1756-OH8I

The 1756-OH8I ControlLogix DC Digital Output Module by Allen-Bradley is a digital output module with 8 isolated 120V DC sinking/sourcing outputs located on the chassis of the ControlLogix devices. It has a voltage range of 90-146V DC and a maximum output signal delay time of 2ms for both ON to OFF and OFF to ON. The 1756-OH8I has a back-plane draw current of 2mA at 24V and 210mA at 5.1V with an overall backplane power of 1.1W. It dissipates 3.3W (11.25 BTU/hr) of heat at 60 °C (140 °F) when operational and it has an OFF-state leakage current of 1mA per point. In ON-state, the 1756-OH8I has a drop voltage of 2V DC at 2A and the maximum current retained on each output point is 2A. The minimum current load on each point is 2mA and with a surge of 4A on each point, the maximum current the 1756-OH8I module can sustain is 8A at 60 °C (140 °F). The isolation voltage between its outputs-to-backplane and output-to-output is 250V with the basic insulation type tested at 1350V AC for 2s. The 1756-OH8I has a factory-designated T4A North America temperature code and it comes with an open-style enclosure. It has a 0-60 °C (32-140 °F) operating temperature range at 5-95% relative humidity environment. The 1756-OH8I is designed to sustain an operational vibration of 2G at 10-500Hz and a shock rating of up to 20G.