As we know, the key parts for a revolving door including the Inverter (also called frequency transformer), PLC, Logo power, Relay, Encoder etc.., what they are used for ? Please check the following part for reference. 

The Inverter is the device that to control an AC motor by changing the frequency of the working power supply, which could be simply understood that the motor speed will became bigger or smaller when the power frequency was changed .To us, the common used brand for revolving door are SIEMENS and LENZE which both are the top brands in the inverter industry .  

The PLC (Programmable Logic Controller) is the brain for a revolving door, it could collect all the information from the detective devices, then process the information and give the feedback to the revolving door to do the suitable activity like revolve, stop, run quickly or run slowly etc..

Logo Power is the electrical device that could convert alternating current into direct current for stable output.

The Relay. To the revolving door, the relays could monitor the safety device, like safety rubber, foot sensors etc., to judge they are normal or damaged, which is a big help for the door maintenance .

The Encoder. It's the biggest feature of our revolving doors, most of other Chinese brands didn't assemble this device. The biggest use of the Encoder is the positioning, it can process the pulse and electronic signal, then to realize the positioning. 

Hope the content above is hepful to you .