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Name: Kimberly
Status: other
Age: 30s
Location: N/A
Country: N/A
Date: 1999 

I've been told that a machine running on 110V has a certain look to the plug and a machine running on 220V has an entirely different plug.

However, my new coffee grinder says it runs on 220V but the plug looks like a 110V plug not like the plug like my dryer. What is a sure way to know if a machine would run on 220V as opposed to 110V?

Most probably it works on both voltages, 110 and 220. This is quite common these days. I have a battery charger for my lap top which has a 110 V plug but with can also work at 220 when I am travelling abroad. I use an adaptor to access the 220 V receptacles. How can you know for sure, well perhaps reading the instruction booklet but the appliance will not be hurt by using the lower US voltage, using the higher voltage-if not rated for such- will of course cause the appliance to burn out.

Dr. Myron

Some devices such as many consumer electronics are sold worldwide and may carry dual voltage capability. This means that the unit automatically senses and adjusts to the supplied 120/220 voltage. For these units, there are simple adapter plugs so that you plug the unit into the electric outlet overseas.

In the US, there are standard plugs for 110 and 220 so that they are not confused. There are other plugs for industrial machinery as well. Your grinding machine (if not industrial) is probably dual voltage, and if so, you can use it here and abroad with a simple adapter plug. The best way to know what voltage to use is to read the information that appears on the back of the unit.

Dr. Ali Khounsary
Advanced Photon Source
Argonne National Laboratory
Argonne, IL 60439

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