Free Engineering Tools
Free Electrical Testing Calculators
Small, fast tools for the people who use our instruments, from the team that has been building them in Howrah since 1963. No sign-up, nothing to install.
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Insulation testing
IR Temperature Correction
Correct a megger reading to 20°C or 40°C so readings from different days can be compared.
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Insulation testing
PI and DAR Calculator
Turn 30 s, 1 min and 10 min readings into Polarization Index and DAR with a verdict.
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Insulation testing
Motor Minimum IR Check
Check a winding reading against the IEEE 43 recommended minimum, corrected to 40°C.
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Insulation testing
Insulation Test Voltage Selector
Pick the right megger test voltage for a motor winding (IEEE 43) or a low-voltage installation (IEC 60364-6).
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Power and motors
Three-Phase Power and Current
Convert between kW, kVA, kVAR and line current for any three-phase or single-phase load.
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Power and motors
Power Factor Correction
Find the capacitor kVAR needed to lift your power factor to a target, with the kVA released.
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Power and motors
Motor Speed and Slip
Synchronous speed from poles and frequency, plus slip and rotor frequency from a measured speed.
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Cables and circuits
Cable Voltage Drop
Estimate the voltage drop of a copper or aluminium cable run, corrected for conductor temperature.
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Cables and circuits
Ohm's Law and Power
Enter any two of voltage, current, resistance or power and get the other two instantly.
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Measurement
Meter Accuracy and Error Band
Turn a "±(% of reading + digits)" spec into the real error band around your displayed value.
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Measurement
Electrical Unit Converter
Convert SI prefixes, power (kW, HP, BTU/h, TR), temperature, decibels (dBm, dBV) and wire gauge (AWG to mm2).
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Measurement
Resistor Colour Code
Click the colour bands on a drawn resistor to read its value, tolerance and range. 4, 5 and 6 bands.
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Earthing and soil
Soil Resistivity (Wenner)
Turn four-pin Wenner readings into soil resistivity at each depth, with the average and a trend verdict.
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Earthing and soil
Earth Rod Resistance
Estimate the resistance of a driven earth rod from soil resistivity, length and diameter, and how many rods you need.
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Scopes and signals
Scope Bandwidth and Rise Time
Check whether a scope is fast enough for your signal: rise time, amplitude error and the bandwidth you should buy.
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Scopes and signals
Scope Screen Reading
Convert divisions on the screen into period, frequency, peak-to-peak, peak and RMS voltage.
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