts (sheet metal or more massive), but about the fact that it can be unscrewed?

Point is, the Fluke tip is not really a banana plug. It is a pointed multimeter probe tip (which you would use most of the time, to probe circuit boards etc.), with the option to screw on a banana adapter (to plug it straight into a power supply or other output jack).

Oow, that makes sense, yes, from another brand I've also used crocodile clips and probe extensions that screw on to the probe with the same threads in place of that "banana-bit".
So yes, the reason that bit unscrews is to give the same set of probes/leads some more functionality.

[mawyatt]

Anyone used these style as sold by ab-precision?

We have similar types with the Blade Jack. These are OK except one must be very careful inserting in typical DMMs, the blade tips catch the edge of the Copper DMM socket. More of an issue with KS and Keithley than Siglent.

Also we've experienced all the issues mentioned with the various types of Banana Plugs/Jacks, even recently having a pair of new Pomona 1269 BNC to Banana Adapters become intermittent. Traced to a contaminated metal connection between the shell and blades on the Banana Jack, Pomona/Fluke Engineering was alerted to this (likely a bad batch).

Banana Jacks/Sockets are of many varieties, and many are from cheap sources, some OK, some not. It's a minefield out there wrt to all the various Banana types.

Best,

[tggzzz]

Anyone used these style as sold by ab-precision?

Staubli SLS4-B  SLS4-B/N  SLS4-B/E SLS4-B/E/N 30 VAC ~ 60 VDC / max. 19 A

I like them after I saw them being used on an HP3458A (albeit in a non-professional setting), by people that do know what they are doing. Stupidly, I didn't ask them why.

I hypothesise it is a relatively large contact area, low thermal mass, and gold plating.

[mawyatt]

I like them after I saw them being used on an HP3458A (albeit in a non-professional setting), by people that do know what they are doing. Stupidly, I didn't ask them why.

I hypothesise it is a relatively large contact area, low thermal mass, and gold plating.

Correct

Best,

[RoGeorge]

I've always thought that is to help rotating the cable without wearing out the connector.
Honestly, don't like them.  Also curious what's with all the fruit and animals naming. 

Banana plugs, crocodiles, parrot-beak hooks, alligator wires, crocodile clamps, etc, etc.

[IanB]

What's the advantage of the rotary-tip on some banana plugs?
One might argue it just add one more "problematic" connection-point?

I very much dislike them for this reason.

I have had too manu bad connections from the springy spinny ones (admittedly cheap ones), I even soldered a batch of them once to stop them spinning because they were so bad.

I soldered all of the spinning cage test leads I have because I got so fed up with the high resistance and unreliable contact. After soldering the connection became very reliable.

[tooki]

Anyone used these style as sold by ab-precision?

I don’t know who ab-precision is, but the original article made by Stäubli (formerly Multi-Contact), part numbers in tggzzz’s post above, are excellent.

In addition to the benefits that tggzzz listed and mawyatt confirmed, they also have the unique ability to be mated plug-to-plug on the male side, since you can just shove one plug into the other, and still use the stacking jacks on the backs. Their light weight also makes them ideal for test leads made of thin wire, so that there isn’t a heavy plug dangling off a thin lead. I used them to make banana-to-DuPont cables, for example. The way that their spring force works makes them fit snugly in basically any jack, yet without being annoyingly hard to use in tight jacks.

The downsides are that they only make solder versions of them, and just as mawyatt said, they can snag when inserting them into certain jacks, so careful alignment is sometimes necessary.

[tooki]

What's the advantage of the rotary-tip on some banana plugs?
One might argue it just add one more "problematic" connection-point?

I very much dislike them for this reason.

I have had too manu bad connections from the springy spinny ones (admittedly cheap ones), I even soldered a batch of them once to stop them spinning because they were so bad.

I soldered all of the spinning cage test leads I have because I got so fed up with the high resistance and unreliable contact. After soldering the connection became very reliable.

But that truly is only ever needed with cheap ones. High quality lantern-style plugs (e.g. Stäubli and Hirschmann) do not suffer from any of those problems, even after decades of use. (I’ve run into ones that are 40+ years old, and they still just work.)

[tooki]

I've always thought that is to help rotating the cable without wearing out the connector.
Honestly, don't like them.  Also curious what's with all the fruit and animals naming. 

Banana plugs, crocodiles, parrot-beak hooks, alligator wires, crocodile clamps, etc, etc.

Well, we humans describe things by things we know…

(Like how in the Middle Ages, in most European languages, exotic fruits they encountered for the first time were frequently called some kind of “apple”.)

Ever watch Dr. Pimple Popper (before she sold out to TLC) or Mr. PopZit? They are always comparing the contents of cysts with foods. 😂 Butter, pudding, mashed potatoes, smoothies, mayonnaise, …


And of course we can’t forget the ongoing (for years? Decades?) debate on Wikipedia about alligator clips vs. crocodile clips. Different dialects of English use different terms for different types of clips, unfortunately colliding with two conflicting meanings of crocodile clip.

But alligator wire? Never heard of that!

[electr_peter]

I've always thought that is to help rotating the cable without wearing out the connector.
Honestly, don't like them.  Also curious what's with all the fruit and animals naming. 

Banana plugs, crocodiles, parrot-beak hooks, alligator wires, crocodile clamps, etc, etc.

There are crocodile clips and dolphin clips (former long and straight, later with widening near jaw to grab big diameter wires).

[tggzzz]

Anyone used these style as sold by ab-precision?

I don’t know who ab-precision is, but the original article made by Stäubli (formerly Multi-Contact), part numbers in tggzzz’s post above, are excellent.

In addition to the benefits that tggzzz listed and mawyatt confirmed, they also have the unique ability to be mated plug-to-plug on the male side, since you can just shove one plug into the other, and still use the stacking jacks on the backs. Their light weight also makes them ideal for test leads made of thin wire, so that there isn’t a heavy plug dangling off a thin lead. I used them to make banana-to-DuPont cables, for example. The way that their spring force works makes them fit snugly in basically any jack, yet without being annoyingly hard to use in tight jacks.

The downsides are that they only make solder versions of them, and just as mawyatt said, they can snag when inserting them into certain jacks, so careful alignment is sometimes necessary.

I'd noticed that back-to-back feature, but haven't found it to be a benefit, as yet.

The leads used by the HP3458 owner I mentioned were indeed thin. After all, they weren't going to be carrying much current!