Ballasts

Ballasts in hydroponic lighting are required for most grow lights. Fluorescent and LED grow lights don’t need a ballast. But apart from these two types, all others, including HID lights, do need a ballast so that the lights can function correctly.

Many growers will buy a kit with all the necessary components, including the ballast. HID grow light kits are an excellent example of this, and they include everything you’ll need in the same package, such as an MH bulb, HPS bulb, ballast, timer, reflector and hangers.

It’s the ballast that powers the light bulbs. Grow lamps tend to be low-resistance when on, but they need a high voltage to get started, and a ballast provides both of these necessities.

When you switch on a lamp, the ballast gives it a high enough voltage to start the arc. When it first starts up, the sodium within it is solid, but this soon melts and eventually vaporizes.

In its gaseous state, the resistance of the light will drop, and it will need much less power to keep going. A ballast’s presence ensures that the light receives only the minimum current it needs and nothing further. Without the ballast to control the flow of electricity into the bulb, the lamp would continue to glow, increasing in intensity until a point where the bulb explodes.

When first starting up, the standard HID bulb needs more power than the outlet usually provides, so the ballast increases what it gets from the mains electricity to give the light what is required to light up. Once operational, it will regulate whatever it gets from the mains, with variations that sometimes occur, ensuring that the lamp receives a constant and steady source of electricity.

When HID bulbs get older, they need more power to be able to run, a little-known fact. The ballast will automatically look after this ‘ageing’ and increase the electricity to the bulb as it ages.

Then when the bulb reaches the point where it demands too much electricity, the ballast will switch off to prevent an accident from happening. When this happens, you can restart your bulb, but the light’s ballast will soon, and very rapidly, switch it off again—indicating that you need to buy a new bulb.

Magnetic vs Electronic Ballasts in Hydroponic Lighting

There are two types of ballasts in hydroponic lighting, magnetic and electronic, and both have pros and cons.

Electronic ballasts operate at lower temperatures and are more efficient, providing a higher output while using less power.

Most electronic ballasts are dimmable to run low-wattage bulbs and HPS and MH bulbs. But there are some disadvantages as well.

If you’re running a T5 fluorescent light and want to replace the fluorescent bulbs with T5 LED tubes, you may have to bypass the ballast provided within the fixture. Several LED tubes work with the ballast, but you need to disconnect this in many instances for it to work correctly.

In conclusion, ballasts in hydroponic lighting have an essential role, and it’s impossible to run a conventional HID hydroponic grow light setup without one. If you’re a beginner, buying a kit with everything you need, including the ballast, all the cables and a reflector, would be advisable.