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Lightning Strikes

Published : 9th November 2004

Be advised that some genny owners do not allow lightning strike units on their genny's. Be sure to ask first if you go that route. I got bit once when we were set to go and the genny owner pointed to a sign on the Genny that said "No Lightning Machines".

At least that's my experience here in NYC.

John Roche, gaffer
NYC


The only way to be sure that the Lightning Strikes won't effect your other conventional lighting is if the box you're tying into is on a separate transformer for the building. I would guess it probably is not. Therefore you should probably get a generator. Also consider using the 50,000 watt instead if you do use house power.

The 100A fuses won't burn right away with a 175A surge--but they will wear down and eventually and blow. The 250A boxes at the club probably are providing power to other equipment as well, so you may not be able to count on having 250A available on those boxes.

Michael Ambrose
Gaffer--L.A


I would suggest using the Lightning Strikes Battery Packs. I always spec them with Lightning Strikes Heads as you never need to worry about local power draw problems or freaking the gennie out. It only takes a 16amp feed (@240 volts as supplied here in the U.K.) which trickle charges the batteries while the head is not striking. It also means that you can position the head way away from set, (usually where the D.P. wants it), without that big thick cable run!

Give the guys at Lightning Strikes a call as they are always very helpful.

Hope this helps . . .

Joshua Breckeen
Gaffer, U.K.


>Be advised that some genny owners do not allow lightning strike units >on their genny's.

Errrr, sorry John. That may have been my doing years ago when I took out a 1200A genny using the old-style, welding rod, lightening machine.

First strike put it right out of commission. Took a few hours to get a replacement on a music video for Mariah Carey. Opppps!

The posted sign appeared shortly thereafter.

Jim Sofranko
NY/DP


If you can't get or afford the accumulator packs for the lightning strikes, I would definitely suggest a separate generator.

The first time you plug the strikes in fire them, stand near the gene. The surge current is impressive and the generator reacts as though you applied a dead short to it ..to this regard many generator hire companies ban them due to the possibility of blowing up the AVR electronics.

I would often have the production company hire a Generator that was just residentially silenced, from a building construction supply hire company. As the construction industry wasn't familiar with lightning strikes.

I now always get the accumulator packs...which just plug to a domestic general purpose power outlet and charge the accumulator like a begular battery charger.

More weight with the accumulator but you don't need a generator.

Graham Rutherford
Gaffer
Australia


John Roche writes :

>Be advised that some genny owners do not allow lightning strike units >on their genny's...

Probably something to do with having their AVR's (Automatic Voltage Regulators) fried by the massive current demands.

Just out of interest. Does anyone know if the Lightning Strikes strobes use a single diode or bridge in series with the tube, or is it just fired directly across the mains supply? The biggest strobes I deal with are the fairground style units that use a slimmer tube (XOP-25). These use a stud diode in series with the lamp purely because they require a voltage multiplier to raise the standby voltage to about 500V across the tube. Their peak cycle current is a mere 80A.

Graham Rutherford writes :

>The first time you plug the strikes in fire them, stand near the gene. The >surge current is impressive and the generator reacts as though you >applied a dead short to it

With the currents involved, even a modest length of heavy cable probably has a major limiting effect on the current. I don't know if there is a recommended minimum or maximum length of cable run for these strobes, but a modest run could limit the current to less volatile levels.

Clive Mitchell
http://www.bigclive.com


I cooked a genny with 'em too in NYC on a music video!

One phase gets a surge and the genny starts snorting for air like a wounded elephant...not good for rental house relations.

Hard wire or accumulator will solve this problem.

Nick Hoffman
NYC DP


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