Reduce power of a microwave oven?

M

mike

Guest
My 27 year old microwave oven was down below 400W output and taking a long
time to heat my coffee.
So, I went out and bought a 1100W one.
Big mistake.
It works fine on coffee, but WAY overcooks small stuff.
Yes, it has a power level setting, but the on-time is 15 seconds
and they modulate the off-time.
I tried to heat a frozen hamburger patty. It boils the liquid around
the outside for 15 seconds, but the inside is still frozen.
This really messes up the cheese stuck to it. If I leave it in
the frozen burger, it comes out awful.

What are my options for reducing power?
Yes, I can stick in a pot of water to absorb energy, but I'm
looking for a more elegant solution.
I assume there's nothing I can do on the primary side, cause of the
filament voltage requirements.
Assuming I can find a switch that can take the voltage and current,
can I switch the value of the big cap? Not much else in there to play with.

Alternatively, there's stuff they put in the bottom of microwave popcorn
that heats up from microwaves. What is that stuff? Maybe I can find a
pan with that in the bottom to average out the energy over time.
There's a "as seen on TV" serving plate that you heat in the microwave.
It's made of granite. What is it in the granite that gets heated?
IF I could find a square of floor tile in ceramic or granite, ceramic is
more easily available, I could stick one of them in the bottom of the oven.

Suggestions?
Thanks, mike
 
Can you return the oven? You can use the argument that it's not fit for its
intended purpose. Which it isn't.

I always assumed variable power was simple duty-cycle variation --
pulse-width-modulation -- over a fraction of a second. That the "on" time
would be fixed at 15 seconds (!!!), with the off time varied, is absurd. It
would produce exactly the effect you see.

There's also the possibility your sample is defective.

The stuff at the bottom of a microwave-popcorn bag is called a susceptor
sheet. I think it's a ferrite material, but I'm not sure.

http://en.wikipedia.org/wiki/Susceptor

Without any food to absorb heat from the susceptor, it would probably
overheat and burn fairly quickly.

You might try putting a brick on the oven, on the remote chance
fire-hardened clay absorbs microwaves. Bricks made with metallic colorants
might be the best place to start.
 
mike wrote:
My 27 year old microwave oven was down below 400W output and taking a long
time to heat my coffee.
So, I went out and bought a 1100W one.
Big mistake.
It works fine on coffee, but WAY overcooks small stuff.
Yes, it has a power level setting, but the on-time is 15 seconds
and they modulate the off-time.
I tried to heat a frozen hamburger patty. It boils the liquid around
the outside for 15 seconds, but the inside is still frozen.
This really messes up the cheese stuck to it. If I leave it in
the frozen burger, it comes out awful.

What are my options for reducing power?
Yes, I can stick in a pot of water to absorb energy, but I'm
looking for a more elegant solution.
I assume there's nothing I can do on the primary side, cause of the
filament voltage requirements.
Assuming I can find a switch that can take the voltage and current,
can I switch the value of the big cap? Not much else in there to play with.

Alternatively, there's stuff they put in the bottom of microwave popcorn
that heats up from microwaves. What is that stuff? Maybe I can find a
pan with that in the bottom to average out the energy over time.
There's a "as seen on TV" serving plate that you heat in the microwave.
It's made of granite. What is it in the granite that gets heated?
IF I could find a square of floor tile in ceramic or granite, ceramic is
more easily available, I could stick one of them in the bottom of the oven.

Suggestions?
Click to expand...

RTFM to see how to set the cook power.


--
You can't fix stupid. You can't even put a band-aid on it, because it's
Teflon coated.
 
Michael A. Terrell wrote:
mike wrote:
My 27 year old microwave oven was down below 400W output and taking a long
time to heat my coffee.
So, I went out and bought a 1100W one.
Big mistake.
It works fine on coffee, but WAY overcooks small stuff.
Yes, it has a power level setting, but the on-time is 15 seconds
and they modulate the off-time.
I tried to heat a frozen hamburger patty. It boils the liquid around
the outside for 15 seconds, but the inside is still frozen.
This really messes up the cheese stuck to it. If I leave it in
the frozen burger, it comes out awful.

