strobe lights and explosives
strobe lights and explosives
(OP)
Not sure if this is the right forum- we use 12VDC strobe lights on vehicles , but also have electric detonators in use- someone heard throught the grapevine that the capacitors in strobe lights could cause detonation of blasting caps? I guess same theory as radio tramsmitters on construction sites- am trying to get info on the capacitor used from the manufacturer but no luck yet- Not sure what potential 'power' a capacitor in a strobe light may produce? (sorry the info is limited but it's hard to get it so far)





RE: strobe lights and explosives
I think something may have been changed in the story when you heard it. Radio transmitters are banned from blasting caps because they may transmit a signal to a blasting circuit and cause an unplanned detonation. A capacitor, by itself, won't cause a blasting cap to explode unless it is connected to it.
RE: strobe lights and explosives
Hands-on (actually hands-off preferably) testing could be a blast!
Wonder if there are any formal publications/codes/guidelines for transmitter and device restrictions available.
Wheels within wheels / In a spiral array
A pattern so grand / And complex
Time after time / We lose sight of the way
Our causes can't see / Their effects.
RE: strobe lights and explosives
If it's a problem they should know about it.
RE: strobe lights and explosives
RE: strobe lights and explosives
Analogkid's response points to the issue - what is the RF spectrum radiated from the strobe light? Another question would be how does the spectrum from one strobe light compare to that made by other manufacturers?
One could guess that the RF spectrum is not much different that that emitted from the ignitions system of a vehicle engine. But to be safe you would have to perform some RF emissions tests to determine the energy/spectrum present.
RE: strobe lights and explosives
The way these things usually start is that probably someone did get killed or injured while doing so, and after the fact they could not find out why. So someone blamed it on the one piece of electronics that was there at the time, however unreasonable it might seem. The same was said about cell phones at gas stations, and it turned out to be bunk. The real culprit was found likely to be static discharge from exiting the car, but people were looking for something more complicated than that. Add to that the fact that it is cheaper to ban them than it is to test them and you have the basis for an "urban legend" that begins to affect policy. It's just easier to specify rotating beacons that to do enough testing to satisfy every possible future claimant AND THEIR LAWYERS!
"Venditori de oleum-vipera non vigere excordis populi"
RE: strobe lights and explosives
The pulse transformer is also an RF emitter and as such will need to qualified for HERO - hazards of electromagnetic radiation to ordnance, which is covered by ADS-37A or MIL-STD-464
TTFN
RE: strobe lights and explosives
Extreme long shots..
www.llnl.gov/es_and_h/hsm/doc_17.03/doc17-03.html
www.llnl.gov/es_and_h/esh-manual/volume2.html#s17
www.logicsouth.com/~lcoble/dir5/explosiv.txt N.B., 24.09
One issue—for the given environment, are the detonators safer with leads shorted or unshorted?
RE: strobe lights and explosives
I remember we made something that was going into a mine. We had to put resistors in series with all of the capacitors so that if the circuit ever shorted out, the current wasn't high enough to initiate an ignition spark.
RE: strobe lights and explosives
what you trying to do give someone the s..ts ?
Rugged
RE: strobe lights and explosives
RE: strobe lights and explosives
Operahouse- changing the detonators is not an option
ruggedscot- depends..
While I was researching the use of RF equipment for underground I did come across this site- surprising what may set off an electric detonator& why
www.nclabor.com-osha-etta-indguide.ig11.pdf
Thanks for all the resopnses- I know one major company has removed them from service until more research done-rotating beacons I think are the answer in the meantime
RE: strobe lights and explosives
RE: strobe lights and explosives
What is really being asked is, can a strobe circuit couple enough energy into a nearby adjacent circuit to be dangerous ?
There are two issues, the energy available, and the efficiency of any coupling medium. The energy available in a vehicle strobe is not going to be very high, I do not know a figure, but my guess might be around 100 millijoules per flash, realistically about the same power as the discharge of an automotive ignition coil.
To couple energy into another circuit requires either magnetic, capacitive, or electromagnetic coupling. A vehicle strobe is a compact device without any large current carrying loops, or large flat exposed plates carrying rapidly changing high voltages.
A radio transmitter with antenna is DESIGNED to radiate RF energy and is going to be dangerous. Something of equal power with no functional antenna is going to be pretty harmless.
If you are worried, take a strobe around to the nearest EMC laboratory and get them to test it for various types of RF emissions. Get a written report, and ask their opinion.