Allen-Bradley 1756-IA16 Isolated Analog Input Module

The Allen-Bradley 1756-IA16 is a 16-point isolated digital input module for ControlLogix backplanes, delivering two independently isolated banks of eight inputs to help prevent cross-talk and ground-loop issues between circuits. It accepts 74–132 V AC signals (47–63 Hz) with a nominal 120 V AC rating, and provides 125 V continuous isolation between inputs and the backplane as well as between the two input groups (with no isolation between individual inputs within a group). Termination is via removable blocks (1756-TBNH or 1756-TBSH), and the module supports debounced, timestamped sensing with configurable timing—off-to-on delays up to 10 ms with a 1–2 ms filter and on-to-off delays up to 8 ms with a 9–18 ms filter—plus input timestamps within ±200 µs and a cyclic update time of 200 µs to 750 ms. Electrical and thermal data include a backplane Power draw of 0.58 W and a maximum dissipation of 5.8 W at 60 °C, an input impedance of about 10.15 kΩ at 132 V AC, and operating currents of 5–13 mA when active with up to 2.5 mA in the off state. The card fits a 1-inch slot width, supports electronic module keying, and uses standard Rockwell RTBs in open-style enclosures, with North American temperature rating of T4.