Connect with us

microwave oven power cooking levels?

Discussion in 'Electronic Repair' started by wave, Dec 8, 2004.

  1. wave

    wave Guest

    Have spent over 2 hours trying to find out if most or all microwaves do true
    variable power output as opposed to the traditional cycling on & off to
    attain different power levels, panasonic call this inverter technology, they
    make it sound like they are the only ones that do it, have not been able to
    determine if this is so yet, I searched webpages as well as the newsgroup
    archives but frustratingly I could not find the answer to what I would have
    thought would be a common question.
     
  2. James Sweet

    James Sweet Guest

    The vast majority of microwaves cycle the magnetron, only the inverter type
    can do true variable power. I don't know if only Panasonic does this, but
    one way to tell would be the weight, a conventional transformer power supply
    will be considerably heavier, and the ovens will be cheaper as well.
     
  3. Frank

    Frank Guest



    Ring a few shops, but far as I know Only Panasonic has it..
     
  4. wave

    wave Guest

    I would never trust what the shops told me, have far to many times received
    completely wrong advise, in fact I would be hard pressed to think of 1
    occasion where they did not give completely wrong facts.
     
  5. wave

    wave Guest

    Thanks, I have very little experience with microwaves but I have used a
    panasonic with inverter technology and a much older microwave and the
    panasonic was definitely better at cooking evenly etc..., don't know if this
    was to do with the inverter technology or some other improvement in modern
    microwaves but it makes some sense to me that the inverter technology would
    give better cooking, a pity it is not standard among all microwaves then.
     
  6. wave

    wave Guest

    I know only panasonic call it inverter technology but I thought others could
    be using the same technology without calling it inverter which is only a
    name that panasonic have come up with to give this technology a brand and of
    course this will be copyrighted so nobody else can use the term inverter in
    their microwave ovens, i.e a marketing strategy.
     
  7. James Sweet

    James Sweet Guest

    I don't think "inverter" can be copyrighted, it's a name that's been in use
    for many years to describe certain types of switchmode power supplies. You
    can bet that if any other oven manufacture was using similar technology,
    they'd point it out in some obvious way even if they couldn't call it
    Inverter.
     
  8. James Sweet

    James Sweet Guest

    It's expensive to build, that's why it's not standard so far, but give it
    time. Cooking even-ness is more a matter of cavity and waveguide design than
    the power supply, I don't know about you but I don't remember the last time
    I used anything less than full power to cook in a microwave, the lower power
    I've only used for defrosting. I still think the inverter power supply is
    cool, I just don't think it'll have all that noticeable of an effect on
    cooking.
     
  9. NSM

    NSM Guest

    | Have spent over 2 hours trying to find out if most or all microwaves do
    true
    | variable power output as opposed to the traditional cycling on & off to
    | attain different power levels, panasonic call this inverter technology,
    they
    | make it sound like they are the only ones that do it, have not been able
    to
    | determine if this is so yet, I searched webpages as well as the newsgroup
    | archives but frustratingly I could not find the answer to what I would
    have
    | thought would be a common question.

    I have one of these and AFAIK only Panasonic is using it. 'Genius' is their
    trademark, inverter technology is not. It's a very powerful switchmode power
    supply that varies the input power to the microwave. BTW, don't buy the
    convection version - they are a swine to keep clean.

    All other makes I know of cycle power to control cooking which does not work
    as well for some items (oatmeal for one).

    N
     
  10. Inverter is a common electronic term. It sounds impressive to the masses.
    But, it's a much more complex technology than the traditional 3 component
    high voltage power supply used in the vast majority of microwave ovens.

    I don't really see how it's going to be much better at cooking except for
    very short cooking times where the normal cycling doesn't have enough
    resolution, time wise.

    More info in the Microwave Over Repair Guide at the site below.

    --- sam | Sci.Electronics.Repair FAQ Mirror: http://repairfaq.ece.drexel.edu/
    Repair | Main Table of Contents: http://repairfaq.ece.drexel.edu/REPAIR/
    +Lasers | Sam's Laser FAQ: http://repairfaq.ece.drexel.edu/sam/lasersam.htm
    | Mirror Sites: http://repairfaq.ece.drexel.edu/REPAIR/F_mirror.html

    Note: These links are hopefully temporary until we can sort out the excessive
    traffic on Repairfaq.org.

    Important: Anything sent to the email address in the message header is ignored.
    To contact me, please use the Feedback Form in the FAQs.
     
  11. The sample I have drives both the magnetron high voltage and filament
    from the same transformer. I would think this is hard on the magnetron
    at moderate power where the filament isn't as hot as it should be but
    perhaps it's not a big issue.

