【Daily Question】Question from Issue 20151118
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Participation reward: 2 Wealth. Reward for correct answer: 9 wealth. The rated current of AC contactors varies with different rated voltages ( ). A. The same B. Different C. Independent of voltage D. Proportional to voltage 【Production and Management Division】Seeking moderators and technical discussants to join
The rated current (B) of AC contactors varies with different rated voltages.
For AC contactors, the rated current varies (is different) at different rated voltages.
The rated current of AC contactors varies with different rated voltages ( ). B, not the same
The rated current (B) of AC contactors varies with different rated voltages. A. The same B. Different C. Independent of voltage D. Proportional to voltage
The rated current (B) of AC contactors varies with different rated voltages. A. The same B. Different C. Independent of voltage D. Proportional to voltage
The rated current (B) of AC contactors varies with different rated voltages. A. The same B. Different C. Independent of voltage D. Proportional to voltage
B. Not the same. －－－－－－－－－－－－－－－－－－－－－－－－－
Answer: B (not the same). 1. For AC contactors of the same model, their rated currents differ when they disconnect loads under different voltages; in other words, the power they can handle under different voltages varies. 2. For example, if the same AC contactor can drive a 18KW device at 220V, then it can only drive a load of around 30KW when used at 380V (since the current required to drive a load at 220V is higher than that required for a three-phase motor with balanced voltage across its phases). 3. Another example: if the same AC contactor has a rated current of 63A when used at a rated voltage of 380V, then its rated current drops to around 40A when used at a rated voltage of 660V.