You may have heard recommendations telling you that once you purchase a generator you’ll need to pick up a good power line conditioner. That the generator puts out “dirty” power, and that a power line conditioner will solve this problem.
So you may be asking yourself if this is true. Is using a power line conditioner with your generator something you should be investigating? With reliable power line conditioner costing a couple hundred dollars, this is a good question to ask rather than just making the purchase based on hearsay and uninformed recommendations.
Below is a table with our recommendations for the best power line conditioners. We are also dedicated to diving into the truth and need for these products when you purchase a portable generator for use at your home, job site, or anything in between.
Our Recommended Conditioner
Additional Recommended Generator Resources
What does a power line conditioner do?
What does a power line conditioner do to the power? Does it make “dirty” power safe for use? Well, it can get a bit technical if you’re not an electrician so hang with me and I’ll give you the basics without getting too mired down in terminology. Here in North America, we operate on an electrical grid that provides 120VAC at 60Hz.
In much of the rest of the world the power grid runs at 230VAC at 50Hz. The Alternating Current Voltage (VAC) being the “push” behind the power and the Hertz (Hz) being how many times it flips back and forth per second, hence the “alternating” term in AC. For the purposes of demonstration we’ll go with the North American standard.
The generator will attempt to put out the same electrical signal as your utility power, 120VAC at 60Hz, and will do a fairly good job of it which is why they are reliable for portable power. But the weakness is the engine; every time it’s not running at the perfect speed, there is a fluctuation in the output. As you draw more power, the engine has to ramp up speed. If there is a sudden burst of power from the engine, that voltage gets passed through to your output.
If you run out of fuel or there is a problem with the fuel source, the sputtering of the engine will produce a wildly fluctuating signal that will alternately spike and drop power. These are the moments when your more sensitive electronics can take damage. A power line conditioner simply smooths out these rough spots and minimizes power spike and loss. It makes the signal cleaner, but not quite clean enough.
Our Recommended Conditioner
Potential problems with portable generator power
The real problem with portable generator power is the harmonics it can produce on the electrical line. Think of a sinewave, that up and down waving line pattern you see in old science fiction movies. That’s your electrical signal. Now imagine the same sinewave flipped upside down on the original wave, that’s your draw. At the cleanest and most pure signal you can imagine, these two waves cancel one another out.
Your generator isn’t capable of creating pure clean signal. It is putting out a jagged shape with the closest approximation to that smooth clean sinewave signal as it can. The power line conditioner is doing its job of helping clean up that smooth line to make the waves cancel one another out, but it can’t do it enough to counter the phase shifting of these two waves. Phase shifting is the simple occurrence of hitting the same point on a regulated beat. The dirtier the signal is, the less likely it is to stay “on time”.
I told you I wasn’t going to get bogged down in technical terms. So I’ll translate this to musical terms. If one musician is counting to four (1, 2, 3, 4, 1, 2, 3, 4…) and another musician is counting to three (1, 2, 3, 1, 2, 3…) their respective “1” will meet up every 12th note and they will sync up. This creates a rhythmic pattern that neither of them are playing and yet is caused by the both of them.
This is the same as the electrical harmonic, it is a byproduct of two signals that are unmatched in speed causing the harmonic that can change the power being sent into your electronics.
Our Recommended Conditioner
A power line conditioner is not the ultimate solution for clean power
With the growing list of what constitutes “sensitive” electronics, it is all the more important to be aware of what kind of power your generator is putting out. Something as simple as a toaster might not be damaged by dirty power, but you never thought the coffee maker would either and now here we are with delicate chips and processors in our programmable coffee makers.
It’s no longer just computers, stereos, and televisions we have to worry about. Thermostats, ceiling fans, washers and dryers… they all have delicate electronics in them now. Even the refrigerator has a screen on it…
So while a power line conditioner will smooth out the fluctuations of a small generator’s natural surge and brownout conditions, the total harmonic distortion can still come through from the generator’s power feed and cause damage over time to the fragile components in some of your devices.
A power line generator is a good step in cleaning up the power, but if you want to truly protect your electronics, put a rectifier/inverter in line with your feed. The rectifier takes the alternating current with its fluctuating sinewaves and turns the power into VDC (direct current) where there is no flipping of the power phases.
The inverter takes this DC and turns it back into usable AC. If all this seems like an extravagant waste, there is a class of “inverter generators” that do this already and may be what you need instead of a line conditioner.
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