Experienced Electrician here to answer any and all Growroom ELECTRICAL QUESTIONS

What are the major differences between magnetic, electronic, and digital ballasts; and which type would you suggest using? Thanks.

First off, you should know what a Ballast does. The whole purpose of a ballast is to limit current, because gas discharge bulbs won't limit current themselves (they look like a negative resistance), and will just eat up current until it destroys itself, or the breaker/fuse goes.

Magnetic Ballasts have a poor power factor, that is, there is slight power loss when in use, they also have a slow switching speed, the mains frequency 60Hz (50Hz), which you hear as a humming noise. Newer magnetic ballasts have capacitors to correct the power factor so there isn't as much of a loss, but the hum is still there.

Electronic Ballasts work like your computer power supply, they switch at incredibly high speeds, usually 20kHz+. These essentially take the AC, turn it into DC, then turn it on/off really fast.

Digital Ballasts are just fancy Electronic Ballasts that have extra options like preheating the cathodes for rapid starting, or being able to dim the bulb.

Personally I would say get an electronic ballast, if you can get one that has rapid starting capability get it, if you can get one that instead has programmed start capability, get it instead. Programmed start is like Rapid Start, but will prolong the life of the bulb a bit more.

What about durability, and performance over the lifetime of the ballast?

Electronic Ballasts are all solid state, that it is all integrated circuits and such, I would think these would last longer than a Ballast with large magnets, inductors and capacitors. Also, the magnets in a magnetic ballast will heat up, and heat kills magnets, so it will be its own downfall.

As for lifetime of the bulbs, using an electronic ballast will make it last longer, especially if you get one of the programmed start ballasts. Performance wise, an electronic ballast will win out, the magnetic core of a magnetic ballast will eat power as I said before, that power will be not getting to the bulb.

Originally Posted by Atarijedi

Electronic Ballasts are all solid state, that it is all integrated circuits and such, I would think these would last longer than a Ballast with large magnets, inductors and capacitors. Also, the magnets in a magnetic ballast will heat up, and heat kills magnets, so it will be its own downfall.

As for lifetime of the bulbs, using an electronic ballast will make it last longer, especially if you get one of the programmed start ballasts. Performance wise, an electronic ballast will win out, the magnetic core of a magnetic ballast will eat power as I said before, that power will be not getting to the bulb.

I agree with atar, he pretty much nailed it. I would go Electronic just because replacement parts are easier and cheaper to come by.

The room im using as my grow room was built by the previous owner of the house. it has two wall sockets on one side and a single socket directly across the first two. They are standard wall sockets, 15a 120v? The previous owner mentioned that the two together share the same power cable through the wall and the stand alone uses the same cable as the light bulb. My plan was to hook up 3 1000 watt hps lights in there, one for each socket but im concerned that it may be too much for the single cable inside the wall. What do you think?

I'm running a 1000W/MH, in an area that wasn't originally intended for such a purpose. I'm a bit sketchy about going over the limit on the power after lighting, the hydro kits, and ventilation that I setup. Am I just worrying? If not, what is it I need to do to remedy this issue?

Originally Posted by Snicklefritz

The room im using as my grow room was built by the previous owner of the house. it has two wall sockets on one side and a single socket directly across the first two. They are standard wall sockets, 15a 120v? The previous owner mentioned that the two together share the same power cable through the wall and the stand alone uses the same cable as the light bulb. My plan was to hook up 3 1000 watt hps lights in there, one for each socket but im concerned that it may be too much for the single cable inside the wall. What do you think?

If you are planning on using (3) 1000w HID in that room you will HAVE TO run a dedicated line in there. You are going to pull at least 3000+ watts and you will overload those circuit pretty much right away.

I would suggest running 2 new circuits from your panel (a 12/3 romex cable). A 12/3 romex has 2 circuits in one cable. This way you have plenty of wattage capacity to run your light and other equiptment like fans, pumps, timers... Good luck, let us know what happens.

Originally Posted by beauser420

I'm running a 1000W/MH, in an area that wasn't originally intended for such a purpose. I'm a bit sketchy about going over the limit on the power after lighting, the hydro kits, and ventilation that I setup. Am I just worrying? If not, what is it I need to do to remedy this issue?

Usually, in a middle class home, bedrooms are ran off a 15 amp circuit. Most of the time, the bedroom has its own circuit but if it is shared with other bedrooms you are more then likely going to overwhelm the circuit.

If you can, I all ways recommend running new, dedicated circuits for your growing needs. Just because its peace of mind that your not going to trip vital circuits.

Add up all your equiptment you plan to use and use this formula. Amps = watt / voltage.

Example. Normall household voltage= 120v So, 1200w / 120v= 10 amps