Light bulb question- running a 120 volt bulb at 30 volts- watts reduced by 75%?

   / Light bulb question- running a 120 volt bulb at 30 volts- watts reduced by 75%?
  • Thread Starter
#21  
   / Light bulb question- running a 120 volt bulb at 30 volts- watts reduced by 75%? #22  
By now you all know that I know very little about bulbs/voltage/resistance. So this bulb could overwhelm the projector power supply? If it has a resistance rating of 14.4 ohms and the factory bulb has a resistance of 11.25 ohms, wouldn't it draw less current than the factory bulb?

Yes, but remember those dynamic effects I mentioned? Light bulbs are NOT fixed resistors. You are going to run a 12 volt bulb at nearly 3 times its rated voltage. It is going to draw some serious current, and it is going to be very bright for a short time. I don't think you are going to have a successful outcome with either of your scenarios. It will be interesting for you to report the results, and I have been wrong many times before, but in my opinion you need the correct bulb and I don't think any of your substitutions will be successful. I think your original substitution will just glow a bit and not be useful, and it would glow into the next century, and I think your next suggestion will glow very brightly for either a few seconds, or perhaps a few minutes. I don't know how your power supply is going to like the second substitution. It may be OK.
 
   / Light bulb question- running a 120 volt bulb at 30 volts- watts reduced by 75%? #23  
What is the bulb model?

Aaron Z
 
   / Light bulb question- running a 120 volt bulb at 30 volts- watts reduced by 75%?
  • Thread Starter
#25  
The bulb I need is a DLD.
 
   / Light bulb question- running a 120 volt bulb at 30 volts- watts reduced by 75%? #26  
   / Light bulb question- running a 120 volt bulb at 30 volts- watts reduced by 75%? #27  
I would think you could find at least a 24V bulb. And get a few for spares, they should take the 30V for a time.
 
   / Light bulb question- running a 120 volt bulb at 30 volts- watts reduced by 75%? #28  
They've made pretty big strides in LED color temperature lately. Incandescents are pretty inefficient, just look at the huge changes in flashlights over the last 5 years.

I have been happy with LED soft white bulbs. I moved all my LED daylight bulbs to the attic, crawlspace, garage, shop, etc.
 

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