How to set the gearbox ratio in the 6SE70 inverter - News - Global IC Trade Starts Here.

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There has been a change in the gear ratio of the motor's gearbox. Previously, the ratio was 2.33, but it is now 2.8. This raises the question: do we need to adjust the gear ratio setting in the inverter parameters? I checked the parameter "gearratio" under U802 in the vector manual, but noticed that our inverters are all set to the value "30" by default. It seems like this parameter isn't being used at all. So I'm not sure if it's even active or how it should be configured.

From what I understand, the PLC controls the inverter by sending signals such as the main control word and speed reference. If the system is operating in speed control mode, the actual motor speed is determined by the speed reference from the PLC. However, since the gear ratio has changed from 2.33 to 2.8, the final output speed will no longer match the original settings if nothing is adjusted.

This means that the speed reference from the PLC must be recalculated or modified accordingly. Alternatively, you can adjust the inverter's internal parameter P444 to reflect the new gear ratio (P444 = 2.33 / 2.8). Either way, the current setup won’t provide accurate results without some form of correction. It’s important to verify this during testing to ensure the system operates as intended.