Do not overload an outlet by plugging in...

[Tofu]

Hello Alan, Mister Micawber, Beeesneees, Mordant, Esl_Expert and other native English speakers,

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Do not overload an outlet by plugging in the refrigerator and other appliances at one time; otherwise, a fire may occur.
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Are there any errors?

[Mordant]

It's fine.

[Tofu]

Thank you, Mordant.

Is "at one time" unnecessary?
Does "another appliance" sounds better than "other appliances"?

[Mordant]

"At one time" may not be necessary, but it's often helpful.

I can sing and dance.
I can sing and dance at one time.

I am sure you can see that those sentences don't have to mean the same thing.

I like "other appliances." Either works.

[Tofu]

Thank you, Mordant.