Circuit breakers are ubiquitous wherever there are electrical circuits that need protection against excess current caused by an overload or short circuit. They range in size and capacity from devices the size of a fingernail used for semiconductor protection to devices as large as a truck designed to protect the high voltage circuits that supply power to cities.
Grid testing solutions must contend with difficult electromagnetic and environmental conditions, providing clean and reliable measurement results to ensure a reliable supply of power from production through to consumers. Electrical power is—in most cases—not produced where it is consumed. The power grid covers the infrastructure connecting plants with end users, ultimately transporting electrical energy from where it is produced to where it is used.
The power grid is organized into different voltage levels from a few hundred volts (LV), to several 10 kV (MV) up to several 100 kV (HV), depending on the amount of power transportation capacity needed. Thus grid testing products must be capable of handling starkly different voltage levels.
The different voltage levels are interconnected by substations which contain voltage transformers, circuit breakers, surge arrestors, isolators etc. as well as other measurement equipment and switchgear.