What is wrong with this picture VI - part b


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Continuing on from part a, these are the inserts from a 10A 250V rated Australian plug.

The one on the right is a new one, straight out of the packet. The others are not!



Here is the worst one out of the bunch, again, compared with the new one (on the right)


The worst one again, this time pluged into an inline recepticle (as seen in part a of this topic) and compared with a new plug (on the right)

Damaged by heat, I'd say. I guess something was drawing more than 10A, generating too much heat in the plug. Or, as copper is rather a good conductor of heat (as well as electrickery) perhaps the appliance got too hot on the neutral side (assuming Australian plugs are wired the same as UK one, although they look rather different).

There's no sign of carbon in the pins, so I assume the problem is with the appliance rather than what it was plugged into.

There doesn't seem to be any provision for a fuse in the plug, which might have alerted someone to a problem. All domestic UK 13A plugs are fitted with a fuse (3A, 5A or 13A), which is there to protect the wire to the appliance (not the appliance itself or the user - a false assumption made by many). In the lighting world we still use the good old round pin 15A plugs, which do not have fuses. But then we know what we're doing, don't we???
Seems to me like you guys need to invest in better quality plugs in staying otherwise silent.

Mayhem Musical Productions... known for the melted plugs in the industry. :p

Note this is a at times common thing to see no matter what side of the world you are on and his seeing these things does not reflect the quailty of his equipment or ability as a disclaimer. On the other hand, I'm sure there are some better plugs on the market still.
You’ll keep!

The rest of the Australian and New Zealand members here will support me in saying that these are (all in all) a good and resilient product.

I will be the first to say that there could be some improvements in their design but in all reality a fairly robust item.

The other advantage is that this is the only single phase plug that we use. There are 15A and 20A versions, but with the exception of the size of the ground pin, all are the same. Thus, you can plug a 10A plug into a 15A outlet, but not the other way around.

When it comes to 3 phase, again, we have a single plug.

Therefore, the great thing is that we know that whatever venue we walk into, we can plug into their power. I am still in amazement at the number of different plugs and receptacles that you guys have in the US. This must make it fun if you work in more than one venue or hire equipment.
Fun, oh' yes. Beyond straight blade "Edison styles" that in the 120v/20a version will thoroughly confuse stage hands into installing new 15a versions of the plug on the cable so they will fit into the 20a outlets. To twistlock, to stage pin. Adaptors abound everywhere in our industry - especially twist lock type adaptor. Depends upon when the place was built. Even have two or three places that use a twist lock alternative that's non-NEMA in having a fourth style beyond just 15 and 20a versions of the twist plugs without a standard.

Plus there is 120/208v switchable moving lights that require either adaptors that are against good practice in converting between the two voltages or the various adaptors to a set of dual voltage stage pin plugs taped in between to make it work say from 20a twist/208v to Edison.

Than now we are getting into the Euro pin and sleeve plug such as the Cee Form 16a version. Darned Led cyc lights that now need adaptors to the above stuff in addition to. Much less the Kenisis hoist system using 5-pin Cee Form instead of 5-pin twist I already have, I'm building even more cable for next week. This as opposed to just more adaptors.

The CEE Form type of pin and sleeve style of plug itself has differing voltage and style ratings as I found out later in having to re-install the plugs on some adaptors after having found out later hey were not the same.

Than there is even equipment using the ML series if not the Speakon/Powercon type of plug, or even 3-pin XLR plugs for a power/data signal.

Lots and lots of adaptors abound here.
Well, talking about the types of plugs in the U.S., we started out with stage pin (the most common). Later, after techs got tired of ripping gaf off sp plugs, sombody invented twist lock, wich locks the spliced cord together. After that, some one else invented twist lock, then some one else, and someone else, and so on, making two "twist lock connectors" not connect. ??? I know, but that is why we either use low power intraments with edisons, or spend money on lots of gaff, to link connectors together, or just use a certian type of twist lock - wich ever you perfer. If someone else has any meathos, let me know.

P. S. Are socapex cabes standardized?
well they are kind of standardized. I believe the connectors are all the same, but depending on the shop they may be wired differently. I know where i live, both shops wire there socapex differently.
thelightguy said:
P. S. Are socapex cabes standardized?

Soco instead of Socapex is the general standard for the multi-cable industry both with sound in some cases which causes it's own problems when they borrow, and with lighting.

Really Socapex as a brand of plug is the old standard, the Litton/Veam VSC series is more the standard for a darned better plug than the old Socapex one. Say Soco, and it means a style. Say Socapex, and it's like GE for a brand. Socapex itself came out with an improved version that's better than VSC - that is as long as installed right and in certain circumstances. Can be really rough if the supplier installed the removable insert strain relief backwards and suddenly those strain relief inserts break free and shoot out the rear of the plug in it no longer having a strain relief than. Much less if you have other than 18 wire cable fed by the plugs.

Lots of suppliers of a 19 pin Soco type plug, it's the standard over other types of plug for the lighting industry as a plug standard even if others wire it differently.
Ok - remember in one of the very first pic type questions, Ship mentioned a simple fact that will help you to narrow down the cause of such problems.

If the wire in the plug is trashed, and as you cut further down the lead (away from the plug) you notice that the wire is also trashed then the problem was that the lead and plug were overloaded.

Now - look at the wires on these plugs (I even stripped the insulation off before taking the pics). The wire is good condition.

Therefore, either what these plugs were plugged into was at fault. Or there was a poor connection between wire and terminal inside the plug.

In fact, all these damaged plugs came out of the one venue (actually, on two separate shows). My feeling was that their portable 3 phase distro was the problem in having a bad connection somewhere within. Reported it but was ignored. After noticing it on the second occasion, I was sure and when going back after that, I took my own distro with me. No problems, despite using the same equipment.

Such observations are important in not only working out what happened, but in identifying when something in your inventory needs attention.
Thanks, everyone, I haave just always heard them called Socopex, Maybe I was using it in the wrong context?? Well, forget it- And mayhem, is not it a bit dangerous how you wreck havoc with electricity all for the sake of the Q of the week? Or do you find these types of things around?
thelightguy said:
mayhem, is not it a bit dangerous how you wreck havoc with electricity all for the sake of the Q of the week? Or do you find these types of things around?

LOL – well I don’t go walking around with a big bucket of water to throw at a distro or any such thing but over the years, things do happen and when they do I am trying to remember to keep them or at least take pictures of them.

Sometimes I see things on shows but cannot take pictures of them because of either getting into trouble or not having my camera with me at the time.

In this case, these plugs all melted at the one venue on two different shows. Rather than throwing them in the bin, I kept them to show to the venue manager. He didn’t really care too much and said it was obviously my equipment. Happened a second time and on subsequent jobs there I used my own distro. When using my distro, no melted plugs, despite the same amps, lights, controllers etc being used on all shows. I later heard from someone else who has worked there that similar things have happened to them as well. I was cleaning up my workshop a few months ago and found them in a box, so I thought that they would be ideal for this.

The PAR can post (which was the first of this type of QOTD) was discovered when I serviced some cans that I had picked up second hand. The fury amplifier pics were on my computer from when I serviced that particular amp some years ago. Found them when looking for something else. The lamp pics and the stripped wires, melted bus bars and stage pin plugs were sent to me by Ship and I am always on the look out for such pictures.

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