I bought a TV from a thrift store and didn't realize it was missing its power cord. The label on the TV says 100–250V, 50/60Hz, and 1.5A. I found an ONN replacement cord rated for 125V, 10A, and 1250W. I'm in the US and want to make sure the voltage and amperage ratings are safe, assuming the connector fits the TV.
4 Answers
Check both ends: it needs to plug securely into a standard US wall outlet and fit the TV’s power inlet. Common TV connectors include the figure-eight style and the three-slot computer-style connector. If the shape matches properly and it isn’t loose, the electrical ratings are fine.
The TV’s 100–250V, 50/60Hz input range includes the roughly 120V, 60Hz power supplied in the US. The cable’s 125V rating also matches that supply. The higher amperage rating on the cable is not dangerous; it indicates the maximum current the cable can safely carry.
There’s no need to worry that the cord’s higher amp rating will cause a fire. Electrical devices draw the current they require; the cable rating is simply its safe limit. Don’t use it if the plug or TV connector only partially fits, feels loose, or requires forcing.
The cord’s 10A rating won’t force 10 amps into the TV. The TV draws only the current it needs, up to its rated 1.5A. A 125V, 10A cord is suitable for normal US household power, as long as the cord’s connector matches the socket on the TV.

I’m buying it in person and have compared the connector with the TV’s socket. It definitely looks like the right shape.