117V AC appliance on 127V AC mains?

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Using a 117V AC appliance on a 127V AC mains in Brazil can be safe, depending on the actual voltage fluctuations. The mains voltage can vary between 114V and 139V, which may exceed the appliance's tolerance. If the appliance is rated for 117V with a tolerance of ±10%, it can safely operate between 105V and 128V. However, to ensure safety and protect the appliance from potential overvoltage, using an auto-transformer is recommended. Overall, checking the equipment ratings and considering voltage variations is crucial for safe operation.
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In parts of Brazil, the mains voltage is 127V AC. Is it safe to use an appliance which is supposed to take 117V AC in this situation?
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You would have to check the ratings of the equipment.

If the mains is a nominal 127 volts, this may mean 127 volts plus or minus 10 %.
So, you could get voltages between 114 volts and 139 volts. (In many places it could be worse than that, of course, but this is just looking at the ratings)

If the equipment was rated at 117 volts plus or minus 10 %, this would mean it would be safe to operate it between 105 volts and 128 volts.

So, it would depend on the actual voltage available. If the mains were always on the nominal voltage or on the low side of it, you would be OK.

To be safe, you should probably be using an auto-transformer to reduce the voltage.
 
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