Electronic vs. Magnetic Ballasts – Buying Guide
Commercial grow lights are not your grandfather’s light bulb. They are highly sophisticated components with very specific energy needs that if not met, can have a negative impact on their longevity and ability to provide adequate PAR to your cannabis plants.
Enter the lighting ballast. The purpose of a ballast is to limit and regulate the amount of current being sent to your grow bulbs to help maximize the lamp’s life and light output. An electronic or magnetic ballast is like the CPU of a computer – without it, all you have is an expensive paper-weight.
Lighting Ballast Breakdown
Before we jump into how to shop for ballasts, let’s take a look at the three primary types. Magnetic ballasts, electronic ballasts, and LED drivers. Once we cover the basic knowledge surrounding these 3 types, we’ll talk about how to shop for the best ballast for your cannabis cultivation business.
Magnetic Ballasts (MB)
Some times, the old ways are the best. Magnetic ballasts are long known for their reliability and durability. Magnetic ballasts have very few parts that can break down compared to electronic ballasts. Most times, MB cost less. This makes them attractive to new growers.

MB are often more affordable than their electronic counterparts, however the cost of electronic ballasts are dropping. One of the better known characteristics of MB, especially among experienced cultivators, is that they don’t produce radio-frequency or electromagnetic interference. (More on “EMI” and “RFI” later)
Electronic Ballasts (EB)
The electronic ballast is truly a feat of engineering and allows your grow lamps to shine how they were intended. EMs have some significant advantages over magnetic ballasts, as well as a couple disadvantages.
Electronic ballasts eliminate the “hum and flicker” often associated with magnetic ballasts. This is because EMs operate at a much higher frequency than MBs. Other advantages of EMs include:
- Much more energy efficient, saving money in utility costs
- Nearly no hum or flicker
- Grow bulbs last longer due to the more consistent power delivery
- EMs can often operate multiple lamps, reducing the number of ballasts needed
- Increased light efficiency, bulbs burn brighter, longer
- EMs weigh less than magnetic ballasts allowing more flexible installation options
That said, probably the biggest concern for cannabis cultivators using electronic ballasts is the radio-frequency interference they emit (RFI.) This can cause disruptions with electronic equipment and cellular reception.

But the greatest concern is that a large grow facility using electronic ballasts can be found and identified easily by law enforcement. We are assuming you are operating a legal greenhouse, however unexpected visits from local authorities can be inconvenient at best.
Newer electronic ballasts are shielded to help reduce the amount of RFI being transmitted, however it’s always a concern for (especially) newer cultivation businesses.
LED Drivers
Ok, you caught us. LED drivers are not ballasts. The reason we wanted to include them into this discussion is because they serve the same function as a ballast for LED fixtures. There are, however a couple key differences.
The job of a ballast is to regulate power from your main line to your grow lamps. LED drivers accomplish this, however they also convert the AC current into DC. (Alternating current to direct current.) – You’re smartphone charger does much the same thing, converting your standard 120 AC into DC at the proper voltage.

