Tech Made Simple

Hot Topics: How to Fix Bluetooth Pairing Problems | Complete Guide to Facebook Privacy | How to Block Spam Calls | Snapchat Symbol Meaning

author photo

Microwave Ovens with Inverter Technology Really Cook

by Josh Kirschner on October 28, 2009
in Health and Home, Kitchen, Guides & Reviews, Time Savers
Rating: 5 Stars five stars

Techlicious editors independently review products. To help support our mission, we may earn affiliate commissions from links contained on this page.

kitchen with microwave ovenIf you’re like most of us, your microwave oven serves two main duties: boiling water and reheating leftovers. But wouldn’t it be great if rather than just taking up a chunk of space in your kitchen, you could actually rely on your microwave for cooking meals?

Cooking food successfully in a microwave is challenging because the magnetron, the element that cooks the food in most microwaves, can only deliver full power. Even when set to “50% power”, the microwave oven is actually going through cycles of delivering 100% power, followed by a period of no power.

Imagine if your regular oven worked this way! Instead of cooking a roast at 350 degrees, you’d cook it at 700 degrees for ten minutes, then take it out for ten minutes, and repeat over and over again until the meat is cooked. Good luck with that!

The Microwave Inverter Solution

inverter vs. conventional microwavesPanasonic and GE have microwave ovens on the market with something they call “inverter” technology, which aims to solve this problem. The inverter modulates the level of energy being transmitted by the oven to achieve a consistent level. So when you set 50% power, for example, you actually get a steady stream of 50% power for the entire cooking time. The result is more evenly cooked food, defrosting without cooked edges, and even the ability to keep foods warm until mealtime.

Update 6/13/13: Whirlpool AccuWave and KitchenAid Optimawave ovens use the same technology.

Panasonic NN-SD688SWe spent a few weeks with Panasonic’s NN-SD688S, a 1.2 cubic foot counter top model with 1300 watts, to see how it worked out. Using recipes from Panasonic’s site, including some produced by the prestigious Culinary Institute of America specifically for inverter microwaves, we made hollandaise sauce, fruit crisp, corn chowder, barbecued pulled pork and some other fun dishes.

What we found was that the microwave inverter performed surprisingly well for dishes that required slow cooking in moist environments, such as the hollandaise sauce (which can be tricky to do on the stove top) and pulled pork. Corn chowder worked fine as well, though it would have been just as easy on the stovetop and we didn’t like moving large bowls of boiling liquid in and out of the oven. Perhaps not surprisingly, the fruit crisp was a flop, with a soggy, raw-tasting topping and overcooked fruit underneath.


Based on our experiences, we could easily see using an inverter microwave in addition to our standard cooktop and range, especially during busy holiday times when we are trying to cook many dishes at once, while also keeping everything warm until serving time. It is a fast and clean way to steam vegetables, melt chocolate, braise meats or do any one of a number of occasional kitchen tasks that involve steady cooking and do not require browning.

So if you are purchasing a microwave, we recommend that you give inverter models strong consideration. All Panasonic models also recently received the Good Housekeeping Seal, which provides a two-year limited warranty against defects.


Where to Buy

Panasonic Inverter microwave ovens: Buy Now at

Whirlpool AccuWave microwave ovens: Buy Now on Best Buy

KitchenAid Optimawave microwave ovens: Buy Now on Best Buy


UPDATE 6/24/17: With Whirlpool and KitchenAid no longer making inverter models, Panasonic is the remaining brand of choice for this technology. The Panasonic NN-SD945S was our recent winner in our Best Microwave Oven review. Read the article to find out why and learn about our opinion on whether Panasonic's new "cyclonic wave" inverter oven technology is worth the extra cost.

How to Make Microwaves Even Better

(An open call to manufacturers)

Our experiment with microwave recipes, even those written specifically for Panasonic inverters, clearly revealed another long-standing design flaw with all microwave ovens. It turned our initial attempt at crumbled bacon for the corn chowder into charcoal, and curdled our first run of hollandaise. The culprit is the nonsensical decision to use a scale of “1” to “10” to set the power level, rather than setting a specific wattage.

This abstract power scale becomes a significant issue with microwave recipes because it requires the cookbook author to assume a certain wattage in developing the recipe (often 800 watts, sometimes not). However, microwave ovens vary significantly in wattage, from around 700 watts to about 1400 watts. So a 700-watt oven will take approximately twice as long on “High” as a 1400-watt one to provide the same amount of cooking. To compensate, the cook needs to convert those times for her own oven based on its wattage.

