Microwave ovens

[bcps]

I've been looking for a 12 volt microwave oven. All that I find are in the
450 to 550 watt range and include an inverter. Odd that they say it runs
directly on 12 volts - so why do they include an inverter and even in some
cases, a coffee maker: I don't want an inverter and a coffee maker - I just
want a microwave that runs on 12 volts and preferrably a couple hundred
watts higher. Any suggestions?

 

[Jack Brown]

have you checked your nearest truck stop / trucker's store?

jb

 

[You]

I've been looking for a 12 volt microwave oven. All that I find are in the
450 to 550 watt range and include an inverter. Odd that they say it runs
directly on 12 volts - so why do they include an inverter and even in some
cases, a coffee maker: I don't want an inverter and a coffee maker - I just
want a microwave that runs on 12 volts and preferrably a couple hundred
watts higher. Any suggestions?

Have you ever considered the possibility that you lack the understanding
of the technology your complaining about???? Microwave Ovens use a
Magnitron Tube to produce the Cooking Power. This tube operates in the
Microwave Radio S Band. It requires about 2500 Volts of Direct Current
to operate. Just how do you figure to get that out of a 12 Volt Direct
Current Battery, without an Inverter????? Hmmmm, Inquiring Minds
certainly would like to know......

 

[bcps]

Have you ever considered the possibility that you lack the understanding
of the technology your complaining about???? Microwave Ovens use a
Magnitron Tube to produce the Cooking Power. This tube operates in the
Microwave Radio S Band. It requires about 2500 Volts of Direct Current
to operate. Just how do you figure to get that out of a 12 Volt Direct
Current Battery, without an Inverter????? Hmmmm, Inquiring Minds
certainly would like to know......

Um.... build it properly to operate on 12 volts? What does it matter? 12
volts, 2 volts, 5000 volts... all that counts is the power. I understand
the magnitron is a high voltage device and it requires a step up transformer
to function. But a microwave oven that is advertised as a 12 volt unit
should not require an external inverter - and it certainly doesn't need a 12
cup coffee maker in the loop.

The microwave ovens I'm talking about claim to run directly from 12 volts
and the comments made even talk about the fact that it is less efficient to
run a 120 vac microwave on an inverter. So why is it mandatory to buy an
inverter with the microwave?

By the way, I spent 6 years in the US Navy working on missile systems, the
last 30 years working with other forms of electronics, and I can make a 1.5
volt battery release enough power to drop a human. So please try not to
talk down to me like that any more - it is really annoying and rather
useless.

 

[bcps]

have you checked your nearest truck stop / trucker's store?

jb

I have to post at the bottom because there are so many uptight folks who
don't like top posters.

No, I haven't checked my nearest truck stop - but that is an excellent
suggestion! In fact, I got my present inverter from a gas station in
central florida - with the rebate, it was free!!! Unfortunately, I don't
travel as much as I use to. My favorite stop was Yeehaw Junction in
Florida. But I don't drive much anymore and it is not easy to get there on
a recumbent trike ;-)

But I will remember to check next time I'm on the road.

Thanks for reminding me.

 

[Mauried]

Um.... build it properly to operate on 12 volts? What does it matter? 12
volts, 2 volts, 5000 volts... all that counts is the power. I understand
the magnitron is a high voltage device and it requires a step up transformer
to function. But a microwave oven that is advertised as a 12 volt unit
should not require an external inverter - and it certainly doesn't need a 12
cup coffee maker in the loop.

The microwave ovens I'm talking about claim to run directly from 12 volts
and the comments made even talk about the fact that it is less efficient to
run a 120 vac microwave on an inverter. So why is it mandatory to buy an
inverter with the microwave?

By the way, I spent 6 years in the US Navy working on missile systems, the
last 30 years working with other forms of electronics, and I can make a 1.5
volt battery release enough power to drop a human. So please try not to
talk down to me like that any more - it is really annoying and rather
useless.

 

[bcps]

Microwave ovens are typically only 50-60% efficiency, so one rated at
800W cooking power usually pulls 1400W or more from its AC supply.

At 12V, that's over 116 amps! A medium- or high-power native 12V oven
would need to be hooked up with wire the size of welding cable (1/0
ore heavier), unless it were directly adjacent to your battery bank.

Look at the terminal lugs and recommended cable sizes for a large,
2000W inverter, like a Trace 2512. The microwave would be similar.

An outboard inverter can be placed close to your 12V source, with much
more reasonable cord carrying the stepped up 120VAC to your oven.
That's probably why they're kept as two separate units.

My batteries are less than 5 feet away from where I would intend on putting
the oven. My point was that they claim the oven operates at 12 volts with
no need for an inverter, but an inverter is included with it in all the
products I've seen. For example:

http://www.roadtrucker.com/feature-12-volt-microwave.htm

I already have a small 120vac microwave. If there is no such thing as a
true, stand alone, 12 volt microwave, then I should probably just upgrade my
inverter and forget about it...

 

[You]

So please try not to
talk down to me like that any more - it is really annoying and rather
useless.

but you DIDN"T answer the question..... Just how do expect to power a
Magnitron Tube that requires 2500Vdc, when your input is 12Vdc, without
an Inverter somewhere in the system????? Inquiring minds, still want to
know. For even a Swabbie, this isn't Rocket Science.....

