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A Variac is a fancy type of transformer: it controls the amount of electricity flowing to an appliance. They are used in the organic chem teaching labs to control heating mantles - never use a heating mantle without a Variac!

Variacs are quite heavy. If they are dropped on the floor or the lab bench, they will break. Each one costs about $225. Please handle them with care.


How to unplug a Variac, and in fact all electrical equipment:

The picture below shows the proper way to unplug a Variac. Firmly grasp the plug (not the cord!) and pull it from the socket. If you pull it by the cord, you might pull the cord out of the plug. This damages the cord, bares the wires, and makes the unit useless. It can be repaired, but it is time-consuming. Also, often damaged cords remain in use before they are reported as in need of repair, and an unsuspecting student might get an electrical shock if they touch the bare wires next to the plug.

Right and wrong way to unplug equipment

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