Magnetic ballast question.

[Anonymous]

So what's the primary function of the capacitor in a MH ballast? Reason I ask is that I'm lacking a spare capacitor that fits specs, 10 microfarad, 400v, I do however have a 25 microfarad capacitor but if it's going to make the ballast go squirlley I'd rather not go that route.

 

[Ben1]

I thought these were the kind of questions you answered sfsu! :lol:

 

[Anonymous]

I need to confirm it, but the capacitor in the ballast circuit is called ignitor, and it purpose is to generate enough voltage and current with the transformer to fire up the bulb. Once the current starts to flow, the capacitor shuts down, and the coil/transformer acts to limit the current going thru the bulb so that it won't burst up. The capacitor need to match with the coil for it to work properly, so you really need to get your EE-101 to calculate rather you can switch it with something else without making a "mess." I suggest you PM Tom Burn on this issue....

 

[Anonymous]

Ben: Physicists/Astronomer not Electrical Engineer

Dupa: When there is no ignitor on this setup, those are for HQI setups IIRC, but yeah I figured it had to do with regulating current, since my bulbs with the faulty capacitors only pull 120-130watts (175w ballast), however with a replacement they pull 190-200watts. But I figured it was a lost cause trying to flip it out, just a 10 microfarad capacitor rated at 400 volts isn't something that I can swing by home depot to pick up.