But this assumes the cook knows what the original wattage was when the recipe was written and the wattage of her own oven. And if you don't know your wattage, don't bother looking on the oven. Amazingly, many manufacturers don't even print the wattage on their ovens! Talk about trying to make things difficult for cooks! Algebra with unknown variables is not something that should be required in the kitchen...

The solution to this is simple, however, and just requires one manufacturer to make the common-sense leap forward to allow all of their ovens to be set based on wattage delivered. This is the same logic that allows us to set our regular gas and electric ovens to 325 degrees, not “60% of the way around the blank dial”. Microwave recipes could then be written as “cook at 800 watts for five minutes”, which would be easy for a cook to apply for any oven from any brand.

Discussion loading

I see, most of the

From pawan on August 02, 2019 :: 9:06 pm

I see, most of the microwaves by Panasonic are based on its inverter technology, which is good for the efficient cooking power.


Panasonic Model Number differences?

From Paul Dalton on January 06, 2020 :: 6:00 pm

Do you happen to know anything about differences in the Model Nos of Panasonic’s Microwave Ovens?  I cannot get a substantive response from Panasonic support. 

Our NN-SN651W (Inverter) died after several years of use.  We liked it, except for its size.  We found a larger model - NN-SN975S - at Sam’s Club, but the Panasonic website only lists an NN-SD975S model, nothing about the NN-SN975S. 

From photos, I can see that the NN-SD975S has a knob, but the NN-SN975S does not.  I can’t tell what that means or whether there are any other differences between these two.  I’ve sent emails and made phone calls, but I cannot get anyone at Panasonic who will tell me the differences between these two models. 

Do you know or have any suggestions? 



Controls and "cyclonic" feature

From Josh Kirschner on January 13, 2020 :: 3:10 pm

All of the Panasonic 2.2CF inverter microwaves have the same basic cooking technology as far as wattage (1250W) and the inverter. However, the NN-SD975S also adds Panasonic’s relatively new “cyclonic wave” technology, which aims to more evenly distribute the waves throughout the interior of the oven. We haven’t tested cyclonic vs non-cyclonic to determine what impact, if any, that makes.

As you noted, the control methods are different between the two models, but they appear to offer largely the same cooking features as far as presets, etc. So it really comes down to a matter of preference.


Interference with WIFI signals

From David Stoker on June 18, 2020 :: 1:20 pm

WE have a Panasonic microwave oven with Inverter technology, but have noticed that it interferes with WIFI in our home. It stops the signal to our TV and also to our cell phones. Would this be a malfunction in our oven?


Panasonic NN-CD87KSBPQ 1000W 34Litre

From Linden Wong on September 06, 2020 :: 6:17 pm

My husband bought this microwave oven in July this year just as our 10 year old regular Panasonic 750 W was packing up. Due to space constraint we opted to purchase a tabletop microwave oven over a cooker - oven. I absolutely love using this little wonder. Pre heating is a breeze and cook time is drastically reduced. I never fail to be amazed by its energy efficiency. It’s particularly impressive when it comes to cooking using the Combi feature.


Seems too much like an

From Rodney Alan Armarego on September 08, 2020 :: 12:30 am

Seems too much like an advertisement.

To be believable it needs to have the bad points as well.. there are always some


Not an advertisement

From Josh Kirschner on September 08, 2020 :: 10:03 am

This is not an advertisement, sometimes we just really like a particular technology implementation. If you read our article on the Best Microwave Oven I do discuss some of the negatives of the Panasonic ovens themselves, notably with longevity issues on the inverter. Though, microwave reliability is a problem across the board with all brands.


I too am a fan

From Rodney Alan Armarego on September 08, 2020 :: 8:44 pm

I too am a fan of nation Panasonic inverter technology..

But if a review contains no bad points.. I distrust it.



From owen on September 08, 2020 :: 10:19 am

Kindly assist me with a capable firm that can repair my Microwavwe Oven Panasonic Model No:NN-C2003S.


Owen,Based in Potchefstroom,NW Province
065 994 1762


What, if anything, is the

From David Starr on October 08, 2020 :: 6:21 pm

What, if anything, is the difference between “inverter” & “cyclonic wave inverter”. If the latter is better, is it in all Panasonic inverter microwaves and in no other brands with inverters e.g. L G.?


