Electronic Ballast or Magnetic?

[cmack]

Would you use Electronic or Magnetic ballast for MH? I'm thinking of 250W HQI Bulbs
Magnetic is cheaper, but what are the Cons of Magnetic compared to electronic?

 

[buzz]

I use electronic ballasts for my 2 - 250w MH's.
I think the biggest difference is in their efficiency. Electronic ballasts will save you money on your electric bill.
I have seen both, and I also think the heat generation is less in electronic ballasts. Some may disagree.
The ballasts I have are also half the size of other magnetic ballasts I have seen, which is nice if you are mounting them on top of your canopy.

 

[fender]

Buzz is right.
Efficiency.
You either pay up front for the electric or later with the magnetic but you do pay.
Having said that....
Some tests have shown some magnetic ballasts to drive the bulbs better, but I would only worry about this if you are die hard about it.

 

[bigmac]

The main thing is the heat. The E ballast produce less heat. That's the good thing. They tend to under drive the bulbs so you save a little on electicity but the lights aren't as bright... I wouldn't use one if it was free.

 

[gatorcsm]

bigmac is absolutely right on... They take less power because they put out less power.. Kind of a no brainer. It's like turning down the light to save energy...
If you want the light, go with the conventional ballast. The heat is not that bad, just don't put it in a pile of cloth or newspaper and you should be fine!

 

[gollus]

the electronic ballasts are still more efficent. All that heat is comming from something, and it is comming from extra energy lost in the process of switching the power around so it will drive the bulbs. It is more than just more power out = more power in.

 

[gatorcsm]

You're right, a core design is much less efficient. That wasn't bigmac's point, or mine.
I did some searching on this topic, and you really can't get a straight answer. If you look up a company that sells electronic, it's electronic over magnetic, and vice-versa.
Anyone here done any testing with current in, current out, power factor, etc.
Obviously a magnetic is very inductive, so it has a low power factor, maybe .7 or .8, but it might indicate that the electronic would have a higher power factor, above 1.0, due to it being capacitive. Numbers I've seen have indicated magnetic ballasts around 88% efficient, with electronic around 93..

 

[sebae0]

i know this is a dumb question but how is electronic more effecient if its 250w both ways? the way i see it is 250w in 250w out same bill no matter what? please help me.

 

[gatorcsm]

Wire has a resistance to it, and there is a lot of wire in a magnetic ballast.
There is a transformer, which is a large coil of usually copper wire. I2R losses, or the heat production from the resitance of the wire losses power to perform this function... Therefore, some of your power is going towards producing heat, and never makes it to the light, or whatever component it might be going to.
So if you have 2 250w devices, one is magnetic, the other electronic, the one that is magnetic might put of 20w of power in heat, and the electronic only 10w, since there still is heat production on the electronic devices.. You computer is a perfect example.

 

[fishfood]

From my reading the Electronic ballast will also extend the life of the bulb. I asked the question before about lifespan and was told that my 250DE MH would have a life of about 10 months on magnetic and 16 months on electronic. If this is the case you are saving money in bulbs as well.

 

[sebae0]

thanks for clearing that up for me guys and i agree with kip on the intensity issue.

 

[gatorcsm]

With regards to the expense: This isn't a cheap hobby.. Might as well let the light shine down for all the energy it can draw from the power co.

 

[cmack]

i would rather have 10 months of optimum intensity than 12 months of subpar
Is electronic performance really Subpar? Seems allot of people use the electronic, and their coral look great, and seem to thrive. If the difference in efficiency for example (88% and 93%) is that small, than wouldn't the difference in bulb intensity only be that small also?

 

[fishfood]

You also have to take into consideration what bulb you want to use before you buy the ballast. Some bulbs will not run on certain ballast, and if they do they aren't being used efficiantly. Here is a thread discussing different MH ballasts:MH Link
and one on different bulbs with the ballast:
Bulb & Ballast
So yes you do get more PAR out of the magnetic ballast. I've seen tanks were people are able to get just as nice color in SPS under electric powered ballast.

 

[bigmac]

Originally posted by Fishfood
From my reading the Electronic ballast will also extend the life of the bulb. I asked the question before about lifespan and was told that my 250DE MH would have a life of about 10 months on magnetic and 16 months on electronic. If this is the case you are saving money in bulbs as well.
That's one thing I can say isn't true. I ran 250 watt DE's for 16 months on a true HQI mag ballast, they could have went 6 months longer with no problem. This is one case where I'm about 90% sure the electronic ballast is a waste of money. There's no way it can come close driving the DE bulb as well as the mag ballest. Sure, you might save a few pennys on power and in 3 or 4 years you'll get youre money back for the extra cost of the e-ballast but you'll never drive the bulbs to their potential.