What’s the difference between magnetic and electronic power drivers? First, for the purpose of this article I may incorrectly (go here to see why) use the terms power supply, power driver and transformer interchangeably.
Whether a power supply is considered magnetic or electronic depends upon the internal ballast. The primary role of the ballast is to help regulate the flow of current.
Comparison of characteristics
| Magnetic driver | Electronic driver |
|---|---|
| Large transformer-like core power factoring capacitor and an Igniter | Converts AC to DC at a very high frequency using solid state components |
| May have visible flicker @ rate of 120/sec | No flickering |
| Narrow voltage/frequency input range | Wide voltage/frequency input range |
| Larger + heavier | Smaller + lighter |
| Simple design | Complicated design |
| Very reliable | Slightly less reliable due to complexity |
Now with that said, let’s take a step back and smooth any ruffled feathers. First, these are generalizations. Technology both with magnetic and electronic power supplies has come a long way. Let’s take, for example, two 12 volt-60 watt power drivers that we sell here.
Comparison of Specifications
| Property | Magnitude M60L12DC-AR (Magnetic) | Magnitude E60L12DC-KO (Electronic) |
|---|---|---|
| Price | $79.95 | $72.95 |
| Max Load | 60 Watts (12 Volts DC) | 60 Watts (12 Volts DC) |
| Input | 120 Volts AC | 120 Volts AC |
| Input Current (Full Load) | 760 mA @ 120 VAC | 610 mA @ 120 VAC |
| Output Current (Full Load) | 5 Amps @ 12 VDC | 5 Amps @ 12 VDC |
| Average Efficiency | 80% | >90% |
| Dimmable? | Yes | Yes |
| Warranty | 5 Years | 5 Years |
| Dimensions | 6.55" x 2.25" x 2.55" | 6.77" x 2.67" x 1.26" |
| Weight | 50 oz | 17 oz |
Analysis
By volume, the electronic driver is 61% the size of the magnetic one. By weight, it’s around 3x lighter (294% to be precise). For many, dare I say most installations, these numbers don’t matter. The electronic power supply is about 9% cheaper than the magnetic transformer.
Sounds great right? Well there are certainly some significant trade-offs. Magnetic power drivers are known to last ages, and they will often give signs of looming death before it comes. In the event of a failure outside their warranty period, they are often repairable (certainly more easily then the complex circuitry in an electronic driver).
Electronic power supplies, due to the complexity, can fail from one moment to the next. Once they’ve failed, diagnosing and fixing them can be difficult. This fact alone is why often professionals, when given the choice, will opt for magnetic units.
Flickering with Magnetic Transformers
Due to the nature of their design, magnetic transformers will flicker at a rate of about 120 iterations per second. To the human eye and most modern recording equipment this is nearly imperceptible. But…
If you will be using these lights in the presence of recording equipment which runs at a low frame rate (say 60 or below) you may end up with noticeable flickers in the video. It depends if, by chance, the flickering of the lights sync up to the recording’s frame rate.
RFI (Radio Frequency Interference) Output with Magnetic vs Electronic Power Supplies
If you are worried about interference with nearby electrical equipment (including a television or radio) then this may be a compelling reason for you to purchase a magnetic power driver.
Magnetic power drivers do not produce the RFI disturbances that electronic drivers are known for. This is particularly important to the HAM, CB, SSB and VHF enthusiasts out there (among any number of other RFI sensitive hobbies I’m not familiar with)!
Conclusion
What’s right for you? Unfortunately as with so many things in life, we can’t make this decision for you. Magnitude came onto the scene offering incredibly small, dimmable magnetic power drivers, and they’re very popular due to their reliability and performance. They should not be discounted because of a few drawbacks (such as size, weight and generally imperceptible flickering) that, frankly, do not have a significant effect on utility.
With that said, electronic drivers are sometimes chosen for their economy (both physical and monetary). Their ability to accept a wider range of input voltages also makes them more suitable to less stable conditions.
If you have any questions, feel free to leave us a comment below or contact us directly. And of course, we hope to earn your business when it comes time to make a purchase. Please let us know if we don’t offer what you need!
Thank you! Please keep up the posts. These seem honest and devoid of bias.
Thank you for this informative post. It answered my questions.
I am not in the habit of correcting others’ grammar, but the use of THEN instead of THAN stops me dead in my tracks every time.
“…(certainly more easily THEN the complex circuitry in an electronic driver).”
More…THAN.
If…THEN.
Thank you.
You didn’t mention any differences between noise generation of the two types… either at full light or minimum dimming percentage. My experience is only with fluorescent fixtures. Magnetic ballasts always make a perceptible noise.