What are my options for reducing power?
Yes, I can stick in a pot of water to absorb energy, but I'm
looking for a more elegant solution.
I assume there's nothing I can do on the primary side, cause of the
filament voltage requirements.
Assuming I can find a switch that can take the voltage and current,
can I switch the value of the big cap? Not much else in there to play with.

Alternatively, there's stuff they put in the bottom of microwave popcorn
that heats up from microwaves. What is that stuff? Maybe I can find a
pan with that in the bottom to average out the energy over time.
There's a "as seen on TV" serving plate that you heat in the microwave.
It's made of granite. What is it in the granite that gets heated?
IF I could find a square of floor tile in ceramic or granite, ceramic is
more easily available, I could stick one of them in the bottom of the oven.

Suggestions?


RTFM to see how to set the cook power.
Click to expand...
Amazing!!!
RTFM reply when I stated EXACTLY how the power setting works.
How about RTFOP?
 
William Sommerwerck wrote:
Can you return the oven? You can use the argument that it's not fit for its
intended purpose. Which it isn't.
Click to expand...
Nope, my inability to forecast the consequences is not the fault of the
seller.
I always assumed variable power was simple duty-cycle variation --
pulse-width-modulation -- over a fraction of a second. That the "on" time
would be fixed at 15 seconds (!!!), with the off time varied, is absurd. It
would produce exactly the effect you see.
Click to expand...
Yep, that's the way most of 'em work. The problem is the filament in
the magnetron. Much shorter and you don't get any power out cause
the filament ain't hot yet. With enough mass inside the oven, it
averages out pretty well. For a single frozen hamburger at 1100W, not
so much.

Yes, you can buy a microwave with fine-grained setting of continuous
power at most any retailer...for 3X the price.
They have to keep the filament hot while reducing the power. Much more
complicated and not a commodity item >> much higher price.
There's also the possibility your sample is defective.

The stuff at the bottom of a microwave-popcorn bag is called a susceptor
sheet. I think it's a ferrite material, but I'm not sure.

http://en.wikipedia.org/wiki/Susceptor

Without any food to absorb heat from the susceptor, it would probably
overheat and burn fairly quickly.
Click to expand...
They used to make browning plates with some kind of susceptor in the bottom.
Seems the only place you get 'em today is from TV infomercials at
high prices or on ebay at antique prices.

I do have a microwavable trivet that claims to be made from granite.
Gets hot alright, but it's encased in plastic and not well coupled
to whatever you put on it. A couple of experiments suggest that
while it does divert significant power, it will probably overheat
trying to do what I want.

A cup of water solves the problem, but it's not very elegant.
You might try putting a brick on the oven, on the remote chance
fire-hardened clay absorbs microwaves. Bricks made with metallic colorants
might be the best place to start.
Click to expand...
There's considerable range of microwave absorbency. I was hoping to find
some kind of commonly available ceramic, like floor tile, that
would work. That's why I asked for input.
Wonder what Home Depot would think if I packed tile samples
into the employee lounge and stuffed 'em into the microwave?
 
On 1/18/2011 5:55 PM mike spake thus:

Michael A. Terrell wrote:

mike wrote:

My 27 year old microwave oven was down below 400W output and
taking a long time to heat my coffee. So, I went out and bought a
1100W one. Big mistake. It works fine on coffee, but WAY
overcooks small stuff. Yes, it has a power level setting, but the
on-time is 15 seconds and they modulate the off-time. I tried to
heat a frozen hamburger patty. It boils the liquid around the
outside for 15 seconds, but the inside is still frozen. This
really messes up the cheese stuck to it. If I leave it in the
frozen burger, it comes out awful.

What are my options for reducing power?
Click to expand...
[snip]

Suggestions?

RTFM to see how to set the cook power.

Amazing!!!
RTFM reply when I stated EXACTLY how the power setting works.
How about RTFOP?
Click to expand...
Mr. Terrell apparently shoots from the hip and never apologizes.


--
Comment on quaint Usenet customs, from Usenet:

To me, the *plonk...* reminds me of the old man at the public hearing
who stands to make his point, then removes his hearing aid as a sign
that he is not going to hear any rebuttals.
 
