Product Description

The Allen-Bradley 1756-IV16 is a high-performance Digital Sourcing I/O Module designed exclusively for the Rockwell Automation ControlLogix platform. As a critical component in modern industrial automation, this 1756-IV16 module provides 16 discrete input points, organized into 2 isolated groups of 8 points each, enabling efficient field device monitoring in demanding manufacturing environments. Engineered for DC sourcing applications, the Allen-Bradley 1756-IV16 accepts a wide operating voltage range of 10 to 30 Volts DC (nominal 24V DC), making it versatile for global industrial installations.

Technical Specifications & Core Parameters

• Inputs Quantity: 16 (non-isolated between groups, 8 points per group)

• Operating Voltage Range: 10 – 30 Volts DC (12-24V DC source category)

• Nominal Input Voltage: 24 Volts DC

• Maximum Input Impedance: 3.2 kΩ at 30 Volts DC

• Off-State Maximum Voltage/Current: 5 Volts DC / 1.5 mA

• On-State Current Range: 2 mA (min. at 10V) to 10 mA (max. at 30V)

• Total Backplane Power: 0.61 Watts

• Maximum Power Dissipation: 5.1 Watts at 60°C (Thermal Dissipation: 18.47 BTU/hour)

• Continuous Isolation Voltage: 250 Volts (tested for safety isolation)

• Backplane Current Draw: 110 mA at 5V DC; 2 mA at 24V DC

• Maximum Inrush Current: 250 mA

Input Delay & Filtering Precision

The 1756-IV16 offers flexible user-selectable filter times to balance noise immunity and response speed. The total input delay equals hardware delay plus the selected filter time:

• Off → On Transition:

  • Hardware Delay: 280 µs (nominal) / 1 ms (maximum)

  • Selectable Filter: 0 ms, 1 ms, or 2 ms

• On → Off Transition:

  • Hardware Delay: 540 µs (nominal) / 2 ms (maximum)

  • Selectable Filter: 1 ms, 2 ms, 9 ms, or 18 ms

This dual-stage delay structure allows the Allen-Bradley 1756-IV16 to effectively debounce switch contacts and reject high-frequency electrical noise, ensuring stable and reliable data acquisition in electrically harsh environments.

Environmental Tolerance & Immunity

• Temperature Range: Operates reliably from 0°C to 60°C (horizontal mounting); derating applies for vertical mounting.

• Relative Humidity: 5% to 95% non-condensing

• Shock & Vibration: Withstands 30g operational shock and 2g @ 10-500Hz vibration, per IEC 60068-2-6.

• Noise Immunity: Built-in EMI/RFI suppression and optical isolation (250V continuous) provide superior resistance to common-mode and transient disturbances commonly found in motor control centers and high-power drive cabinets.

Installation Guidelines

The 1756-IV16 mounts directly into any slot of a ControlLogix 1756 chassis. Before insertion, you must attach a Removable Terminal Block (RTB) to the module face. Compatible RTBs include:

• 1756-TBSH (screw-clamp RTB)

• 1756-TBNH (spring-clamp RTB)

Installation Steps:

1. Ensure chassis power is OFF.

2. Attach the RTB to the front of the 1756-IV16 and secure it with the captive screws.

3. Insert the module into the selected chassis slot until the locking tab clicks.

4. Connect field wiring (solid or stranded copper, 22-14 AWG) to the RTB terminals per the wiring diagram.

5. Apply power and verify the module LED status.

What’s in the Box (Package Contents)

• 1 x Allen-Bradley 1756-IV16 module (main unit)

• 1 x RTB mounting screw kit (for securing RTB to module)

• 1 x Product information sheet (quick start guide with wiring pinout)

• Anti-static protective packaging

Note: Removable Terminal Block (1756-TBSH or 1756-TBNH) and chassis are sold separately.

Frequently Asked Questions (FAQ)

Q1: Can the 1756-IV16 be used with 5V DC sensors?
A: No. The 1756-IV16 requires a minimum of 10V DC for on-state recognition (2 mA). It is not compatible with 5V logic-level devices. Use it only with 12-24V DC sourcing sensors or dry contacts with an external power supply.

Q2: What is the difference between the 1756-IV16 and the 1756-IB16?
A: The 1756-IV16 is a sourcing input module (current flows into the module from the field device), while the 1756-IB16 is a sinking module (current flows out to the field device). They are not interchangeable. Always verify your sensor wiring type before selecting the 1756-IV16.

Q3: How do I select the appropriate filter time for my application?
A: For clean, fast signals (e.g., proximity sensors), use 0 or 1 ms filter. For mechanical switches or pushbuttons in noisy areas, select 9 or 18 ms to avoid false triggers. The 1756-IV16 allows per-group configuration via your Logix Designer project.