The legacy dataset contains the most useful information of each IMU module in one convenient table. The legacy dataset is available in the registers 12000 to12165. It can be read with two read requests.
Each IMU module updates the values in the dataset registers on a regular basis.
The response time of requests to legacy dataset registers is shorter than the response time of requests to device registers. Therefore, it is recommended to read the legacy dataset registers instead of device registers, to improve the overall performance of the system Modbus Programming Recommendations.
The legacy dataset is compatible with legacy versions of the MicroLogic trip unit for ComPact NSX, PowerPact H-,J-, and L-frame, ComPact NS, PowerPact P-, and R-frame or MasterPact NT/NW circuit breaker. For this reason, data read directly in the Modbus registers is organized in a different way than in the standard dataset.
For new applications, it is recommended to use the standard dataset instead of the legacy dataset.