lightning protection for powered speakers

B

Ben Gingerich

Sophomore
Oct 19, 2012
188
0
16
Warner Robins Ga
I have a church install where they want to hang some powered QSC MD cabs from another campus in their building 30ft up, there is already power run up there and there is no way to turn off the cabs currently, and the ones we are removing are blown I think from lightning.

Is there anything I can do to protect these speakers? I thought about putting a switch in but that wouldn't protect me from lightning through a ground only a surge from the hot.
 
Re: lightning protection for powered speakers

Ben Gingerich said:
I have a church install where they want to hang some powered QSC MD cabs from another campus in their building 30ft up, there is already power run up there and there is no way to turn off the cabs currently, and the ones we are removing are blown I think from lightning.

Is there anything I can do to protect these speakers? I thought about putting a switch in but that wouldn't protect me from lightning through a ground only a surge from the hot.
Click to expand...
Lightning is going to go anyplace it feels like.

A switch is not going to stop it.

Think of it this way-if it can jump between the clouds and the ground-do you think the small distance in switch contacts is even going bother it?

What makes you think the current speakers were blown from lightning? I am not aware of any case of lightning hitting a facility (Yes I have seen it lots of times) but have never had a speaker damaged because of it. But that does not mean it can't happen.

As far as turning the cabinets on and off-various manufacturers make remote power relays that turn the power on and off to an outlet. some use a closed contact-other a switched voltage and so forth. SO you need to run a mic line up to the outlet location and back to somewhere people can operate it.

I guess the first obvious (or not) question is-is the pattern-output capabilities etc of the proposed speakers correct for the room? If not-then the whole thing is an excersize in a waste of time and money.
 
Re: lightning protection for powered speakers

Hi Ben,

My understanding is exactly as Ivan's - lightning will go where it wants to go.
To lightning, a tall, wet tree in a storm looks about as good as a lightning rod on top of a steeple.

You can somewhat protect equipment from line surges from nearby lightning strikes.
How effective the protection is depends on the lightning intensity, how close the strike is, what else is dissipating that energy, etc.
SurgeX is a good product for protection from line surges.

Thanks and good health, Weogo
 
Re: lightning protection for powered speakers

Lightning hit the steeple of a church where I'd done an install. It took out the phone system, the alarm system and all the computers. It didn't touch the sound system or the kitchen.
 
Re: lightning protection for powered speakers

Ivan, I was deployed for a few weeks and when I came back was told it was after a storm they had their center cluster out in their main gymitorium and the main LR in their youth center. (2 different buildings)
Yesterday I used a vibroground and found the resistance to their electrical ground was less than stellar, over 80ohms. So in my understanding if lightning was even close it could cause issues even if grounding was good and raises that possibility if its poor.

My thought with the switch was all that your moving when you flip that switch is the hot, nutral and ground are still connected, therefore not adding protection from a switch.
I guess I'm looking for something to be added between the outlet and the speaker that will blow up first that's small enough to be safely mounted that high.

They are starting an addition in the fall and will put a new danley system in as a part of that. (Designed and installed by a reputable company that I work for occasionally)
Coverage and output of the MDs is pretty ideal for the current room and material, other than the need for some frontfills.

Thanks weogo
 
Last edited:
Re: lightning protection for powered speakers

Ben Gingerich said:
My thought with the switch was all that your moving when you flip that switch is the hot, nutral and ground are still connected, therefore not adding protection from a switch.
I guess I'm looking for something to be added between the outlet and the speaker that will blow up first that's small enough to be safely mounted that high.
Click to expand...

I was called in once to fix a system in a store where lightning hit the outside neon sign, blew it up, then jumped almost a FOOT to the nearby speaker wire, toasted every speaker on the line, burned the wire for about 100' leaving scorch marks along the drywall where it was stapled and bigger burn marks near every metal stud, burnt out a wall mounted volume control, and also took out the amplifier which was after about another 100' of wire, and on another floor, and in an IT room where everything else was fine.

The point is: Lightning will jump through/across/around a switch or any other protection device like it's not even there.. most protection devices are to help with surges etc caused by lightning strikes somewhere else.

The only way to literally protect your equipment from lightning is to provide a better place for the lightning to strike (ie: lightning rods)

PS: if there are no burn marks, I would suspect you had a surge, not a lightning strike..
Jason
 
Re: lightning protection for powered speakers

Jason Lavoie said:
I was called in once to fix a system in a store where lightning hit the outside neon sign, blew it up, then jumped almost a FOOT to the nearby speaker wire, toasted every speaker on the line, burned the wire for about 100' leaving scorch marks along the drywall where it was stapled and bigger burn marks near every metal stud, burnt out a wall mounted volume control, and also took out the amplifier which was after about another 100' of wire, and on another floor, and in an IT room where everything else was fine.

The point is: Lightning will jump through/across/around a switch or any other protection device like it's not even there.. most protection devices are to help with surges etc caused by lightning strikes somewhere else.

The only way to literally protect your equipment from lightning is to provide a better place for the lightning to strike (ie: lightning rods)

PS: if there are no burn marks, I would suspect you had a surge, not a lightning strike..
Jason
Click to expand...
I got called to a local church that got hit by lightning.

When I got there-the phone company-alarm company-computer company etc was there.

There were burn marks that came through the drywall all over the place.

It took out most systems in the Church.

HOWEVER the only thing that had an issue in the sound system was the choir mics (hanging from the ceiling) were bad. The speakers were also hanging from the ceiling-and they were fine.
 
