The inverter no-load current is greater than the load current

motor lamination three phase induction wound rotor 

Specifications
1. Lamination of electric motor 
2. IP54 class F 
3. 100% copper 
4. silicon steel stamping 

5.stunning performance 
A 75 kw micro can WIN - G9 inverter commissioning the strange phenomenon Cause: a cement plant users to send a 75 kw can WIN - G9 frequency converter, the cause of the problem is, in the operation of the fire smoke in the inverter, the inverter downtime. Check, the power input circuit of the machine for three phase half controlled bridge, using the principle of controlled rectifier, on the main loop of the dc energy storage capacitor "soft power" and save the small power inverter commonly used rechargeable contactor. In fact half controlled bridge in this here is equivalent to non-contact soft blunt electricity switch. Inspection found that one of the thyristor module electrical motor 12v 1000w terminals have obvious signs of flashover arc burning, but the measurement is not short circuit. Found in the disassembly easily fixed nut landed, flashover reason seems to be a connecting screw loose, causing poor contact. The module for a combination of a diode and a one-way thyristor. And then check the control panel and inverter main circuit, without exception. The module, more than two phase half controlled bridge as the ac electric motor power input, after power on, with a small power 2.2 kW three-phase motor, feel no problem, switch to the new module after a same model, then to the site for installation. 


115/120 V AC Voltage and Three-phase Phase small 240v electric motor
Specifications
1.Specifications1.3-phase asynchronous motors 
2.IEC standard 
3.OEM 
4.Voltage:50HZ &60HZ;380V&415V 

5.Protection class: IP54 
Precaution, first will run to 5 hz frequency, frequency converter load as a fan, motor connector off first, make the motor no-load running. This trial run, got a fright! Frequency at 5 hz, no-load running current 45 a, although feel slightly larger, but consider for a possible repair, or frequency converter for motor winding parameters such as starting curve or torque compensation made adjustment caused by waiting for a reason, without notice. When up to 10 hz inverter panel shows the current and the output current is measured with clip-on table, have reached the 100 a! And the oscillation amplitude of the output current is great, but test the three-phase output voltage, about 70 v, balanced and stable. The motor cable release, electric logging on the inverter output, output frequency 10 hz, the output voltage is 70 v, 20 hz to 150 v, 35 hz to 250 v, after decreasing with frequency, to 50 hz, 400 v. In this process, the measurement of three-phase output voltage balance is very good. The inverter output of V/F curve electricalmotor1.blogspot.com accords with quadratic load torque characteristics. No problem. Output voltage balance and stability, and the output current is too large and the current volatility, obviously for the load caused by abnormal. This is lead to the conclusion of conventional judgment.