The Allen-Bradley 1756-IH16I is a high-performance 16-point DC digital input module designed for the ControlLogix platform. This module provides individually isolated inputs, ensuring electrical separation between input channels to protect sensitive control circuitry from ground loops and electrical interference in industrial environments. It is engineered for high-voltage DC applications, supporting a wide operating range to maintain reliable signal acquisition.
Features
16 individually isolated input points for superior channel-to-channel protection.
Designed for 125V DC sink/source input applications.
Wide operating voltage range of 90 to 146V DC.
Programmable input delay time (6ms base plus selectable filter times) to optimize signal noise rejection.
Seamless integration with the ControlLogix backplane for high-speed data transfer.
Applications
This module is typically deployed in industrial automation systems where electrical isolation is critical, such as power distribution monitoring, heavy machinery control, and process automation where field devices operate at higher DC voltages. It is suitable for use in ControlLogix chassis-based systems requiring robust signal conditioning.
Technical Specifications
Model
1756-IH16I
Manufacturer
Allen-Bradley
Input Points
16 (Individually Isolated)
Voltage Category
125V DC Sink/Source
Operating Range
90-146V DC
Input Delay
6 ms + selectable filter
Mounting
ControlLogix Chassis
Installation Guidelines
Ensure the ControlLogix chassis is powered down before inserting or removing the 1756-IH16I module to prevent electrical arcing or damage to the backplane.
Use appropriate shielded cabling to minimize EMI/RFI interference, especially when routing high-voltage DC signals.
Verify that the module is fully seated in the chassis slot and the locking tab is engaged to ensure proper electrical contact.
Maintain adequate spacing within the cabinet to allow for proper airflow and heat dissipation.
Follow standard ESD (Electrostatic Discharge) precautions when handling the module to protect internal circuitry.
FAQ
Is the 1756-IH16I module compatible with all ControlLogix chassis? Yes, this module is designed for standard ControlLogix I/O chassis. Ensure your firmware supports the specific module revision.
What is the primary benefit of the individual isolation? Individual isolation prevents ground loops and ensures that a fault on one input channel does not propagate to other channels or the module's backplane interface.
