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Posted By: pkc Max.Total Amp. For Double Socket (US/Canada) - 03/25/05 04:57 AM
I have a proposal to make available in US and Canadian household electric heaters at 120V (each heater with two independent electric heating elements) with the two heating elements operating at the same time and together producing a total output of 2400W-3600W and accordingly drawing a total electricity current of 20-30 amperes at 120V (10-15 amperes for each heating element).
Based upon the US or Canadian Building Codes and in the usual settings for US or Canadian household electrical wiring for 120V : (a) What would be the ampere rating for the electrical wiring connecting a household wall double socket assembly to the main fuse or circuit breaker? (b) What would be the maximum ampere that can be drawn from each one of the two sockets in household wall double socket assembly? (c) What would be the total maximum ampere that can be drawn from both sockets together (operating at the same time and serving the two independent heaters or heating elements) in a household wall double socket assembly? (d) How many 20 or 30 ampere single sockets (from which a total 20 or 30 amperes can be drawn) are usually installed in a US or Canadian household and, if so, where would these 20 or 30 ampere single sockets be usually located or installed in the household? (e) Would 20 or 30 ampere single sockets be installed or located on the patio or garden of such US or Canadian household? (f) Are there any other perceivable safety hazards or reasons against operating two separate heating elements simultaneously both drawing electricity current from the same wall double sockets, apart from electricity current overload (assuming the total current drawn from such wall double sockets and through the electrical wiring connecting the wall double sockets to main fuse or circuit breaking is within UL rating)? Your assistance in these matter will be much appreciated.
These heaters seem too powerful for the US Market, there are no 30 amp 120v receptacles in a typical house.

I suggest you start your research by contacting UL >> www.ul.com or similar recognized testing organization.
That much heat in such a small package is a recipe for disaster... FIRE.

With that said, the only way to get what you want would be to design it to plug into a 4-wire dryer receptical. These provide 120/240v at 30 A. This is assuming that such a device would be portable and cord & plug connected. If hard wired, then obviously this wouldn't apply.

But I stil maintain (and I bet most would agree) that is a fire risk. Even 1kW or 1.5kW electric heaters are a risk, so I seriously think if anyone needs any more portable heat than than that, they should seriously talk to an HVAC contractor and get their household heating beefed up through better central heating.

[This message has been edited by jdadamo (edited 03-25-2005).]
Posted By: pkc Re: Max.Total Amp. For Double Socket (US/Canada) - 03/25/05 05:58 PM
Thank you for your prompt and informative responses. I shall contact UL accordingly in regards to the heaters. In the meantime, your answers to my questions posted would certainly enlighten me further on this topic.
This sounds like Phil from the newsgroups.
No Phil. Nobody here has heard of a duplex 5-20 with a 40a rating either.
Posted By: pdh Re: Max.Total Amp. For Double Socket (US/Canada) - 03/30/05 10:33 PM
The Phil from the newsgroups is pdh, not pkc. If I needed a heater that powerful, I'd run it via 240 volts.
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