Observed arrival · 2026-09-30
Controls Calculator: practical math for industrial controls
A collection of eight free, browser-based calculators for PLC, SCADA, EtherCAT, Modbus RTU, and related controls-engineering tasks.
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- Controls engineers working with PLC and OT systems
- Worth noticing
- The Modbus RTU tool models message sizes and baud-rate-dependent inter-frame timing, with device processing delay entered separately.
Field notes
The calculators expose their working assumptions instead of presenting estimates as certified results. For example, the historian tool uses a stated per-change storage estimate, while the cooling tool notes that solar gain, hot spots, and certified enclosure data are outside its model. The page also advises checking power-supply startup current, ambient derating, and manufacturer curves separately.
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