Without PLC control, frequency conversion can also work independently:


The situation of joint control of PLC and frequency conversion:

1. The inverter can accept 4~20mA analog signal output from PLC to realize frequency adjustment.

2. High-end inverters can also form network communication with PLC


The case of frequency conversion working independently:

1. Use the handheld operator on the frequency conversion panel to adjust the frequency and open-loop control.

2. The frequency conversion can accept the analog signal of the controlled quantity on site is also 4~20mA, which forms a closed loop with the output frequency signal and is controlled independently.

3. In fact, many frequency converters can complete the on-site frequency closed-loop adjustment independently from the PLC, but it must be explained that since the PLC is often the control center of the on-site control system, the main task of the frequency converter is to perform functions, so it cannot be independent from the PLC control system operate.