ABB OTDC range of DC switch-disconnectors

The ABB OTDC range of switch-disconnectors is specifically designed for direct current (DC) applications including solar photovoltaic (PV) systems - one of the most popular and technically demanding.

Switch-disconnectors are largely used as the main switch in low-voltage switchgear for distribution of power, starting and stopping motors and isolating loads during maintenance. In PV systems. They are relied on to operate continuously in hot locations, to break current and provide isolation at exceptionally high voltages.

Despite their compact size, OTDC switch-disconnectors have very high insulation voltage ratings and the DC-rated operational voltage can be scaled up to 1200 V due to a carefully optimised arc dissipation plate design and to dual magnetic breaking (DMB) action. This flexibility can be achieved because of the modular design and without increasing the footprint area.

The switch has a symmetrical power pole design, so the connections work in both ways and the switch operation is independent of the user (quick make, quick break). Since OTDC has a robust, authentic switch-disconnector design, it is not vulnerable to voltage peaks, making PV systems safe and reliable over a wide range of voltages.

OTDC has a flexible, modular design which allows the mechanism to be located at the side or between the poles, and for special applications, such as two discrete DC circuits, 4-pole versions (2 x 1000 VDC) can be built.