Many LEDs such as “plug and play” models have their driver built in and can be compatible with existing ballasts. Others use a remote driver, daisy-chaining several LED lamps together.
When replacing fluorescent grow lights with LED’s, there are three options:
- Type 1: “Plug and Play” linear LEDs – Designed to work with current ballasts. LED driver will convert AC coming from the ballast into DC power. Always check for compatibility first.
- Type 2: Ballast Bypass – Installs into the current voltage being sent to your electrical sockets. Ballasts must be removed. The LEDs driver is sufficient.
- Type 3: Complete Lamp and Ballast replacement – existing ballasts are replaced by an LED driver. Fluorescent lamps are replaced with LED lamps.
The option you choose depends on how much time, money, or both you are willing to invest into your grow lamp upgrade process. A full exchange of hardware (Type C) can be a bit more complicated, however it provides maximum flexibility and allows a cultivator to take full advantage of all the benefits LED grow lights have to offer.
How To Shop For Ballasts
Now we have some clarity on the primary types of ballasts and LED drivers you will run across as you look to build or expand your cultivation facility.
Next, let’s break down some of the steps and questions you’ll want to ask yourself before making a decision on which type of ballasts you’ll need to purchase.
Assess Your Situation and Choose a Strategy
Before you decide to purchase new or replacement grow light equipment, take the following into consideration:
- New or Existing? – Are you building a new greenhouse or refurbing / expanding a current greenhouse?
- Budget – Do you have the funds to augment or upgrade your lights, ballasts, fixtures, and reflectors?
- Personal Preferences – do you already have a preferred lamp type? Do you want to look into the latest LED technology, or are MH and HID lamps your gig?
- Interference & Light Flicker – Are you concerned with RFI / EMI drawing attention to your grow operation? Do you want to avoid humming noises and lamp-flicker?
New or Existing?
If you are looking to replace a worn ballast installed in a current grow facility, your easiest option is to simply replace it with a similar-style ballast. For older or more traditional grow room, it’s likely your ballasts are magnetic – so always check to be sure.
When building a new grow room, you have the advantage of deciding how you would like to take advantage of grow light technology. You may want to start with the tried and true magnetic ballast, or give your cannabis plants the best start by installing electronic ballasts, known for higher light outputs.
Or maybe you’re ready to jump into modern LED grow lamps and take full control over the type of light fed to your cannabis plants during various stages of maturity. The choice is yours! And you’ll find support communities for whatever decision you make.
Know Your Budget, And Stick To It
It’s important, especially in the cannabis industry, to run a lean business. With Federal and Local laws in a constant state of flux, you just can’t count on tradition means of commercial funding. Know how much you can spend on installing new or replacing existing ballasts.
While you are considering upgrading your commercial grow lights to HPS or LED lamps, it may be the perfect time to update your ballasts as well. This is because you can usually save a lot of money by purchasing a ballast-lamp-fixture kit rather than piece the upgrades individually.
If you are looking to take advantage of the benefits electronic ballasts have to offer, it’s a good idea to purchase kits that include your desired lamp, along with an appropriate ballast and reflector (like this one). Electronic ballasts can provide a more stable power supply for your lamps, as well as allowing them to shine their brightest.
If you’re ready to take the plunge into LED grow lights, then you’ll have several additional options available. How you choose to proceed will determine whether you keep your current ballasts and install “plug and play” LED lights with integrated drivers, or bypass your ballasts all together.
Personal Preference
“Magnetic ballasts are durable, last a long time, can withstand cold or cooler temperatures, and have fewer parts to fail!” If you’re a strong believer in the old technology, and even more so with the advancements in MB technology – then we fully support swapping MBs with MBs.
However, if you do not currently have a strong personal preference, you may wish to consider building your grow facility with LED lights and drivers, or take advantage of all the benefits electronic ballasts (EB) have to offer.
If money is no option, and you don’t already have an established cultivation strategy or ballast preference, then we recommend considering EB making the jump into LED grow lamp technology.
Electromagnetic Interference vs. Light Flicker and Noise
Some would argue that you get the most out of your grow lamp using the sophisticated electronic ballasts. And they’re not wrong. In addition to eliminating the “hum” heard from MB, they operate on such a high frequency that your lamps won’t visibly flicker as well.
Although EB eliminate humming noises and light-flicker, they have been known to emit strong levels of radio and electronic interference. Having your cell phone disrupted while working in your cultivation facility may not be a big deal.
However, if your EB are not properly shielded, you could find local authorities on your doorstep, wanting to see credentials that your cannabis or hemp greenhouse is properly licensed and legal. Driving by a farm or greenhouse that also disrupts your radio is a dead-giveaway that a large grow-room is nearby.
Naturally, we assume all our customers are operating within the law and growing cannabis responsibly. We just wanted to point out that EMI is a thing, and could cause you a slight disruption to your day should you need to sure-up your business during a surprise visit.

Need more help?
We hope you found this article helpful and informative. Lighting ballast technology continues to improve, as do the grow lamps themselves.
If you have a ballast that needs replaced, or are looking to build or upgrade an indoor grow room, feel free to reach out to our team. We’re happy to help and provide additional resources and answer any other questions you may have.