Baptistry safe or not safe?

[77naws]

I was recently asked if I could inspect my church's baptistry. The individual was afraid if the microphone hanging above were to fall in the water that someone could be electrocuted. I told him that I would look to see if the baptistry was properly grounded. I also told him that I thought most microphones were 12 or 24 volts and that it would be no danger. Would anyone have anything they could share about their experience with this?

 

[Smart $]

Professional audio systems often use 48VDC phantom-powered microphones. Generally, current is limited to a safe level. You can google "phantom power" and variations thereon for more info...

 

[TOOL_5150]

Not to mention if the mic preamp were to fail and send line voltage onto the mic cable. There has been an electricution, I cant remember when, but It happened to a priest when he was handed the mic while in the water.

~Matt

 

[iwire]

Many microphones have a path to ground through the sheild and metal body of the mic.

A pastor was killed when the baptistery was energized by a faulty and incorrectly wired electric heater.

The pastor and others where fine standing in the water as they had no path to ground, once the pastor was holding the mic and was in the water he was killed in front of the congregation.

Mike Holt has a paper on his site about it.

http://www.thesnowman.net/site/news/archive/309.pdf

http://www.1personalinjurylawyers.com/pi/news/baptism_elctrocution_lawsuit.html

 

[dbuckley]

Phantom power (where used) is 48VDC current limited by a pair of 6K8 resistors in each of the signal lines. To all reasonable definitions of the term, phantom is harmless. I say "where used" because for dynamic mics, phantom is unnecessary.

The bigger issue is either the baptistry becoming live (as the one noted above did) or the ground of the audio system failing and the microphone becoming live.

Thus a good move would be for both the baptistry and the sound system to be GFCI protected.

 

[ptonsparky]

Replace that mic with a wireless. He just needs an excuse to update his sound system anyway. Recommend GFCI protection for everthing in the area.

 

[LarryFine]

. . . a pair of 6K8 resistors . . .

Said in true European style.

 

[sparky59]

How would you protect the 48vdc mic with a gfci?

 

[mxslick]

How would you protect the 48vdc mic with a gfci?

The GFCI will protect a user from getting shocked when/if the audio equipment connected to the mic develops a fault. 99.99% of all pro audio gear is powered by the AC line.

And churches are notorious for having ancient audio gear that is either not grounded originally or has had the grounds removed by morons who don't know how to properly deal with hum issues.

ptonsparky said it best, install a wireless mic, loads safer.

 

[dbuckley]

And churches are notorious for having ancient audio gear that is either not grounded originally or has had the grounds removed by morons who don't know how to properly deal with hum issues.

Ain't that the truth - at least for old school churches - the Megachurches have concert level equipment and expertise.

ptonsparky said it best, install a wireless mic, loads safer.

Very true.

But that skill level thing comes in again. I wish I knew who it was that first noted that a thousand dollar wireless link works almost as well as a $5 cable...

 

[tom baker]

But make sure the baptistery has GFCI protection. They were added to the scope of the 2008 NEC, but even before it was to me a hot tub.

 

[K8MHZ]

Said in true European style.

It's the way we are supposed to be doing it, too. Some products coming into the US are already marked in that manner.

 

[tryinghard]

It is good energy spent to get this right, we'll answer to the Lord here!

Baptized and taken home all at once is efficient but we don't need to promote it. :grin: