Re: generator math help

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its goofy.   CFL are so much worse then any tungsten bulb will ever be life to death.  Well unless Mercury has some how become good for the environment.    As for dealing with Mains.   Father and brother are electrical engineers and uncles are contractors.  
In the US we have both 3 prong grounded (for things that are self conducting like metal power supply in a computer or metal toaster etch) and 2 prong grounded.  Well 2 prong Neutral and hot.    In all cases Neutral is grounded  at the box if its wired right.     


FYI I lived in OZ for a year at the VFX sup for a company in Sydney. 

Randy S. Little
http://www.rslittle.com
http://www.imdb.com/name/nm2325729/




On Sat, Jun 15, 2013 at 1:39 PM, karl shah-jenner <shahjen@xxxxxxxxxxxx> wrote:

Karl.  This is not meant so sound like disagreement.  Just trying to get a
full grasp on benefits vs draw backs.        Ok We we are using a tungsten
bulb in line (soon to be illegal or expensive in the US.)     How well will
this work with other types of bulbs?

I would suggest only resistive load bulbs like the tungsten lights.  Most of the others that come to mind have circuits in them  that behave inappropriately for the purpose.  Sounds like the US is going the path we went down of banning old style globes but here floodlights (100Wand higher), heat lamps and special purpose bulbs like those found in ovens, fridges anb such are still legal.  In the EU I understand tungsten globes were banned too, but a clever person started selling them as 'small room heaters' .. of course here our legislators clutched their chests and immediately sought to prevent this workaround .. stupid really, the rush here to be all green pushed us to use the stupidly expensive compact fluorescents, you guys will probably have good LEDs before any bans come into place



other then being limited by very low
watts.

Second not having much generator experience.   Do I need to worry about
spikes that can damage the packs to want this resistor set up?

no, that's the beauty of it :)  Your generator isn't 'pushing' power, your flashes are 'drawing' - the threat is drawing too much too fast for the generator... capacitors suck =D  'resisting' the draw won't hurt the flashes one bit, it's perfectly fine for them and probably better in the long run, the bit that can take damage in this scenario without protection is the generator.  So by putting a resistive load of a low wattage in-line you're creating a current limitter which prevents the flashes drawing too fast. Tungsten also has a limited but functional ability to smooth the load, as current and resistance are affected by the temperature of the globe in a good way.




What
type of light fixture are you using that works inline of a heavy gauge
extension cable.  Im not keen on cutting one open until I have lots of
info.   They are kind of pricey.

I would make up a box with a lead passing through a grommet on one side and a wall plug on the other side, with an edison socket (we use bayonet mount globes in Oz) mounted either inside or out and wire it internally, that way it's just a few parts.  part sources I couldn't suggest, I tend to save junk and salvage bits as needed.. but actually, thinking about it - if you had an a cheap or old table lamp or such, you can get the socket and a plug from that, then you just need a female socket like a wall plug froma hardware store.  see below for mangled description for wiring this*

Also you won't need a heavy extension, by way of example we use 240 volts here and our smallest, cheapest extension cables are 10 amps, for 2400 watts maximum.  But presume I set up such a cable with the intention of using only up to a 100W globe, the maximum current I would use would be 0.4 amps so the wiring really only need be rated to that (I'd still give myself an overhead, but clearly 10 amp is excessive).  now if I only put a 20 watt pilot globe in my lamp box, I'd be limiting the current to a mere 0.08 amps!

this can help with calcs: http://www.supercircuits.com/resources/tools/volts-watts-amps-converter


*
actually dear readers, unless you're familiar and experienced with mains power PLEASE do not fiddle about with this unless you know what you're doing or are happy with being zapped.  I rarely get zapped but I'm one of those people that doesn't drop dead when I get a belt, just burns and some charring.  Not everyone is as badly wired as me and normal folk are not supposed to survive electrocution.

I'm not sure if you guys always have earth wires in your AC leads, we do for most things and I tend to like keeping them for obvious reasons!  Presuming you do, just make sure the earth is intact on the plug to the body of the box (connect it to any metal chassis or part of the box that fingers may touch) and then out to the wall plug on the other side of the box

take your table lamp or shed light or cheapie outdoor floodlight and leaving the plug (male) end alone, cut one wire close to the bulb socket  (call the cut ends A and B) - leaving a short lead that you will attach to one outlet on the wall socket (A).  the long length (B) that remains attached to the wall plug is now connected to the other outlet of the wall plug.  that's pretty much it!  As you can see power comes out the wall plug, goes into the bulb and out to a wall socket, the other lead completes the circuit when you have a bulb inserted and something plugged in to your wallplug.  All you need now is to stick it in a box.

If you box it then run the lead with the plug through a grommet (so you don't sever the wires against the box), mount the bulb socket and wall plate to the box -  check everything is insulated, secured and earthed then have your least favourite relative try it out.






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