That little A/C receptacle tester....

[seamonkey]

Many power conditioners, especially the crude switching transformer tap type will trip Arc Fault breakers that are showing up everywhere. A few incidents of tripping a breaker for no good reason is a huge irritation.

 

[lowplaces]

I would say that you should have a high confidence level employing the method you have described, but to be even more "belt and suspenders" sure, you could also employ a two wire neon lamp tester to test for a difference in potential between the grounded parts of cables originating from two different pieces of equipment. You could also use a screwdriver style capacitively coupled neon tester to sense voltage on a grounded part of a single cable. The ionization Voltage of neon is about 60 VAC, and maybe 90 VDC, so this type of tester would not detect a fault that presented voltages below that magnitude.

If I was not in the US, but some third world, or notoriously unsafe country, I might employ all of the tests, and maybe include some visual inspection of my own before risking damage to very expensive equipment. Even though I am aware of how to, and have all the tools needed to check out venue power, I have to admit, that we have not made it a practice to even use the basic outlet tester we always carry with us the first time we are at any venue.

Okay, good deal then. I'll read up on those testing methods later this evening when I get off work.

Thanks for taking time to reply as always.

 

[Hoochie Coochie Man]

Too true. But a commercial establishment should be 20 Amp service.

The male end of my extension cord is one of these:

View attachment 2838294

Not in the dives I work.

Edit: FYI. Sorry if it seems I am being pedantic, but the term "service" has a specific definition as used in NFPA 70 that is not used to describe the circuit, or equipment referred to in your post. There is a good reason for all the terms used in the code. In fact, it is important enough that Article 100 exists for the purpose of providing definitions for the terms used. Article 100 defines what you are referring to as a "branch" circuit.

 

[Hoochie Coochie Man]

Many power conditioners, especially the crude switching transformer tap type will trip Arc Fault breakers that are showing up everywhere. A few incidents of tripping a breaker for no good reason is a huge irritation.

It's been quite a few years since I have done any residential work other than some minor repair, but maybe ten years ago or so, when I was doing electrical work as a side job, and after AFCIs were first referenced in the code, (I think required for bedrooms in certain occupancies) the AHJs in my area did not enforce it in the remodel work I was doing, and I don't think they even required it in new construction. In fact, I have yet to see an AFCI installed anywhere. I bet that it is likely to be required in larger metropolitan locations like Chicago perhaps. I'm in the "lake country" west of Milwaukee, but difinately not the boonies. Lots of very fancy high dollar houses here. I was surprised after seeing the first AFCI reference that it never eventually was, (as far as I know) adopted around here.

 

[beans-on-toast]

Back when we were doing television remote broadcasts on a regular basis, we usually saw the ground loops in the video before we noticed them in the audio. But fix it one place and it got fixed everywhere.

Everything seems to be digital these days. Computer networks slinging data here and there, people editing remotely in real time. Equipment is very different.

 

[Hoochie Coochie Man]

All this electrical talk makes me want to go and fix, or install something. My arthritis says don't even think about it. I should quit buying new tools I'm becoming too decrepit to use.

 

[SurferJoe46]

All this electrical talk makes me want to go and fix, or install something. My arthritis says don't even think about it. I should quit buying new tools I'm becoming too decrepit to use.

I hate that to --- picking our activities now in a as-needed category - not a fun-thrill one. My bucket list has some holes in it.

 

[Old Garage-Bander]

Everything seems to be digital these days. Computer networks slinging data here and there, people editing remotely in real time. Equipment is very different.

And that presents it's own set of problems.

Everyone thinks that just because the tools are cheap and readily available, that it's easy to produce a quality product. Fact is, it's done nothing but flood the media with a lot of third rate production crap. Because there is so much of it, it has become "acceptable."

The tools are only as good as the person using them. Give the average person on the street a DSLR, and have him film, edit and narrate a five minute documentary about the #2 pencil. Then give the same DSLR to Spielberg, or even a second year college film/video student, and you get a whole different documentary. It will be something worth watching because it includes production techniques that help make the subject matter more interesting.

