| SEL-3573 Station PDC | SEL-3555 Real-Time Automation Controller (RTAC) | |
| Number of Inputs | 120 | 100 |
| Number of Outputs | 10 | 100 |
| Archiving | Yes | Yes (with DDR extension) |
| Data Rates | Up to 240 messages per second | Up to 240 messages per second |
| Control | No | Yes |
| Input Format | IEEE C37.118 | IEEE C37.118 DNP3 Modbus SEL Fast Message |
| Output Format | IEEE C37.118 | IEEE C37.118 DNP3 Modbus SEL Mirrored Bits communications SEL Fast Message |
| Platform | Hardware | Hardware |
| Selectable Outputs | Yes | Yes |
| Multiple Input Rates | Yes | No |