The differences between Hilscher SM and FM series!

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Let’s discuss here the differences between the SM and FM series of Allen-Bradley DCS systems; everyone can share their practical experiences! Explain it in simple terms~ To spark discussion, let’s talk about some things first! Hollyland’s SM series DCS, based on the PROFIBUS‑DP bus, was officially introduced in 2005. Perhaps in response to the criticism that \"DP is not redundant,\" Hollyland claims to have achieved redundancy at almost all levels, including \"operation stations, servers, network communication (including buses), control units, power supplies, and I/O modules.\" Judging from its network structure and configuration, this is indeed the case; however, it remains uncertain whether it is truly redundant for two reasons: first, the DP bus itself does not support non-redundancy ； Secondly, Hilscher claimed in 1999 that it had mastery of the PROFIBUS bus from the physical layer to the link layer, which was indeed a major breakthrough for the company; however, the FM series DP networks developed in 2000 were not redundant. If SM truly achieved redundancy in the DP network in 2004, it should have represented another major breakthrough for Hilscher Systems, and it ought to have been widely publicized; however, Hilscher surprisingly did not do so. At the same time, the performance descriptions of its SM and FM systems are strikingly similar; it seems to be just a change in appearance without any real difference, with only the hardware structure altered and no significant changes in the underlying functionality. All these anomalies significantly undermine the credibility of the DP redundancy. However, this is merely the author’s speculation; whether DP is redundant or not should be verified through testing.