In article <ih5hng$bfu$1@news.eternal-september.org>,
mike <spamme9@gmail.com> wrote:

Yep, that's the way most of 'em work. The problem is the filament in
the magnetron. Much shorter and you don't get any power out cause
the filament ain't hot yet. With enough mass inside the oven, it
averages out pretty well. For a single frozen hamburger at 1100W, not
so much.

Yes, you can buy a microwave with fine-grained setting of continuous
power at most any retailer...for 3X the price.
They have to keep the filament hot while reducing the power. Much more
complicated and not a commodity item >> much higher price.
Click to expand...
Not that much higher these days, I think. The Toshiba "inverter"
microwave ovens have a variable power level of this general sort, and
they're commodity items to the extent of being buyable at Costco and
probably other big-box stores. They're somewhat more expensive than
ovens fixed-power magnetrons, but not all that much.

However... I had one, and it died within a couple of years in home
use. Our previous microwave had lasted for a couple of decades. I'm
not sure whether this was an odd failure in this unit, or was
characteristic of Toshiba inverter microwaves in general, or just an
result of the "race to the bottom, in price and in quality" which
seems to be affecting the whole consumer-electronics business these
days.

I bought a fixed-power-output commercial-service Amana as a
replacement, in the hopes that it'll last rather longer than the
Toshiba did.

--
Dave Platt <dplatt@radagast.org> AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!
 
In article <ih536g$rco$1@news.eternal-september.org>,
mike <spamme9@gmail.com> wrote:

Yes, it has a power level setting, but the on-time is 15 seconds
and they modulate the off-time.
I tried to heat a frozen hamburger patty. It boils the liquid around
the outside for 15 seconds, but the inside is still frozen.
Click to expand...
Mike-

Does the new microwave have a Defrost option? If so, does it also cook
for 15 seconds at full power?

I had a small microwave back in the 70s that had a low power setting.
My memory is a little hazy, but I think the low power setting switched a
capacitor in series with the high voltage transformer primary. It acted
as a ballast to reduce magnetron voltage.

Fred
 
Your easiest solution may be to look for a new model that has the cooking
power levels that suit your needs.
I haven't looked at MWOs lately, but the revolving turntable should probably
be a major consideration.

From many years ago, I found that trying to cook numerous types of foods in
a microwave provided awful results, and never bothered to try them in more
advanced models.
Bacon, eggs, burger were some examples.

The fairly large MWO I use now was given to me a number of years ago, and
suits my needs for the types of foods that I want to be microwaved.
The manual has so many different types of cycles, that I don't even bother
to try to remember them.
I stick with the basic operations, which limits what the MWO will be used
for, but that's not a problem for me.

Typical MWOs aren't a good substitute for an actual range/stove (and
appropriate cookware, talent, time etc).
Also, one generally needs to find the types/brands of processed foods that
provide the user with something desirable to their own tastes.

The top crust of a pot pie should be browned.. the Marie Callendar(?) frozen
pies have a metallic grid made into the top of the box, and the crust always
browns (may not work with low-powered MWOs, I don't know for sure). The
minimum power recommended is marked on the box.
The 1 lb size pies are a decent portion, and taste good.. allow ample time
for cooling.

I don't have them anymore, but at one time I had a set of microwave dishes
with covers that were very useful.
They were a tan bakelite/melmac-type material with metal flakes visible in
the material.. they were a fairly common brand name in the U.S. but I'm not
sure what it was.
Anyway, I could get varied results with lid on , off or turned 45 degrees
(square dishes), which are all common techniques with conventional cooking.
So, the types of accessories and different techniques will yield more
options, and very different results.

I've found certain techniques that produce results which are more to my
personal liking.. such as always wrap/cover a sandwich in paper towel to
heat (prevents the bread/bun from getting hard spots without becoming
soggy), cover cold pizza also with paper towel, or better yet, eat it cold.
There are various options.. placing flat foods between two paper plates, or
tall sandwiches between two paper bowls.
There are various commercial plastic products/accessories for MWO use, but
those require washing.. disposable paper (not plastic/styrofoam) plates and
bowls, and plastic utensils don't.