Exhibit #1. People who shoot amateur video on their phones that they intend to show on a monitor.
The monitor is wider than it is tall, yet they hold their phones vertically, which forces the picture to be much smaller than it could be. Two-thirds of the screen is black. I've even heard people say that they wish there was a way to fix that.
%#%€£^! People, get a clue.
Hold your phone horizontally.

 

[Old Garage-Bander]

After reading through the thread I have a couple of questions. Say I am at a gig and my amp is plugged into a 3 prong receptacle that tests good with both of these type testers.

View attachment 2838265 View attachment 2838266

The sound man approaches me with a XLR cable to plug into the back of my amp. He is using a separate outlet and the outlet he is using also tests good with both type testers.

Is it safe to say there will be no issues assuming that the cable connecting my amp to the board is not faulty ?

If the answer is yes, what if a keyboardist and a guitarist are also running a line to the board, and each of them are using a separate receptacle to power their gear, and both receptacles they are using test okay with both types of tester. Again assuming no faulty cables are being used, are we good to go ?

100% sure ?

Its never 100% certain. The equipment as well as the venue all have to meet code/be properly wired, connected and operated. Too many variables under the control of too many different people to ever assume 100% safe, 100% of the time. If someone could make those kinds of guarantees, your insurance rates would be a lot lower.

 

[Wild_Bill_57]

Several people have brought up a good point, plugging different rigs into different outlets and the outlets being wired differently. This is where a stage stringer comes in handy. Everything plugged into the stringer is wired at the same potential. Find a properly wired source, plug in a stringer, plug everything into the stringer. For those not familiar with a stage stringer, they are a cable with 4-5 outlets spaced 10-20ft apart. Most bands can easily run on a single 20a circuit not including any lights.​

 

[beans-on-toast]

And that presents it's own set of problems.

Everyone thinks that just because the tools are cheap and readily available, that it's easy to produce a quality product. Fact is, it's done nothing but flood the media with a lot of third rate production crap. Because there is so much of it, it has become "acceptable."

The tools are only as good as the person using them. Give the average person on the street a DSLR, and have him film, edit and narrate a five minute documentary about the #2 pencil. Then give the same DSLR to Spielberg, or even a second year college film/video student, and you get a whole different documentary. It will be something worth watching because it includes production techniques that help make the subject matter more interesting.

Exhibit #1. People who shoot amateur video on their phones that they intend to show on a monitor.
The monitor is wider than it is tall, yet they hold their phones vertically, which forces the picture to be much smaller than it could be. Two-thirds of the screen is black. I've even heard people say that they wish there was a way to fix that.
%#%€£^! People, get a clue.
Hold your phone horizontally.

Inexpensive tools allows people to do things that you could never do on your own. I remember editing video in a suite with a control console and multiple tape machines. You would use the editor to piece together the video onto a master recorder. You had to book a suite. Today a kid with mac can do a lot more with way better results.

The technology for connectivity is pretty impressive in high end equipment. The Dante IO bridge that they talk about here allows for a lot of routing and conversion flexibility. Latency is not a problem over relatively large distances.

 

[Wild_Bill_57]

Another interesting point to consider. Code typically requires type SOOW cable for use on stages. Most premade extension cords you buy at "Big box hardware stores" are SJTW and not code compliant regardless of gauge. Just food for thought.

 

[Hoochie Coochie Man]

Another interesting point to consider. Code typically requires type SOOW cable for use on stages. Most premade extension cords you buy at "Big box hardware stores" are SJOOW and not code compliant regardless of gauge. Just food for thought.

The "J" in SJOOW stands for "junior", which refers to the insulation voltage rating, which for this type is 300 Volts.

SOOW insulation Voltage rating is 600 Volts.

S means rated for heavy service.
The first O means the jacket is oil resistant.
The second O means the individual conductors insulation is oil resistant.
W means water resistant.

