PLC / DCS — Process control

PID loops

• SP, PV and OP live with trends, and 24-hour loop health: time in automatic, average deviation and output saturation.
• Manual, automatic and cascade changes are submitted as change requests and go through the 8-step approval flow; cascade is offered only where a primary loop is configured.
• Tuning records (method, gains before and after, overshoot, settling time and reason) are audited.

ISA-88 batch records

• Recipes (version, phases, critical process parameters and limits) can be used only after another manager approves them.
• Batch start, each phase completion and release are signed (with platform e-signatures on GMP sites). Actual parameters are taken from history during each phase; out-of-limit CPPs are flagged as deviations.
• The person who ran a batch cannot release it; a release with deviations needs a written conclusion. Every batch record is hashed.

Controller redundancy

• Primary and standby state, synchronization, scan time and CPU load of hot-standby controller pairs.
• Alarms on loss of redundancy (only one controller, not synchronized, no primary, two primaries); switchovers are recorded automatically.

PLC protocols

• EtherNet/IP: numeric setpoint tags on Logix PLCs (BOOL, SINT, INT, DINT, REAL) can be made writable with approval, followed by a read-back check.
• Siemens S7 (read-only): STEP 7 addresses such as DB10.DBD4, DB10.DBX0.0, MW10 and IW64, batched to the negotiated PDU size.

Soft PLC and control programs

• Write programs in the browser in Structured Text, ladder, function block diagram or sequential function chart, and simulate them.
• Signed programs are deployed to the gateway. If a program fails, its outputs are handed back to the equipment.
• An optional native runtime in Rust gives bit-for-bit the same results as the Go and browser runtimes.

Industries

• New-energy manufacturing
• Biopharma & life sciences
• General & discrete manufacturing
• Copper tube & metal processing
• Glass manufacturing

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