I never put uncovered liquids or other types of foods that are a combination
of food/liquid in the MWO, I always use a paper plate as a cover. I can't
stand seeing a dirty MWO, and it's far easier to prevent eruptions than to
clean them up.
But then, I generally always wipe the interior down with a paper towel
dampened with 60/40% water/alcohol mixture that has a few drops of liquid
soap added per pint, to wipe out the condensed moisture, every time I use
the MWO.

--
Cheers,
WB
..............


"mike" <spamme9@gmail.com> wrote in message
news:ih536g$rco$1@news.eternal-september.org...
My 27 year old microwave oven was down below 400W output and taking a long
time to heat my coffee.
So, I went out and bought a 1100W one.
Big mistake.
It works fine on coffee, but WAY overcooks small stuff.
Yes, it has a power level setting, but the on-time is 15 seconds
and they modulate the off-time.
I tried to heat a frozen hamburger patty. It boils the liquid around
the outside for 15 seconds, but the inside is still frozen.
This really messes up the cheese stuck to it. If I leave it in
the frozen burger, it comes out awful.

What are my options for reducing power?
Yes, I can stick in a pot of water to absorb energy, but I'm
looking for a more elegant solution.
I assume there's nothing I can do on the primary side, cause of the
filament voltage requirements.
Assuming I can find a switch that can take the voltage and current,
can I switch the value of the big cap? Not much else in there to play
with.

Alternatively, there's stuff they put in the bottom of microwave popcorn
that heats up from microwaves. What is that stuff? Maybe I can find a
pan with that in the bottom to average out the energy over time.
There's a "as seen on TV" serving plate that you heat in the microwave.
It's made of granite. What is it in the granite that gets heated?
IF I could find a square of floor tile in ceramic or granite, ceramic is
more easily available, I could stick one of them in the bottom of the
oven.

Suggestions?
Thanks, mike
Click to expand...
 
On Tue, 18 Jan 2011 20:35:49 -0500, "Michael A. Terrell"
<mike.terrell@earthlink.net> wrote:

mike wrote:

My 27 year old microwave oven was down below 400W output and taking a long
time to heat my coffee.
So, I went out and bought a 1100W one.
Big mistake.
It works fine on coffee, but WAY overcooks small stuff.
Yes, it has a power level setting, but the on-time is 15 seconds
and they modulate the off-time.
I tried to heat a frozen hamburger patty. It boils the liquid around
the outside for 15 seconds, but the inside is still frozen.
This really messes up the cheese stuck to it. If I leave it in
the frozen burger, it comes out awful.

What are my options for reducing power?
Yes, I can stick in a pot of water to absorb energy, but I'm
looking for a more elegant solution.
I assume there's nothing I can do on the primary side, cause of the
filament voltage requirements.
Assuming I can find a switch that can take the voltage and current,
can I switch the value of the big cap? Not much else in there to play with.

Alternatively, there's stuff they put in the bottom of microwave popcorn
that heats up from microwaves. What is that stuff? Maybe I can find a
pan with that in the bottom to average out the energy over time.
There's a "as seen on TV" serving plate that you heat in the microwave.
It's made of granite. What is it in the granite that gets heated?
IF I could find a square of floor tile in ceramic or granite, ceramic is
more easily available, I could stick one of them in the bottom of the oven.

Suggestions?


RTFM to see how to set the cook power.
Click to expand...
Or use the defrost cycle!
 
Can you return the oven? You can use the argument
that it's not fit for its intended purpose. Which it isn't.

Nope, my inability to forecast the consequences is not
the fault of the seller.
Click to expand...
If your description is correct, the oven is grossly misdesigned. You do not
implement variable power by turning the magenetron on for 15 seconds, then
letting it sit for a minute! I've /never/ seen a microwave oven that works
that way. My home GE works fine, as do all those I've seen where I've
worked.


I always assumed variable power was simple duty-cycle variation --
pulse-width-modulation -- over a fraction of a second. That the "on" time
would be fixed at 15 seconds (!!!), with the off time varied, is absurd.
It
would produce exactly the effect you see.

