Electrical Calculations
Measurements & Test Calculations
Scale instrumentation signals, calculate transformer ratios, and check current-loop burden.
Not sure where to start? Choose by task and required inputs.
Current Transformer Ratio CalculatorConvert measured CT secondary current to estimated primary current using entered nameplate ratings.Instrument Transformer Meter Multiplier CalculatorCombine CT and PT ratios and adjust a register value for an existing meter multiplier.4–20 mA Signal Scaling CalculatorConvert loop current to an engineering value or calculate current from a configured range.Current Loop Load Resistance CalculatorEstimate the remaining allowable loop resistance from supply voltage and entered device voltage drops.
Which tool fits your task?
Decide whether you are converting an instrument ratio, applying a meter multiplier, scaling a process signal or checking the available loop voltage. These inputs are not interchangeable.
| Your task | Inputs to collect | Tool and scope |
|---|---|---|
| Convert CT secondary current to primary current | CT nameplate ratio and measured secondary current. | Current Transformer Ratio Calculator The arithmetic does not verify polarity, installation or instrument accuracy. |
| Apply CT/PT ratios to a meter register | Ratios and any multiplier already applied by the register. | Instrument Transformer Meter Multiplier Calculator Check the meter configuration to avoid applying the same ratio twice. |
| Convert a linear 4–20 mA signal and engineering value | Configured current endpoints and engineering-range endpoints. | 4–20 mA Signal Scaling Calculator A scaled reading does not diagnose a wiring fault or non-linear transmitter setup. |
| Check available loop voltage and additional resistance | Supply, transmitter minimum voltage, input burden and other drops. | Current Loop Load Resistance Calculator Use the documented device data and maximum loop current. |