Standard units are available with operating voltages from 5KV to 190KV AC PK or DC, with peak test voltage to 300KV PK, continuous currents to 1,200 amps and interrupt currents to 28,000 amps. Capacitor discharge closing currents up to 100,000 amps are possible depending on time constant of discharge down to 37% level.

With repeated high speed DC interruptions or crobar type operations in DC circuits, both transformers and loads must be protected from possible transient overvoltages and inrush currents. Transformers must be well braced and end turns especially well insulated. Loads, especially inductive loads, must have capacitance and/or non-linear resistance in parallel at their terminals and on the output terminals of the transformer. Capacitors with at least 1.5 times voltage rating (in the order of .01 to 0.25 mfd) in series with 1 to 2 ohms per KV, are recommended. GE Thyrite or similar nonlinear resistance carefully rated for appropriate operating current is also helpful. To limit inrush on re-energizing after a crobar has tripped a primary breaker, a dual step-start contactor or circuit breaker is recommended. See Three Pole HV Vacuum Contactors / Circuit Breakers for further power control information.

Two auxiliary SPDT contacts are standard on each model. Additional auxiliary contacts can be ordered.