The power rating of a switch is the maximum power (in Watts) that it can handle without exceeding its operational limits. All switches above are rated at 10 KA when protected by any UL Listed CB Quick-make, quick-break operating mechanism that ensures positive operation. Visible blade, double-break switching action. Switches are designed for use at an amperage and voltage not higher than the limits stated in the data sheet or stamped onto the housing/mounting yoke. Oil rigs, railways, manufacturing plants, and similar applications require industrial-grade network equipment that can tolerate an extended range of temperature, humidity, vibration. Lets say that we have a switch that its max ratings are 3A/250V AC. So if we connect it directly to source it will handle up to 3 A * 250 V = 750 W.
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