    --- sam | Sci.Electronics.Repair FAQ Mirror: http://repairfaq.ece.drexel.edu/
    Repair | Main Table of Contents: http://repairfaq.ece.drexel.edu/REPAIR/
    +Lasers | Sam's Laser FAQ: http://repairfaq.ece.drexel.edu/sam/lasersam.htm
    | Mirror Sites: http://repairfaq.ece.drexel.edu/REPAIR/F_mirror.html

    Note: These links are hopefully temporary until we can sort out the excessive
    traffic on Repairfaq.org.

    Important: Anything sent to the email address in the message header is ignored.
    To contact me, please use the Feedback Form in the FAQs.
     
  12. I was intrigued by this and other posts on the subject. Here is what I
    conclude off the top of my head. I may be wrong in part. It sure is
    difficult to glean specific information from the Panasonic web pages.

    The inverter substitutes high frequency electronic switching and a SMALL
    transformer for a much heavier magnetic transformer to provide the high
    voltage necessary to operate a magnetron. The switching also allows varying
    the voltage applied to the magnetron. In turn, that varies the magnetron's
    output level. A conventional transformer's output voltage is not easily
    changed. The down side is that efficency is reduced somewhat, especially at
    low cooking level. That is, a larger fraction of the electrical power you
    pay for ends up heating things other than food you are trying to heat.

    Running transformers at high frequencies, what the inverter does, reduces
    the size and weight required to handle large powers. The cost of electronic
    devices such as transistors has dropped as manufacturing techniques
    improved. Magnetic components such as transformers have not dropped much, if
    any, in price. To a large extent, cost and size for these components vary
    together.

    Bill
     
  13. Jim Yanik

    Jim Yanik Guest

    Price-wise that's strange,as it's cheaper to make a switcher than it is to
    make a big,iron-core transformer. That's why most electronics went to
    switchers;it's cheaper than 50/60hz iron transformers,especailly at higher
    power levels.
     
  14. NSM

    NSM Guest

    |
    | > I know only panasonic call it inverter technology but I thought others
    could
    | > be using the same technology without calling it inverter which is only a
    | > name that panasonic have come up with to give this technology a brand
    and of
    | > course this will be copyrighted so nobody else can use the term inverter
    in
    | > their microwave ovens, i.e a marketing strategy.
    |
    | Inverter is a common electronic term. It sounds impressive to the masses.
    | But, it's a much more complex technology than the traditional 3 component
    | high voltage power supply used in the vast majority of microwave ovens.
    |
    | I don't really see how it's going to be much better at cooking except for
    | very short cooking times where the normal cycling doesn't have enough
    | resolution, time wise.

    It definitely is better. Try defrosting fish without cooking the edges and
    you'll see. It's also very hard to cook oatmeal or similar food without it
    exploding.

    N
     
  15. NSM

    NSM Guest

    | in article , wave at [email protected] wrote on 12/8/04
    2:38

    | I was intrigued by this and other posts on the subject. Here is what I
    | conclude off the top of my head. I may be wrong in part. It sure is
    | difficult to glean specific information from the Panasonic web pages.
    ....
    | Running transformers at high frequencies, what the inverter does, reduces
    | the size and weight required to handle large powers. The cost of
    electronic
    | devices such as transistors has dropped as manufacturing techniques
    | improved. Magnetic components such as transformers have not dropped much,
    if
    | any, in price. To a large extent, cost and size for these components vary
    | together.

    Mine has a big ass inverter transformer wound with what looks like 1/4"
    thick Litz wire (multiple strands to prevent surface effects).

    N
     
  16. Jim Yanik

    Jim Yanik Guest

    My 30 year old Sharp cooks my daily oatmeal just fine.
     
  17. Jim Yanik

    Jim Yanik Guest


    lower filament voltage means longer tube life.
    It would not be hard to include a regulated filament supply,though.
     
  18. NSM

    NSM Guest

    | > All other makes I know of cycle power to control cooking which does
    | > not work as well for some items (oatmeal for one).

    | My 30 year old Sharp cooks my daily oatmeal just fine.

    So does my old 600W Toshiba, but my 1200W Sharp tends to explode it.

    N
     
  19. NSM

    NSM Guest

    |
    | > The vast majority of microwaves cycle the magnetron, only the inverter
    | > type can do true variable power. I don't know if only Panasonic does
    | > this, but one way to tell would be the weight, a conventional
    | > transformer power supply will be considerably heavier, and the ovens
    | > will be cheaper as well.
    |
    | Price-wise that's strange,as it's cheaper to make a switcher than it is to
    | make a big,iron-core transformer. That's why most electronics went to
    | switchers;it's cheaper than 50/60hz iron transformers,especailly at higher
    | power levels.

    Judging by the weight I think many new ovens use switchers, but don't
    modulate them.

    N
     
  20. 1/4" litz seems crazy to me! A layer of litz 1/4" in diameter or thickness
    made from finer litz would make more sense. How many turns are there of this
    litz?

    Bill
     
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-