Using its in-house software engineering expertise, Cressall Resistors has developed an iPhone app for solving Ohm’s Law.

Ohm’s Law is the essential mathematical model that engineers use for mentally mapping out electrical circuits. The brainchild of Peter Duncan, who retired as managing director of Cressall Resistors at the end of 2012, the iPhone app originated as a routine for solving Ohm’s Law on his handheld Hewlett Packard programmable scientific calculator. Duncan was using it daily and thought it would be useful to other electrical engineers as it allows them to input any two of the key variables of volts, amps, ohms and power, and calculates the other two.

Once the first calculation is solved, an engineer can then change the value of any of the resulting variables, and the app will back-solve all the other variables automatically.

Chris Johnson of Cressall Resistors,said: “With our app you can change any parameter value and keep playing around with it until you come to a satisfactory solution. If you’re in any doubt about what you’re doing, you can call up a power triangle diagram.

“The Android version is in development now and being ported over. We will extend the language options available too, in partnership with our international agents who have volunteered to give us translations for their home markets. We are expecting to launch German, French and Swedish versions soon.”

The app has already been downloaded more than a thousand times in less than a month.

Johnson reveals that the next release on the drawing board for the app is a star-delta calculator for three-phase electric motors, with more ideas over the horizon.