Getting shocked by the pa

[1958Bassman]

I guess rubber gloves and a dental dam would work, but it would sound bad.

[bassmeknik]

Originally Posted by 1958Bassman

I guess rubber gloves and a dental dam would work, but it would sound bad.

nice...

[jmclearnon]

I remember playing at a jazz orchestra and the guitarist beside me got shocked on his arm while strumming, burnt his arm and that was the lucky escape! Could have been fatal!

When it comes to safety and electricity you have to abide to law.....

you could be a dick and report them to the authorities if they refuse to fix it..........

[MNAirHead]

Funny about gloves etc...

I gig in the real world ... A buffer between my face and mic is wiser than reporting an issue... I'd have to be shocked to know about the issue

I'm sure I've played many venues that I could have been shocked at

---

I keep a ground indicator on my pedal board-- about 10% of the time I'm looking for better power--- it will never indicate if ground and neutral are really directly bridged

[MNAirHead]

This is on my pedal board

I have a gfi on my power cord

[MNAirHead]

Originally Posted by Chad.mundt

So the house pa that I frequent shocks the band. The house guys won't let us touch it, so I'm wondering what fixes you guys have for keeping it level at our face.

One thought is a mic cover (sic) but is that going to do the job?

You can use the ground tester and a 12awg extension cord to a better outlet

[john m]

Originally Posted by MNAirHead

Attachment 308857

This is on my pedal board

I have a gfi on my power cord

When the tester gives you anything but a "good" reading.

Open ground?
Hot and Neutral reversed?

[MNAirHead]

Always both+windsock

[baba]

Possibly related...

Is powering PA/amps/electric band gear off of anything more than one circuit a bad idea due to shock hazards? I've always heard this, but I would suspect it isn't practical in large installations that far exceed 20A.

I know AC basics, but not enough to make safety judgements on it.

[bassmeknik]

Originally Posted by baba

Possibly related...

Is powering PA/amps/electric band gear off of anything more than one circuit a bad idea due to shock hazards? I've always heard this, but I would suspect it isn't practical in large installations that far exceed 20A.

I know AC basics, but not enough to make safety judgements on it.

In the US homes and businesses have what is called 220Volt single phase power. This is really two separate legs of 110 Volt power that can be combined to make 220 Volts. If multiple circuits are required it is advisable to try and use the same leg of power to prevent the possibility of their being a 220 volt differential between devices. A larger (and more established) club near me has all the numerous power plugs named by circuit number and marked leg A and leg B for just this reason. They also have a wall of neon lights near the stage and all the circuits have interference.

[Keithwah]

Originally Posted by bassmeknik

In the US homes and businesses have what is called 220Volt single phase power. This is really two separate legs of 110 Volt power that can be combined to make 220 Volts. If multiple circuits are required it is advisable to try and use the same leg of power to prevent the possibility of their being a 220 volt differential between devices. A larger (and more established) club near me has all the numerous power plugs named by circuit number and marked leg A and leg B for just this reason. They also have a wall of neon lights near the stage and all the circuits have interference.

And it severely minimizes hums, buzzes, hum bars in video, just general grounding troubles. All Audio and Video equipment that are integrated together, whether in a large scale installation or a club band situation, should be powered from the same electrical phase and away from all dimmers, motors and fluorescent/neon fixtures. This would includes projectors, flat panel displays, all video processing equipment, all audio processing equipment, and also all stage gear. You can pull stage lighting from the other phase with the rest of the trouble makers.

So what is happening here is that your stage rig is coming from one phase and your PA is coming from another phase. Add in the use of unbalanced guitar cables that are not truly a grounded device (using foot pedals in line can essentially lift a ground and create the potential for you to become the grounding point between point A and point B too.

Hardly any clubs are wired properly as we have just really been ironing out and fine tuning A/C power and shielding to the point of understanding the depth of how A/C power will affect the craziest things in an A/V or audio system. If not building from the ground up, you can't get an existing club or venue space to rewire the buildings power to suit the needs of your production. Hell, just be glad the jags can pay you at the end of a show.

So much has changed in the industry as far as quality manufacturing has fallen with pricing. You really need to always keep a nice arsenal of audio isolation transformers on hand to cope with life's surprises. For all the amazing things that modern digital signal processing can do, none of these units have as much RF shielding rejection built into them in order to minimize costs.

[testing1two]

Originally Posted by 1958Bassman

What does that do for the cables when the plugs are grounded metal or the guitar strings are grounded through the bridge?

The windsock protects against one of the potential shock hazards but not all of them.

Read this: http://www.guitarnuts.com/technical/...fety/index.php

[gareth dunster]

I was having similar problems in our studio until I realised that the industrial wiring was three phase allowing for quite large voltages between the 240 v circuits, (415v across phases). Once all sockets off the same phase were used no more shocks to the mouth.

[copressit]

Sorry, but there is no way I am going to troubleshoot phase or grounding issues in every venue I play. I do alot of singing, and discovering grounding problems through the moist areas of your mouth is not pleasant. My mic ALWAYS has the foam condom on. It is a perfect fix for my peace of mind.
OP, does this grounding issue affect other bands beside your own? The same complaint coming from different people may make a difference in getting someone qualified there to get this resolved.

[john m]

Originally Posted by gareth dunster

I was having similar problems in our studio until I realised that the industrial wiring was three phase allowing for quite large voltages between the 240 v circuits, (415v across phases). Once all sockets off the same phase were used no more shocks to the mouth.

I've seen 480/277 and 208/120.
What system suplies 415 across two phases?

[PilbaraBass]

^youre thinking in terms of North American voltages... Here in Australia. 3-phase low voltage is 415 p-p and 240 p-n

[baba]

Originally Posted by bassmeknik

In the US homes and businesses have what is called 220Volt single phase power. This is really two separate legs of 110 Volt power that can be combined to make 220 Volts. If multiple circuits are required it is advisable to try and use the same leg of power to prevent the possibility of their being a 220 volt differential between devices. A larger (and more established) club near me has all the numerous power plugs named by circuit number and marked leg A and leg B for just this reason. They also have a wall of neon lights near the stage and all the circuits have interference.

That makes complete sense and is a great detailed confirmation of what I've always heard. Thanks.

[modulusman]

As someone mentioned earlier it could be the bands gear. I have heard that old vintage amps can cause problems.

[PatQ]

Originally Posted by modulusman

I have heard that old vintage amps can cause problems.

As can brand new out of the box ones.

[john m]

Originally Posted by baba

That makes complete sense and is a great detailed confirmation of what I've always heard. Thanks.

The phases are marked so that all of the load is not put on the same phase--- load distribution.

Otherwise the stage would have been wired on one phase.