A rheostat is in a simple series circuit with another component. The input is connected to one end of the rheostat. The output is taken from the wiper terminal. Some schematics show the remaining other end of the rheostat left unconnected and others show the wiper and remaining terminal connected together. Is there any advantage of one way over the other?
Red
If the wiper ever hits a "dead spot" where it would go open circuit, then having it also connected to the far end of the pot means that the max resistance is limited to the total value of the pot vice a completely open circuit.
Just paranoia. If the wiper should fail you would still have the full R in the circuit.
Chuck P.
Please consider this trivial if you must but, in the middle of the last century, when I was taught electronic fundamentals, a rheostat was considered a two terminal device. A potentiometer, the term I believe you wish to use, is, in its most basic form, a three terminal device.
Please do not let this detract from the fine and accurate answers you have already received.
It doesn't have to fail -- just momentarily lose contact (think wirewound).
Point taken with grace. Although technically a pot, since I am only using 2 terminals it is being used as a rheostat. Plus having the diameter of a cup & rated at 1A, it just looked like a rheostat so that's how I referred to it. My mistake. Thanks to all who responded.
Red
Good point.
Chuck P.
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