The Allen-Bradley 1756-OB8 is a ControlLogix discrete output module. It features eight (8) 24VDC output channels in two (2) groups of four (4) channels each. Each channel delivers an output voltage range of 10–30 volts DC with a nominal signal voltage of 24 volts DC. It is compatible for use with any ControlLogix chassis and uses the 1756-TBNH and 1756-TBSH Removable Terminal Block (RTB).