Re: lightning protection for powered speakers

Ben Gingerich said:
I have a church install where they want to hang some powered QSC MD cabs from another campus in their building 30ft up, there is already power run up there and there is no way to turn off the cabs currently, and the ones we are removing are blown I think from lightning.

Is there anything I can do to protect these speakers? I thought about putting a switch in but that wouldn't protect me from lightning through a ground only a surge from the hot.
Click to expand...

The only reliable way to protect against lightning damage is to provide a safe low-impedance path for the lightning to follow. There are many ways of achieving this, but MOVs and other surge-protective devices typically aren't a major component. Heavy-gauge stranded wire, on the other hand, typically is.
 
Re: lightning protection for powered speakers

We have had a number of churches struck by lightning (upper Midwest). From memory, nothing behind SurgeX has had any sort of issues. Agree that lightning rods/path to ground are essential in addition to whatever the power sequencing/protection system entails.
 
Re: lightning protection for powered speakers

Caleb Dick said:
We have had a number of churches struck by lightning (upper Midwest). From memory, nothing behind SurgeX has had any sort of issues. Agree that lightning rods/path to ground are essential in addition to whatever the power sequencing/protection system entails.
Click to expand...

I'm originally from the Mid-west right off the Mississippi River, and the company I worked for used Furman stuff on everything and would never install powered speakers because there was no way to protect them. It seems like powered cabs in an install would be great for someone who doesn't know what they are doing if they have the electrical issues worked out.
 
Re: lightning protection for powered speakers

Ivan Beaver said:
What makes you think the current speakers were blown from lightning? I am not aware of any case of lightning hitting a facility (Yes I have seen it lots of times) but have never had a speaker damaged because of it. But that does not mean it can't happen.
Click to expand...
I've seen it happen.

The electrical service of a club on a lake received a direct lightning hit and it destroyed the electrical panel and a lot of the gear that was directly attached to it. However, the power amplifiers came through completely unscathed (Crown CT-800's and CT-1600's). However, every driver that was attached to these amplifiers had to be reconed or replaced. Every single one had a melted voice coil from the lightning strike. This says good things about the capabilities of those old Crown amplifiers. :lol:
 
Re: lightning protection for powered speakers

Josh Millward said:
I've seen it happen.

The electrical service of a club on a lake received a direct lightning hit and it destroyed the electrical panel and a lot of the gear that was directly attached to it. However, the power amplifiers came through completely unscathed (Crown CT-800's and CT-1600's). However, every driver that was attached to these amplifiers had to be reconed or replaced. Every single one had a melted voice coil from the lightning strike. This says good things about the capabilities of those old Crown amplifiers. :lol:
Click to expand...

Or the serendipitous nature of lightning...
 
Re: lightning protection for powered speakers

Dick Rees said:
Or the serendipitous nature of lightning...
Click to expand...
For sure!

Recently assessed lighting damage at friend's house.

He has a lightning rod, but the lighting decided not to use it, took out two phones (phone lines were OK) a internet receiver and the router and one computer hard wired to it.
A GFCI outlet outside near where they saw the lightning flash was the likely point of entry, it showed scorch marks between the neutral & hot and the foam lined cover. The GFCI was dead, and the motion sensor light nearby was stuck in the "on" position.

Two out of the 9 the light fixtures on his porch, all on the same circuit (through a dimmer that was stuck full on, but still worked as a switch) still worked.
I expected to find burnt bulbs or a burnt open wire, but instead found one wire nut connection (out of nine) had stopped passing current.
After loosening it and putting it together it worked fine, there was no visual indication whatsoever why it would not pass AC before being opened.

He found a few days later his deep well pump also was dead...
 
Re: lightning protection for powered speakers

A few years ago a swimming pool outdoor music system install I did took a fairly direct hit one night. Both Crown CTS amps were toast and the about half of the connections on the terminal blocks for the speaker lines were burnt / carbonized just enough not to pass signal. All the drivers in the Community R .5's around the pool were fine!

Just today I was working at a church that was complaining about noise in the pulpit and lectern mics. Both of the mics were producing considerable frying sizzling sounds, they still did pass audio. Telling them it was odd that two mics have the same problem they said it happened after the building took a direct hit that took out various other things in church as well.
When it happened the sound system was confirmed to be powered off. Nothing else in the system has shown any signs of trouble.........yet!!!

Depending on the path of entry and how direct the hit is I think it's safe to say there is no such thing as 100% lighting proof protection.

Since were on lighting protection what are your thoughts on doing an indoor show when there is a pounding thunder storm right on top of were your working.
 
Re: lightning protection for powered speakers

Mike Caldwell said:
Since were on lighting protection what are your thoughts on doing an indoor show when there is a pounding thunder storm right on top of were your working.
Click to expand...
Of the 238 lightning deaths in the USA between 2006 through 2012 nearly all occurred outdoors, statistically there is a greater chance of being killed by a vehicle smashing through the building than being killed by lightning indoors. I don't worry much about either from a safety standpoint when indoors.

The potential for equipment damage from a lightning strike is of course possible, but given the random nature of lightning I'd be no more inclined to shut down an indoor show than I would be to run around unplugging every appliance in my house when I hear thunder.
 
Re: lightning protection for powered speakers

I seem to remember once upon a time being told about some crazy idea to pass the amp to speaker cables through a neon tube for over current protection. Just curious if anyone else has info on that insanity. The idea is that if it gets too loud it'll either glow brighter or blow, I think.
 
Top Bottom