ABB phase busbars enable safe and economical cross-wiring of circuit breakers, residual current devices and other modular installation devices. The following must be taken into account for correct phase busbar selection: terminal type (double terminal or cage terminal), number of poles of the devices (1, 2, 3, 4, 1+N or 3+N), device type (circuit breakers, residual current devices or modular installation devices), combinations of the different device types, use of circuit breakers with auxiliary switches mounted on the right and bottom, phase busbar connection cross-section (current carrying capacity), number of modules (selection of standard phase busbars or shortenable phase busbars)