This is part of an ongoing series building a real enterprise-grade pump station control system in Siemens TIA Portal, and it tackles two function blocks that show up in almost every industrial PLC project: a mode manager (Auto/Manual/Off state handling with interlocks) and an analog scaling block (converting raw 0–27648 integer values from analog input cards into engineering units like PSI, GPM, or meters).

What makes this worth watching is that it's written in Structured Control Language (SCL) rather than ladder logic. SCL is closer to Pascal and is where serious Siemens developers spend their time for anything reusable, but most YouTube PLC tutorials stick to ladder because it photographs better. Seeing FB design with proper InOut parameters, instance data, and reusable scaling math is genuinely educational for anyone moving past beginner ladder examples.

The mode manager pattern in particular — handling operator commands, hardwired selector switches, fault states, and remote SCADA overrides without creating race conditions — is the kind of thing you only learn from someone who has commissioned real plants. The series format means the FBs are being built to actually integrate with pumps, VFDs, and HMI faceplates later.