 

[Wild_Bill_57]

I went back and did look at this a little closer, you are correct Hoochie Coochie Man, we had a few run ins with local inspectors that required all SOOW at a minimum of 12 awg on all stages. We adopted this years ago to avoid issues, so it had just stuck in my mind as code. Sorry if I'm mistaken.

Same inspectors also do not allow metal "quad boxes", everything we used is "Woodhead 3000 series" or equivalent all rubber boxes on stages. We also use cable ramps at any point that people walk across.

 

[Wild_Bill_57]

You could just cut to the chase and use one of these fine products

 

[Hoochie Coochie Man]

I went back and did look at this a little closer, you are correct Hoochie Coochie Man, we had a few run ins with local inspectors that required all SOOW at a minimum of 12 awg on all stages. We adopted this years ago to avoid issues, so it had just stuck in my mind as code. Sorry for the mistake.

Wild_Bill_57. My post was not made because I noticed any error on your part. I posted to explain (to to my knowledge, at least) what the difference was between the two types of cord. In fact, as you made your last post, I was about to edit mine to add a disclaimer stating that I may be wrong, and inviting anyone with more knowledge than I possess to correct me.

All of the discussions in this thread have caused me to spark my brain to try to remember things I learned mostly by studying books in the library at the local community college many years after I had studied electronics there back in the mid-1970s

 

[agedhorse]

Right angle plugs certainly take care of the strain on the cable provided the direction of the cable exit is down.

Most of these pluses will not accept #10 gauge type S in either the terminals or the strain relief.

For legitimate stages, type S (S, SO, SOW) is required, J is not acceptable.

 

[Drgonzonm]

I went back and did look at this a little closer, you are correct Hoochie Coochie Man, we had a few run ins with local inspectors that required all SOOW at a minimum of 12 awg on all stages. We adopted this years ago to avoid issues, so it had just stuck in my mind as code. Sorry for the mistake.

Several people have brought up a good point, plugging different rigs into different outlets and the outlets being wired differently. This is where a stage stringer comes in handy. Everything plugged into the stringer is wired at the same potential. Find a properly wired source, plug in a stringer, plug everything into the stringer. For those not familiar with a stage stringer, they are a cable with 4-5 outlets spaced 10-20ft apart. Most bands can easily run on a single 20a circuit not including any lights.​

Same inspectors also do not allow metal "quad boxes", everything we used is "Woodhead 3000 series" or equivalent all rubber boxes on stages. We also use cable ramps at any point that people walk across.

Just a question, are the recpts you are plugging your stringers rated at twenty amp? The recpt Wii have one vertical and the other a lazy tee prongs. Also, do the AHJ require 20 amp plugs? One vert one horz flat blades? Reason I am asking, our group was requested to put a wish list, to use county owned amps and speakers. The venues have 20 amp recpts,

 

[Wild_Bill_57]

The input on my stingers are twistlocks either 5L20, 14L20, 21L30 depending on how many circuits are in the stringer. I have adapter Cables from 5-20 straight blade to 5L20 twistlock for if I'm using a stringer without a portable power Distro. Most commercial building will have 20a outlets with the 1 blade both vertical and at 90 degrees.

 

[Hoochie Coochie Man]

Regarding right angle plugs and heavy cords, and the orientation of NEMA 5-15, and 5-20 receptacles.

As far as I know NFPA 70 does not specify whether 5-15 or 5-20 receptacles shall be installed so that the grounding pole is above, below, or on the left, or right hand side of the other poles in the device.

I default to installing receptacles with the grounding pole above the other poles whenever practical, (unless someone requests otherwise), or for a horizontal orientation, I put the grounded, (neutral) pole above the phase pole.

I would not make up a cord and plug with the idea that the orientation, or withdrawal force alone will ensure a reliable connection.

Heavy cords should be terminated with twist-lock style plugs to ensure they are not inadvertently disconnected while in use.