Cyclonic is a way of distributing the waves inside the oven

From Josh Kirschner on October 13, 2020 :: 9:25 am

The inverter is a component of the microwave that reduces the power from the magnetron, enabling you to cook food more slowly. Both the standard Panasonic microwaves and the “cyclonic” use the same inverter technology. The “Cyclonic” feature is a means of distributing the waves more evenly inside the microwave, which Panasonic claims will result in more even cooking. So, Inverter reduces wave power, cyclonic distributes waves more evenly. I haven’t tested the cyclonic feature against a non-cyclonic oven, though I would expect benefits to be limited. Other brands may have a similar function to cyclonic, but call it something different than what Panasonic does.


A Cr*p microwave from a cr*p company

From richard baumer on October 10, 2020 :: 3:16 pm

Unlike Mr. Kirchner, I use the microwave for EVERYTHING. I do have a stove with an oven which I use every couple of months.  My Panasonic inverter MW is a nightmare to use.  You have to reduce the power level for everything except heating coffee and you have to reduce it more for ‘dense foods’.  No one can explain what a ‘dense food’ is.  I offered to send Panasonic a list of the microwave meals I normally eat and have them tell me whether they were dense or not and they told me they wouldn’t be able to tel!!!  The MW has been getting weaker lately and when I called Panasonic they suggested I drive it over to a repair facility in a nearby state!!!!  Unbelievable.  I intend to sell this one on Craig’s list for a dollar with appropriate warnings.


Some advice

From Josh Kirschner on October 13, 2020 :: 9:33 am

With “dense” foods, the microwaves will not penetrate as far, so you want to use lower power to allow time for the heat to carry into the interior of your food without overcooking the outside. Dense foods will typically be ones that contain a lot of water or are saucy (think dense lasagna vs less-dense broccoli). If you find this too complicated, you may want to just use the Panasonic’s autocook modes.

Any microwave from any brand will have these same issues. The difference is that Panasonic allows you to control the power of the microwaves in a much more precise manner. And if you are coming from an old, low-wattage microwave (maybe around 800 Watts) to a new 1250 Watt Panasonic, you will definitely see faster cooking.


G.E. was better.

From richard baumer on October 16, 2020 :: 2:29 pm

You work for Panasonic, don’t you.  The G.E. microwave I had before this one was better!  It matched the instructions provided on the meals I prepared. A big plus! As I have said before, This panasonic cooks unevenly and is getting weaker.  Fortunately, it is likely to break altogether soon and I will be able to defend buying another - not inverter - G.E. microwave.


Just got my Inverter model today

From Nancy Dubin on October 25, 2020 :: 2:44 pm

Great info. Funny but was looking for a converter chart for numbers 1-10 to approximate oven temps. First use on a side dish prepackaged food—box recipe says 1000 watts for 5 min.  Found an online conversion chart says 1200watts for 4 min 10secs.  Result was a bit of overflow on the glass dish. Upgraded model so I hope it might be door latch- my last microwave lasted 2 1/2 months!! First it arced, next day it blew a microwave safe dish to smithereens !!  Returned with no no problems. All my older microwaves were Panasonic soon just went back to them!


Declare wattage on recipes

From Robert on March 03, 2021 :: 2:28 pm

The article is spot on in stating that power levels, by themselves, are almost worthless.  A huge help would be if microwave recipes state the power wattage being used.  That would give the consumer some idea of any correction that needs to be made.

  A typical direction of “Microwave on high for 3 minutes” is meaningless.  What is so hard for the product to include the text such as “at 800 watts?”  There is room to add the text to the packaging.


Multi-step capability

From Jack Taylor on September 05, 2021 :: 12:18 pm

After many years of use, my old Sharp model has died. That one allowed selecting a sequence of stages. For example full power for 90 seconds followed by 20% power for three minutes would bring oatmeal to a boil and the cook it for three minutes without overflowing the bowl. I can not find that same sort of “steps” sequence being specifically noted on any but commercial models. Is that chaining together of steps available on most of the current middle to upper level homeowner models, say $200 -$300 (US)?


The Panasonic models have stage cooking

From Josh Kirschner on September 08, 2021 :: 9:20 am

The higher-end Panasonic models, such as our pick for the best microwave oven, have “Stage” cooking that will do what you’re describing.


Do Panasonic inverter microwave ovens have capacitors?

From Rodney Armarego on September 07, 2021 :: 12:22 am

Hi I’m trying to recover a Panasonic inverter the genius oven model number NN-T783SF 1200watt

Can someone please indicate you wear the capacitors are on this particular model from what I can see there doesn’t seem to be any capacitor there at all and I know that they are not hard to spot.

