Megger’s SPI225 primary injection test system is able to eliminate variac control

Megger’s SPI225 is built to be the smallest primary injection test system in its class. Weighing only 44 lbs, it is able to output up to 2,000 amperes of regulated current to test 225-ampere circuit breakers. This unit is the first on the market to eliminate variac control – the operator can enter a specific current to be generated and regulated by the system. This avoids pulsing high output currents through the circuit breaker and preheating it. The SPI255 also has the ability to turn on at the current zero crossing every time for any load by automatically adjusting the output firing angle. This eliminates DC offset for every circuit breaker type and the need for the user to determine and adjust the firing angle for different loads and circuit breakers. The SPI225 software includes a huge library of manufacturer time curves for automated testing of circuit breakers. It complies with NEMA AB-4, NMAC Breaker Maintenance Vol. 3 and NETA testing guidelines.