 

[bcps]

but you DIDN"T answer the question..... Just how do expect to power a
Magnitron Tube that requires 2500Vdc, when your input is 12Vdc, without
an Inverter somewhere in the system????? Inquiring minds, still want to
know. For even a Swabbie, this isn't Rocket Science.....

Good grief... It would be designed and built into the system without the
need for an external inverter. And, by the way, it is spelled "magnetron" -
which I also misspelled, once... and the voltage tends to be a bit higher
than 2500 volts. I don't need a freaking inverter for a TV that runs on 12
volts, yet the CRT still demands 15000 + volts.

My main question was, if the oven claims to be a 12 volt microwave oven, why
does it have to come with an external inverter? Sounds like extra baggage
to me - just like the coffee maker. It also sounds like false advertising.
Kinda like selling an electric car that requires an external gas generator
to supply the electricity.

 

[bcps]

I think he wanted to buy one that had the proper inverter (built in) to
the
unit.
After all. I would much rather buy units that are, ready to run off of 12
volt DC with the correct inverter built in then to have to add an inverter
and all the problems that come with it...MSW or TSW inverter and start up
power needed for unit etc.
Exactly!

If you say it will run off of 12 volts DC. than all you should have to do,
is use the right gauge wire (as stated by the mfg.) and it should work.

Not too much to ask is it?

Found one
http://www.3rivers.net/~cmac/m-1.htm

but my wallet had a heart attack when it saw the price.

Guess I'll stick to propane for a while longer.

BTW. I have a 12 volt 1500 watt microwave oven...all you need is a proper
12 volt to 110 volt inverter to run it....
See where this is going?

Hehe, like in Back to the Future.... the time machine is electric, but it
requires nuclear fuel.

 

[Larry Klein]

bcps wrote:

Found one
http://www.3rivers.net/~cmac/m-1.htm

but my wallet had a heart attack when it saw the price.

Only 600 "RATED" watts.
Hardly worth it.

Guess I'll stick to propane for a while longer.

Nothing like a cheap charcoal grill and a few moistened bags of cherry
wood for authentic smoke flavor.

 

[T. Keating]

Found one
http://www.3rivers.net/~cmac/m-1.htm

but my wallet had a heart attack when it saw the price.

Guess I'll stick to propane for a while longer.

Get yourself one of the Panasonic inverter models.. ~100$
They'll efficiently run on MSW output(*) and can vary power
consumption proportionally to setting..

My.. Pana runs from 1850 watts consumption(max pwr S10) down to
430watts(S3).. Settings S2 and S1 vary the on/off duty cycle @430
watts.

(*) Front end power supply on inverter models convert AC back into
HVDC via diode bridge and capacitors, essentially it's a switching
power supply and remains unaffected by the poorly approximated AC
waveform output many transformer based MSW inverters(tripplite, ??).
(Ground really needs to be connected to neutral to run a Microwave
unit..)

 

[Rex Handly]

Samsung make a true 12v and 24v microwave 550w (from memory)

 

[Larry Klein]

**** the bottom feeders. Most are mental midgets and have OCD
problems.

Microwave ovens require high voltage to run the magnetron and thus an
inverter is required to convert the 12vdc to about 5kVdc.

All well and possibly true, but top posting is still the sign of an idiot.

 

[Randy]

My batteries are less than 5 feet away from where I would intend on
putting the oven. My point was that they claim the oven operates at 12
volts with no need for an inverter, but an inverter is included with it in
all the products I've seen. For example:

http://www.roadtrucker.com/feature-12-volt-microwave.htm

I already have a small 120vac microwave. If there is no such thing as a
true, stand alone, 12 volt microwave, then I should probably just upgrade
my inverter and forget about it...

That is what I did only I upgraded everything.
4 Wal-Mart RV deep cycle batteries (the largest they had) in series/
parallel arrangement, Outback FX2524 inverter and two Photowatt 80 Watt
panels.
Its a darn expensive way to warm up a cup of coffee but it works great.

 

[bcps]

That is what I did only I upgraded everything.
4 Wal-Mart RV deep cycle batteries (the largest they had) in series/
parallel arrangement, Outback FX2524 inverter and two Photowatt 80 Watt
panels.
Its a darn expensive way to warm up a cup of coffee but it works great.

Please tell me you are doing something else with that setup other than
warming a cup of coffee.

 

[Randy]

Please tell me you are doing something else with that setup other than
warming a cup of coffee.

It is amazing the silly things we do with this stuff.
Watch a DVD on the Big screen, power up a cool display on the lava lamp but
most generally run the washing machine, fans, the George Foreman grill,
light a few lights here and there and a occasional run of the skill
saw/drill.
I am a little short on panels to do much refrigeration but it's all about
how you want to use your power. I do have two more 80 watts coming, more
power!
My Cell phones and other 12 volt lights are on my older 60 watt 12 volt
system which dose quite well. It can run a 750 watt MSW inverter to run a
small inefficient bar fridge for about 4 hours in a pinch (in case of a soda
pop emergency)
Sorry if I sound a bit nutty but this is a fun hobby for me since I also
have the seperated grid
If only I had the money for panels to run the cenral air.
Have a good day!