[imautoparts]

My question is, since the appliance being operated is only 5 or 6 watts, can I just design it to use both plugs of a 110 outlet and reverse the wire polarity of one set of wires?

If this isn't viable, could I do it with one local plug and an extension cord to the next circuit in the home?

No, I'm not a nut. I have a legit invention but efficiency is much much better on a 220V two phase feed. My background is automotive engineering, so feel free to be technical. Thanks.

 

[k_buz]

Why would you design it to use 240V with only a 5 or 6 watt load? You are restricting the ease of use.

I admit that I have no idea what your invention is, but if it is for the home, you will want to design it to run at 120V.

 

[jbfan]

No to both.
The only way you can change a 120 volt receptacle to 240 vplt is if it is a dedicated receptacle.

 

[imautoparts]

So it is a dedicated rewire either way. Can't kill all other loads in a typical house circuit. That won't work since most homes have the overhead bedroom or wall switch lights on the outlet circuits.

Hmmm. Obviously I need to improve the efficiency of a 110V system. Thanks.

 

[Wildie]

My question is, since the appliance being operated is only 5 or 6 watts, can I just design it to use both plugs of a 110 outlet and reverse the wire polarity of one set of wires?

If this isn't viable, could I do it with one local plug and an extension cord to the next circuit in the home?

No, I'm not a nut. I have a legit invention but efficiency is much much better on a 220V two phase feed. My background is automotive engineering, so feel free to be technical. Thanks.

Are you in North America? If so 2 phase won't be available! All the power generated is 3 phase and if you use just one 3 phase leg its a single phase.
You could convert a receptacle over to 220 volts as long as there are no other outlets on the circuit. It would require a 2 pole breaker to be installed in the panel.
Its possible to purchase a step up transformer to convert 120 to 220 volts. With this arrangement, your invention could be plugged in anywhere.

 

[diystephen]

Watts are watts (whether 120 or 240VAC.) The difference will be the amperage flowing.

6 watts @ 240VAC = .025A
6 watts @ 120VAC = .05A

What do you mean when you say 240 makes the device more efficient?

 

[ddawg16]

Watts are watts (whether 120 or 240VAC.) The difference will be the amperage flowing.

6 watts @ 240VAC = .025A
6 watts @ 120VAC = .05A

What do you mean when you say 240 makes the device more efficient?

My thoughts as well......

At that low of a wattage, you could run it off 12Vdc and still not have issues with efficiency.....

 

[dmxtothemax]

My question is, since the appliance being operated is only 5 or 6 watts, can I just design it to use both plugs of a 110 outlet and reverse the wire polarity of one set of wires?

If this isn't viable, could I do it with one local plug and an extension cord to the next circuit in the home?

No, I'm not a nut. I have a legit invention but efficiency is much much better on a 220V two phase feed. My background is automotive engineering, so feel free to be technical. Thanks.

Sorry ! your idea will NOT work !

Unless you have TWO hots available in your panel.

Two sources of 120v from the one source wont work.

You could use a transformer thou.

 

[mpoulton]

If you have a 6W load that requires 240V instead of 120 for "efficiency", then you need to re-engineer it (or maybe not re-engineer, but simply engineer it in the first place). There's no good reason for a 6W device to require any particular supply voltage. What is it?

 

[imautoparts]

mpoulton If you have a 6W load that requires 240V instead of 120 for "efficiency", then you need to re-engineer it (or maybe not re-engineer, but simply engineer it in the first place). There's no good reason for a 6W device to require any particular supply voltage. What is it?

It is a radiant heater that utilizes a unique new ceramic to provide directional, radiant warmth at high frequencies (infrared). My prototype units all utilize the 240V that my home has in every room - as it was built with embedded ceiling heat when new.

I designed a replacement electric radiant element using the new ceramic and when installed it looks like crown molding, but radiates sufficient heat to heat any room up to approximately 15' X 12'. And it isn't 6 - 8 watts, it is 6-8 amps on a 20A dedicated 240V line-in. This amp reading was gained by using a non-contact voltage tester.

I've not yet thoroughly researched heat output per amp and/or different metallic conductor materials at the 120V level. Since I've not studied AC since school 35 years ago any input would be great.

Any and all thoughts are welcome - thanks!

 

[rjniles]

. And it isn't 6 - 8 watts, it is 6-8 amps on a 20A dedicated 240V line-in. This amp reading was gained by using a non-contact voltage tester.

You were the one that said 6-8 watts in the first post.