Yep, that's the way most of 'em work. The problem is the filament in
the magnetron. Much shorter and you don't get any power out cause
the filament ain't hot yet. With enough mass inside the oven, it
averages out pretty well. For a single frozen hamburger at 1100W, not
so much.
Click to expand...
I've never heard of varying a magnetron's power by adjusting its filament
voltage! I've always ASS+U+MEd there was some way of turning the tube on and
off by varying an electrode voltage. (Simply pulsing the anode voltage would
produce variable output.)
 
Bacon, eggs, burger were some examples.
Click to expand...
A microwave oven is ideal for bacon, because all it needs is a thorough
heating. Which is all a microwave oven does... It doesn't actully /cook/
anything.
 
On 1/19/2011 2:07 AM, Fred McKenzie wrote:

Yes, it has a power level setting, but the on-time is 15 seconds
and they modulate the off-time.
I tried to heat a frozen hamburger patty. It boils the liquid around
the outside for 15 seconds, but the inside is still frozen.


Does the new microwave have a Defrost option? If so, does it also cook
for 15 seconds at full power?
Click to expand...
Many new microwaves have and auto-defrost function (also usually an
auto-reheat) that measures the humidity while firing the magnetron for
short bursts. It runs this cyclically for a preset time based on your
food selection and weight while it calculates the actual time it should
take to defrost the food. Then it usually beeps once and finally runs
the defrost cycle that it calculated.

I find this works quite well once you get the hang of it.

--
-Scott
 
"William Sommerwerck" <grizzledgeezer@comcast.net> wrote in message
news:ih6qf4$6sk$1@news.eternal-september.org...
Can you return the oven? You can use the argument
that it's not fit for its intended purpose. Which it isn't.

Nope, my inability to forecast the consequences is not
the fault of the seller.

If your description is correct, the oven is grossly misdesigned. You do
not
implement variable power by turning the magenetron on for 15 seconds, then
letting it sit for a minute! I've /never/ seen a microwave oven that works
that way. My home GE works fine, as do all those I've seen where I've
worked.


I always assumed variable power was simple duty-cycle variation --
pulse-width-modulation -- over a fraction of a second. That the "on"
time
would be fixed at 15 seconds (!!!), with the off time varied, is absurd.
It
would produce exactly the effect you see.

Yep, that's the way most of 'em work. The problem is the filament in
the magnetron. Much shorter and you don't get any power out cause
the filament ain't hot yet. With enough mass inside the oven, it
averages out pretty well. For a single frozen hamburger at 1100W, not
so much.

I've never heard of varying a magnetron's power by adjusting its filament
voltage! I've always ASS+U+MEd there was some way of turning the tube on
and
off by varying an electrode voltage. (Simply pulsing the anode voltage
would
produce variable output.)
Click to expand...
All of the bog-standard microwave ovens that I've owned have worked exactly
like that - and it was fine when they were the 'standard' 600 or 650 watts
of a few years ago. However, now they are all 850 / 900 / 1000 watts, it's a
crap system of power control. The one I have at the moment, does exactly as
the poster's does when set to say 60% power. It's like 15 seconds on at full
chat, followed by 20 seconds at full off. 60% is what's needed for heating a
can of soup in a reasonable time to a reasonable temperature. And it's ok if
it's just a full liquid soup like say tomato. But as soon as you try to do
it with anything like perhaps vegetable, 15 seconds of microwaves at 850
watts, is enough to start exploding the peas or beans or barley grains, all
over the inside of the rotten thing. 600 watts didn't used to do this. If
you go to the next step down - ie 40% power - it takes forever to get the
bulk liquid of the soup up to an edible temperature.

Arfa
 
"William Sommerwerck" <grizzledgeezer@comcast.net> wrote in message
news:ih6qji$7hl$1@news.eternal-september.org...
Bacon, eggs, burger were some examples.

A microwave oven is ideal for bacon, because all it needs is a thorough
heating. Which is all a microwave oven does... It doesn't actully /cook/
anything.
Click to expand...
I seem to remember that we had this discussion once before some years back.
It depends on how you define the word "cook". Using the traditional
definition of 'preparing food by use of heat' I would contend that this is
exactly what a microwave oven does - or am I missing something ... ? If I
am, then what *is* cooking that a conventional oven does differently ?

