Free instrumentation calculators

Quick calculators for the math that comes up in the field and on Block and Red Seal Instrumentation & Control exams. Each one includes the formula and worked examples. No account needed.

• 4–20 mA Scaling CalculatorConvert between mA, percent of span and engineering units for any range, with NAMUR NE 43 limits.
• DP Flow Square Root CalculatorConvert differential pressure to flow (and back) for orifice, venturi and other DP flowmeters.
• DP Level Range CalculatorWork out LRV and URV for a d/p level transmitter, including zero suppression, elevation and wet legs.
• Pt100 / Pt1000 RTD CalculatorConvert RTD resistance to temperature and back using the IEC 60751 (α = 0.00385) curve.
• 4–20 mA Loop Power CalculatorCheck whether a two-wire transmitter gets enough voltage once cable and receiver resistance are counted.