Any help gratefully accepted.


1 question, some answers...

From Robert Wadman on November 11, 2021 :: 3:37 am

I have now been using Panasonic microwaves for almost 20 years.  Started when their (at that time) newly PATENTED Inverter technology caught my attention, as I was working with 10kW (and larger) semiconductors used as invertors in some advanced welding equipment.  I have from then until now wondered why they seem to be the only brand of touch pad controlled microwave that does not use the “touch power button, touch number for power” scheme of programming.  I say this because no one else in family / friends have a Panasonic and all are baffled how to set power on it. 
As to the inverter used to provide “variable output power from the magnetron” it in fact DOES NOT.  In a “normal” microwave the magnetron is pulsed on and off at various rates so that over a 1 MINUTE time the AVERAGE power is reduced.  This is because a magnetron is operated by a high DC voltage that causes pulses or “oscillations” of electrons at extreme high frequencies (gHz / “microwave”), determined by the exact voltage and mechanical construction of the magnets around the central vacuum tube.  It can only be on or off - similar to a fluorescent light.  All the invertor does is take advantage of the extreme speed and WATTAGE that has become available in semiconductors.  Instead of a mechanical relay switching the power to the HV transformer on or off every few seconds,  the HV power supply is in continuous operation but applied through semiconductors in a “pulsed” fashion at something like a 100kHz rate.  So now by eliminating a variable percentage of the “pulses” you get the appearance of variable power because the averaging is being done across a 1 millisecond duration rather than a 1 minute duration.  So at 10% power a non-inverter microwave’s magnetron is probably on for 3 seconds, then off for 27 - not much use, eh?  The invertor microwave at 10% power is also off the same relative time, but does it by 3 milliseconds on then 27 milliseconds off or similar, repeating this high speed cycle at a hundred times a second or similar.  Though your food is still being blasted by full power, it is in extremely short pulses and the energy averaging works much better, allowing heat to propagate into the food rather than just heating the surface.
Second, I don’t understand the frequent comments through this thread about recommended oven wattage not being listed for foods.  “Microwave meals” and recipes / heating instructions on almost everything I have dealt with for 20 years have almost invariably finished with “times based on a #### Watt oven” - usually 1000 Watts these days, 15 years ago was more common to see 700 or 800.  I think too many people don’t read the full instruction, and also some use an * to try to get you to look for “fine print” at the bottom.
Third - you cannot actually “steam cook” anything in a microwave.  While it is true that microwave are most effective on water, it is also true that you can’t boil water in a microwave - watery mixtures, (like oatmeal) possibly, but water - no.  It is physics stopping you and you aren’t going to change the laws of physics.  When you put something in a stovetop steamer, it receives all of its heat from the water vapor at approx 210 degrees, and may absorb some of the water as well.  I you try that in the microwave you get far less steam, and A LOT of direct heating of the food from the microwaves themselves.  So if you are trying to make chinese steamed dumplings the centers may still be cold while the outside is hot and wet on top but nearly dry on the bottom facing the dish.
Because the watts per second can be reduced I have found I not only don’t have to set butter out to soften an hour before starting to make cookie dough, I can take it straight from the freezer, thaw and soften it without melting any of it.  And crispy bacon without burning it?  A couple minutes at 8,9, or 10 to “cook” it, them a few minutes at 3 to dry it out - makes it real crisp and you have to overshoot the low power time by several minutes before it becomes unusable for crumbled bacon.


Recipe Wattage

From Bob on November 14, 2021 :: 11:02 am

A few manufacturers do specify the wattage on which their cooking times are based.  Regrettably, a vast majority of manufacturers still do not specify the wattage—so a consumer has to guess.
The usual “weasel words” are always included, along the lines of “Oven cooking varies, so you may have to adjust your times.”
Giving the wattage used, at least, gives the consumer a fighting chance of getting it right the first time.  Text is cheap, put it on the package!


Read More Comments: 1 2 3

Home | About | Meet the Team | Contact Us
Media Kit | Newsletter Sponsorships
Accessibility Statement
Terms of Use | Privacy & Cookie Policy

Techlicious participates in affiliate programs, including the Amazon Services LLC Associates Program, which provide a small commission from some, but not all, of the "click-thru to buy" links contained in our articles. These click-thru links are determined after the article has been written, based on price and product availability — the commissions do not impact our choice of recommended product, nor the price you pay. When you use these links, you help support our ongoing editorial mission to provide you with the best product recommendations.

© Techlicious LLC.