Allen-Bradley 1791-16A0 Block I/O Module with 16 120VAC Inputs

Technical Specifications Breakdown

Key parameters for the 1791-16A0 are listed below for quick reference:

Industry Applications for Distributed Input Acquisition

It is compatible with proximity switches, limit switches, selector switches, float switches, and pushbutton switches. For example, in a conveyor system, limit switches signal product presence, while float switches monitor coolant levels. The 1791-16A0 consolidates these signals into two isolated groups of eight inputs, simplifying troubleshooting and reducing panel space.

Installation and Setup Guidance

Mount the 1791-16A0 vertically or horizontally using the provided slots. Ensure adequate clearance of at least 2 inches (58.0 cm) on all sides for ventilation. Connect external power within the 85-132VAC range at 47-63 Hz. Wire field devices to the input terminals, respecting the on-state voltage range of 79-132VAC. The module supports daisy-chain configuration to a scanner on the network, typically a controller. Verify that the off-state leakage current of any connected output module (e.g., 1771 series) is less than the minimum off-state current of 2.3mA.

Maintenance and Reliability

Periodically inspect the module for dust accumulation and ensure airflow clearance remains unobstructed. The maximum surge current rating of 10A for 50ms (repeatable every 2 seconds) provides robustness against transient loads. Operate within the specified voltage and frequency limits to maintain long-term reliability. No internal adjustments are required.

Problem-Solution Framework for Reliable Input Acquisition

Industrial facilities often struggle with consolidating discrete sensor signals from multiple field devices into a programmable logic controller. The Allen-Bradley 1791-16A0 Block I/O module directly addresses this challenge by embedding 16 input channels, power supply, and PLC interface into a single, self-contained unit. This eliminates the need for separate racks and adapters, reducing wiring complexity and installation costs.

Compatibility and Integration

The minimum on-state voltage of the Block I/O must exceed the supply voltage minus the on-state voltage drop across the 1771 output module. Compatible modules include the 1771-OAN, 1771-OD16, 1771-ODD, and 1771-ODZ. This interoperability allows flexible system expansion without redesign.

Selection Guide and Purchasing Advice

When selecting a Block I/O module, consider the number of inputs required and the voltage compatibility of your field devices. The 1791-16A0 offers 16 120VAC inputs in a compact form factor. AutoDCSTech stocks this module and can assist with lifecycle status verification. Please verify current availability before ordering.

Please verify current lifecycle status and availability with AutoDCSTech before ordering.