R Series Circuit Breakers Altech R Series Circuit Breakers are DIN-rail mounted and feature 17.5mm width per pole, 0.5 to 63A rated current range, and 10kA short-circuit withstand capacity. These thermal magnetic supplementary protectors are UL 1077 recognized and include 1-, 2-, and 3-pole variants. Altech R Series Circuit Breakers feature a positive trip indicator with green for 'off/tripped' and red for 'on' status. The R series is ideal for sensitive electronics, power supplies, and appliance circuits.