Here is an expanded introduction in English based on the provided information:

Omron ID Sensor Unit C500-PS221

*Microwave Type for Long-Distance Use*

The Omron C500-PS221 ID Sensor Unit is designed for long-distance microwave-based identification and data communication. It can be used to read out newly occurring errors or statistical error information. When inserted into a dedicated keyboard attached to a portable process control computer, the unit functions as a specialized tool for system diagnostics and maintenance.

In the event of communication anomalies, or when communication testing is required during system startup, this unit demonstrates its effectiveness by enabling quick error diagnosis and verification. The information displayed on the process control computer can be selected between English and Japanese, with language settings configurable via the DIP switches on the ID sensor.

The system supports the construction of an ID system incorporating both short-distance electromagnetic coupling and long-distance microwave communication methods. It is capable of reading and writing up to 502 bytes of data. An integrated error recording function allows the unit to store newly occurring errors encountered during communication with data carriers, retaining up to 30 error records. The details of these errors can be accessed and reviewed using the portable process control computer.