[syarring]

If the wire gauge to a machine is changed, will the voltage/amperage to the machine automatically change? Or does it matter what the machine actually uses?

In my case, the amperage was already much lower than the original wire gauge, but now the wire gauge will match better with the actual usage.

Thank you!

[Capuchin]

Hi, this has nothing to do with energy, please take care to place your questions in the correct forum in future. Thank you.
I am getting a moderator to move it for you now.

[Stratmando]

Are you talking about reducing the size of wire, smaller than the manufacturer?
Or are you talking about wire in machine smaller than wire feeding it?
There is also starting current. What is machine?

[labman]

As long as the wire size is still adequate, the machine will still draw the same amperage and the same voltage. If the wire is undersized, the voltage will go down and the amperage up. And yes you need to allow for start up.

Once when I specified #14 or larger for a pump drawing about an amp, a nitwit in purchasing told me #14 wasn't large enough for 480 volts.

[syarring]

Are you talking ... What is machine?

My question was for the supply power to my machine.
The machine is a radio frequency sealer.
I think the actual usage is around 40 amps at start-up of the cycle (208 vac 3-phase power).
Of two identical machines in my plant, one is supplied with #2 wire, 100 amp breaker, and the other is supplied with #6 wire 60 amp breaker.

[edtech87]

The circuit breaker is there to protect the wire, not the equipment. If there is a fault in the feed to the machine or in the machine itself, the breaker is in place to prevent the fault from causing your wire to catch fire and burn your building down. The breakers mentioned above ( 100A for #2 and 60A for #6 ) are properly sized to prevent faults from overheating them. Beyond that, machines that operate on less than, or more than the specified voltage do not operate efficiently and will fail prematurely. Typically, rotating machines have large start currents and may need to step down the wire gauge so the voltage does not drop excessively.

[donf]

Ed,

This thread was opened in 2007.

Because of the new skin, we have to be careful about answering dead items. :)

[tkrussell]

I know this is an old thread.

However, a new answer, that I must comment on:

may need to step down the wire gauge so the voltage does not drop excessively.

Step down the wire?

Confusing advice.

I would say step up, if I had to use the same terminology.

Better said, increase the wire size to reduce voltage drop.

[edtech87]

When I wrote step up wire gauge it looked wrong, so better said it should read "increase wire size" instead of "step down wire gauge". The problem is misunderstanding the function a fuse is suppose to perform.