How do you measure amps with a non-contact tester?

 

[k_buz]

Actually he said 5-6 watts.:whistling2:

 

[AllanJ]

If all this device requires is 6 watts at 240 volts then the manufacturer will redesign it with a built in step up transformer or other power supply circuitry to obtain the 240 volts. At that usage level (wattage) a transformer is not prohibitively expensive or heavy.

Way back when, radios and other electronic equipment used vacuum tubes many of which used 240 volts or more. Transformers, with multiple windings to provide a variety of voltages typically ranging from 6 to 480 (high 4 figures or 5 figures for televisions), were part of their internal power supplies. (There were some smaller items, notably radios, that required no more than 120 volts and contained lower voltage components wired in series so as to require no transformer, step up or step down.)

 

[SuperJETT]

How do you measure amps with a non-contact tester?

clamp-on ammeter.

To the original poster, you really threw people off, including myself, when you said 5 or 6 watts.

Very few houses built nowadays have 220V in each room.

If you do redesign for 110V, you will have double the amps you had at 220V for the same heat, which most likely puts you at requiring 20amp circuits which could be an issue also.

 

[ddawg16]

Ok.....now that we understand what he is doing......240Vac @6-8A....

As I undstand the 'original' question....can he grab the hots off two different 120Vac plugs (it's not 110) and get 240Vac...I'm assuming that he wants to do this just for 'testing' purposes.

Well....the only way that will work is if the 2 different 120Vac plugs are on different legs of the house power like a MWBC. The only way to know is to measure from the 120vac leg of one outlet to an adjacent plug. But considering that most rooms are wired typically on the same ckt....I doubt he will find one unless he just happens to luck out.

 

[chitownken]

.... and when installed it looks like crown molding, ........

Not many homes have outlets of any kind near the ceiling and I doubt that very many people would want a cord hanging all the way down the wall.

 

[diystephen]

It is a radiant heater that utilizes a unique new ceramic to provide directional, radiant warmth at high frequencies (infrared). My prototype units all utilize the 240V that my home has in every room - as it was built with embedded ceiling heat when new.

I designed a replacement electric radiant element using the new ceramic and when installed it looks like crown molding, but radiates sufficient heat to heat any room up to approximately 15' X 12'. And it isn't 6 - 8 watts, it is 6-8 amps on a 20A dedicated 240V line-in. This amp reading was gained by using a non-contact voltage tester.

I've not yet thoroughly researched heat output per amp and/or different metallic conductor materials at the 120V level. Since I've not studied AC since school 35 years ago any input would be great.

Any and all thoughts are welcome - thanks!

In this case efficiency isn't going to be greater with 240VAC, but the amps will be lower (and you can use smaller wire.) You will want to use 120VAC if you want any mass appeal/ease of use. Here's the numbers:

240VAC @ 8A = 1920W
1920W/120VAC = 16A

240VAC @ 7A = 1680W
1680W/120VAC = 14A

240VAC @ 6A = 1440W
1440W/120VAC = 12A

As someone else mentioned, this is likely to need a dedicated 20A circuit @ 120VAC. You will also want to verify the amperage reading using a multimeter in series.

 

[mpoulton]

It is a radiant heater that utilizes a unique new ceramic to provide directional, radiant warmth at high frequencies (infrared). My prototype units all utilize the 240V that my home has in every room - as it was built with embedded ceiling heat when new.

I designed a replacement electric radiant element using the new ceramic and when installed it looks like crown molding, but radiates sufficient heat to heat any room up to approximately 15' X 12'. And it isn't 6 - 8 watts, it is 6-8 amps on a 20A dedicated 240V line-in. This amp reading was gained by using a non-contact voltage tester.

I've not yet thoroughly researched heat output per amp and/or different metallic conductor materials at the 120V level. Since I've not studied AC since school 35 years ago any input would be great.

Any and all thoughts are welcome - thanks!

OK, so it's 1440-1920W, rather than 5-6W. 1920W is the maximum allowable continuous load on a 20A 120V circuit, so you could implement this in a 120V version as well. It is trivial to make a heating appliance work at a different voltage. Whatever the resistance is at 240V, you need 1/4 of that resistance to obtain the same wattage at half the voltage. Most permanent space heating is 240V to save on wire cost, though.

Make sure you include overtemperature cutouts in each unit.

 

[rjniles]

clamp-on ammeter.

Not what I :jester:think of when someone says a non-contact tester, but it fact you are correct.

 

[SuperJETT]

Same here, I think of something like this