No-load current of the motor
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How is the no-load current of a motor determined? Our motor is 15KW; why is the power supply only at 2A? Is this normal?
The no-load current of the 1# l-zhi-q motor varies for motors of different power levels and at different rotation speeds. Generally speaking, motors with lower speeds have a larger value; those with higher power have a relatively lower rated current. No-load current is a key parameter that reflects the efficiency of a motor, so the lower this value, the better. You just need to check that the three-phase voltage and current are symmetrical; if so, there is no problem. It should be noted that when using a clamp ammeter to measure small currents, the error is relatively large, as the measurement is affected by the surrounding electric fields.
The explanation on the 2nd floor is quite detailed. Generally, it’s like this: first of all, the three-phase currents are fairly accurate, with no significant deviations. I’ve conducted tests in our company, and generally the no-load current is around 15%
A 15KW motor shouldn’t have only 2A of current; there must be some problem somewhere, and the ammeter is the most likely culprit.
http://bbs.hcbbs.com/viewthread.php?tid=551897&page=1#pid3098106 We measured the operating current to be 24.5; there should be no problem with the ammeter
The no-load current of a 15KW motor is 2A. It’s abnormal. What did you use to detect it? Are the three-phase currents balanced? The no-load current should be around 7~8A.
Is the control power supply only 2A? I don’t understand; the control current has no direct relationship with the main circuit current. Typo?
A 15KW motor having an no-load current of 2A is absolutely incorrect! The no-load current should be around 6~10A.
No-load current is the excitation current; once the motor is manufactured, its technical parameter—the no-load current—is determined
The current in the control circuit is already very low. But I don’t know exactly how much. The load on the control circuit is at most the thermal relay, plus the power consumption of a few auxiliary relays; theoretically, it should be in the watt range. . . There are also indicator lights and such; the load is very low, so to speak. A control circuit is one that uses a low-current circuit to control and protect the high-current main circuit: lol 2A of current isn’t really considered low.
2A is very small; 15 (KW) * 2 * 15% = 4.5 (A). There might be some problem somewhere!