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Posted By: newsgraphics US appliance in Brazil - 11/29/09 01:49 PM
My wife's family is from Brazil and we are planning to bring a panini (sandwich) maker from the U.S. In the part of Brazil where her family lives, the electric system is on basically the same standard as the U.S. (110 volt, 60 Hz, compared to 120 volt, 60 Hz U.S. standard). The only difference is the lack of grounding, and often outlets are not polarized either. They use hybrid outlets that accept both Type A ungrounded NEMA plugs and Type C Europlugs.

This particular appliance is equipped with a 3-prong NEMA plug. If we bypass the ground and polarity with an adaptor, I assume that there would be no additional safety hazard, because the chassis would have been wired to the ground prong (as opposed to a 2-wire polarized design where the chassis is sometimes wired to the neutral line, and reversed polarity could be deadly). Ungrounded, the metal chassis on this sandwich maker should essentially be isolated (in the absence of a fault condition.)

Does anyone see any issue with bringing this appliance? Keep in mind that we can just as easily buy one there (for 5x as much) and it will have a 2-wire unpolarized Europlug. I can't imagine that buying an appliance from there would give us any extra measure of safety over just bypassing the ground on a U.S. appliance.
Posted By: newsgraphics Re: US appliance in Brazil - 11/29/09 02:17 PM
I wanted to clarify one statement above... Obviously a chassis wouldn't be connected to the neutral line by design, however in the event of a fault between the neutral and the chassis, the chassis would become electrified even if the device was off, should the polarity be reversed.
Posted By: Texas_Ranger Re: US appliance in Brazil - 11/29/09 05:50 PM
There are two approaches towards ungrounded wiring, internationally. One, mostly used in Japan, is double isolation of appliances, i.e. no exposed metal parts that could become energized, even under fault conditions.

The other one is isolated rooms, i.e. rooms that don't provide any exposed grounded metal surfaces, thus even in case of a line to case fault in a metal cased appliance the ground path cannot be completed and humans or animals are not in danger. This allows for safely plugging appliances that should be grounded into ungrounded receptacles. Used to be most common in Germany prior to the advent of hot water central heating systems, taking exposed metal surfaces bonded to ground (pipes and radiators) into every room (hot water is the most common type of central heat all across Europe).

The third possibility is a system without ground reference, i.e. floating delta, where the ground path can't be completed either.

So, without knowing the exact details it's impossible to give a 100% safe answer.

However, considering the shape of most wiring in Brazil, most Brazilians couldn't care less about such issues I guess.
Posted By: newsgraphics Re: US appliance in Brazil - 11/29/09 10:12 PM
Thanks for the info, Texas_Ranger. If you have never been to Brazil, you would probably be shocked (no pun intended) at their electrical code. While the country is finally bringing things up to North American standards, it is going to be decades before those standards are common in most existing homes. Grounded outlets are just becoming mandatory in new construction, for example. Homes don't have central water heaters like in the U.S., so showers are equipped with electric heated shower heads. These are powered by (often ungrounded) 220 volt leads coming right out of the wall above the showerhead. There are no GFCIs used anywhere either. Outlets are often located right above sinks, and kitchen sinks often have 220v "water heaters" on them as well.

A good solution that I thought of might be to bring along a plug-in GFCI to use with the device.
Posted By: IanR Re: US appliance in Brazil - 11/30/09 06:41 AM
If you have to render the ground inoperative like that, I would say putting it on a GFCI should be mandatory, as far I was concerned. Remember, even the NEC allows putting a grounded outlet on a non grounded circuit if it is a GFCI and is clearly marked "No Equipment Ground"
Posted By: Texas_Ranger Re: US appliance in Brazil - 12/01/09 10:37 PM
I've seen enough pictures, so I'm not too surprised... that's what my last sentence was trying to express, politely wink

On a side note, electric tankless water heaters are commonly installed inside showers in Germany, as are wall-mount tank water heaters. Of course with an appropriate IP rating (waterproof) and proper feed. Gas fired combined central heating boilers/ water heaters (combi boilers) are commonly found above bath tubs all across Europe and theey have pumps, electronic controls and everything running on 230V (or an internal stepdwon transformer for the electronics of course).
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