A battery impedance test is a way of predicting future battery failure. An electrical current is passed through each battery in turn and a measurement taken. The internal impedance of each battery is then calculated, logged in a table and plotted on a graph.
Over a battery’s life, its internal impedance rises until it reaches a level defined by the battery manufacturer as being critical for that battery type. The individual battery, or set of batteries, should then be replaced. By comparing the internal impedance values with the others, and with those obtained at the last site visit, those batteries with rising impedance values can be identified and replaced before complete failure occurs.
A report will be provided after the batteries have been tested, to report on the status of the batteries, advising which, if any, will need to be replaced.