Arfa
 
All of the bog-standard microwave ovens that I've owned have worked
exactly
like that - and it was fine when they were the 'standard' 600 or 650 watts
of a few years ago. However, now they are all 850 / 900 / 1000 watts, it's
a
crap system of power control. The one I have at the moment, does exactly
as
the poster's does when set to say 60% power. It's like 15 seconds on at
full
chat, followed by 20 seconds at full off. 60% is what's needed for heating
a
can of soup in a reasonable time to a reasonable temperature. And it's ok
if
it's just a full liquid soup like say tomato. But as soon as you try to do
it with anything like perhaps vegetable, 15 seconds of microwaves at 850
watts, is enough to start exploding the peas or beans or barley grains,
all
over the inside of the rotten thing. 600 watts didn't used to do this. If
you go to the next step down - ie 40% power - it takes forever to get the
bulk liquid of the soup up to an edible temperature.
Click to expand...
Fascinating. (In the correct Spock sense... "Fascinating I reserve for the
unexpected.")

I have a high-power GE microwave oven cum exhaust hood. Many foods -- such
as soup or oatmeal -- must be heated at half power (give or take), or you
get localized boiling, sometimes very quickly. I've never seen this happen
with reduced power. The oven always acts as if the magnetron is being
rapidly pulsed.

May I publicly apologize for believing that manufacturers ever use the least
bit of common sense when designing products?
 
"Arfa Daily" <arfa.daily@ntlworld.com> wrote in message
news:7qEZo.371$S16.147@newsfe20.ams2...
"William Sommerwerck" <grizzledgeezer@comcast.net> wrote in message
news:ih6qji$7hl$1@news.eternal-september.org...

Bacon, eggs, burger were some examples.

A microwave oven is ideal for bacon, because all it needs is a thorough
heating. Which is all a microwave oven does... It doesn't actully /cook/
anything.

I seem to remember that we had this discussion once before some
years back. It depends on how you define the word "cook". Using the
traditional definition of 'preparing food by use of heat' I would contend
that this is exactly what a microwave oven does - or am I missing
something ... ? If I am, then what *is* cooking that a conventional
oven does differently ?
Click to expand...
Your perfectly logical definition seems sufficiently generic to include
microwave ovens. In practice, "cooking" refers to either immersing
the-thing-to-be-prepared in a cavity full of hot air...

"Yeah, Sommerwerck -- yer mouth."

....(baking, roasting) or applying heat directly to it (frying) or from a
nearby source (broiling, grilling). Microwave "cooking" does none of
these -- it simply heats the-thing-to-be-prepared from the inside.

Oddly, the Wikipedia article claims that microwave cooking heats food more
evenly than any other method, when, in fact, it heats from the outside in,
as does every other cooking method, and can be extremely uneven, if part of
the dish is sitting in a standing-wave node.
 
Here, for example, is a patent for pulsed control of microwave-oven power.
It was filed for in 1975.

http://ip.com/patent/US4041267
 
On Wed, 19 Jan 2011 05:57:24 -0800, "William Sommerwerck"
<grizzledgeezer@comcast.net> wrote:

Bacon, eggs, burger were some examples.

A microwave oven is ideal for bacon, because all it needs is a thorough
heating. Which is all a microwave oven does... It doesn't actully /cook/
anything.
Click to expand...
let's face it, most cooking is just heating.
 
On Wed, 19 Jan 2011 05:55:03 -0800, "William Sommerwerck"
<grizzledgeezer@comcast.net> wrote:

Can you return the oven? You can use the argument
that it's not fit for its intended purpose. Which it isn't.

Nope, my inability to forecast the consequences is not
the fault of the seller.

If your description is correct, the oven is grossly misdesigned. You do not
implement variable power by turning the magenetron on for 15 seconds, then
letting it sit for a minute! I've /never/ seen a microwave oven that works
that way. My home GE works fine, as do all those I've seen where I've
worked.
Click to expand...
Huh? Virtually all the ones I've seen do just that: run a 10 to 15
second on/off time cycle. The magnetron is turned on with a relay, so
rapid cycling just begs to blow that relay.
 
You must log in or register to reply here.

Welcome to EDABoard.com

Sponsor

Back
Top