Metal Halides: DE vs SE

If you put a 400 watt bulb on a 250w magnetic ballast, you WILL have issues. Test your amperage draw, it will be substantially more than 250 watts of power... This would overdrive your ballast, not the bulb.
This would be a different case if you have an electronic ballast though....
just my $.02

 

an hqi ballast is meant to run de bulbs. It takes more to fire a 400 watt de bulb than it does a se bulb. This is why a se 400 watt radium se bulb will go fire to the full on an hqi ballast. Thus underdriving the bulb and extending the life of the bulb and burning less electricity. If you try to run a se bulb on an hqi ballast you will overdrive it thus shortening the life.

 

... it doesn't take more. There are just two different methods to fire bulb. Pulse, and probe. True HQI's use pulse, and most SE's use probe. Pulse use ultra high voltage(not amperage) to ignite gasses in bulb. Probe is built INTO the SE bulb itself, and ignites the bulb then 'disengages'.

In theory, what you're saying just does not make sense to me. Perhaps it will work, but I don't believe it'd be under driving anything.

 

read this

http://www.3reef.com/forums/reef-lighting/400w-mh-advice-needed-69013.html

 

Here's the thing though...
Bulbs don't TAKE the power they are given, they DRAW the power they require.
I cant take a bulb and go, here you go... You're on a 20 amp 110 volt house circuit... burn at 2200watts!
I've tried running a 250 bulb on a 175 ballast, and the ballast drew near twice as the "specified" amperage. Might work short term, but that ballast is sure working over time.

If you read his explanation, his calculated "wattage" which would be 201watts/110volts=1.82 amps was for the correct bulb. I'm betting the bulb was receiving the full 175 watts, no more or less. That other 26 watts is the heat lost in the ballast itself due to inefficiency.

Also, a M137 ballast is a pulse ballast... pushing a probe start SE bulb would greatly REDUCE the bulbs life. There are pule start SE bulbs though.

In contrast, notice how light sockets will specify "max wattage bulb" on them... The electrical cord has nothing to do with how many watts the bulb will pull, the bulb itself will bulb what it's supposed to.
The warning is there to protect the cord itself(and the fixture)

 

Whatever the end of the arguement of the DE needing more startup current to fire (which I agree) compared to SE bulbs, I like SE bulbs being encased in UV shielded housing over the bare bulb of DE makes. I noticed last night that a section of my DE bulb UV protection was slightly open. I recently had a problem of my maxima clam releasing his byssal threads from its rock and had no clue as to why. I closed up the area that the UV shield and metal meet and this morning my clam was reattached to the rock. I'm starting to really dislike DE bulbs now for the UV exposure potential.

 

+1
Thought someone had mentioned this already. I believe it's just quartz that accomplishes this, also helps facilitate bulb changes

 

thanks for all the info guys, keep em coming