1771-ID16 – Digital AC/DC Input Module (PLC-5, 16 Inputs)

Oiltech Controls’s Insight

The 1771-ID16 from Allen‑Bradley / Rockwell Automation is a workhorse 120V AC/DC isolated input module for the PLC‑5 platform. It delivers 16 universal inputs that accept both AC (77‑138V) and DC (105‑138V) signals. The module features selectable input filtering that suppresses transients from contact bounce or electrical noise – improving power quality and reducing downtime. With a factory filter time of 9 ms, it offers typical on‑delay of 1 ms and off‑delay of 9 or 18 ms (AC) / 9 ms (DC). The 1771‑WN wiring arm (included) attaches to the chassis pivot bar, so you can remove or insert the module without disconnecting field wires – a huge plus for maintenance. This module excels in isolated‑circuit multi‑phase applications with float switches, selector switches, limit switches, and pushbuttons.

Key Technical Specifications

• Brand / Manufacturer: Allen‑Bradley / Rockwell Automation
• Part Number: 1771-ID16
• Series: PLC‑5
• Module Type: Digital AC/DC Input
• Number of Inputs: 16 (isolated)
• Voltage Category: 120V AC/DC
• AC Operating Voltage: 77…138V AC
• DC Operating Voltage: 105…138V DC
• Backplane Current: 75 mA
• Max AC Off‑State Current: 4.0 mA
• Max DC Off‑State Current: 1.8 mA
• Typical AC On‑Delay: 1 ms
• Typical DC On‑Delay: 1 ms
• Typical AC Off‑Delay: 9 or 18 ms (selectable)
• Typical DC Off‑Delay: 9 ms
• Wiring Arm: 1771‑WN (included)
• Dimensions: 89 × 165 × 51 mm (3.5 × 6.5 × 2.0 in)

Signal Filtering & Performance Details

• Filter time: Factory set at 9 ms (user‑selectable).
• On‑to‑off delay (AC): 9 or 18 ms – suppresses contact bounce.
• On‑to‑off delay (DC): 9 ms – clean transition for DC signals.
• Off‑to‑on delay (both AC/DC): 1 ms – fast response for critical inputs.
• Capacitive input impedance: Causes a small initial inrush current – normal behavior.
• Noise immunity: Filtering reduces radiated electrical noise effects.

Compatible Chassis & Wiring

• Compatible with: 1771‑A1B, 1771‑A4B, or later I/O chassis.
• Wiring arm: 1771‑WN (40‑terminal field arm included).
• Hot‑swap capability: Remove/insert module without disconnecting wires – arm stays on pivot bar.
• Terminals: Accepts solid or stranded copper wire (14‑22 AWG).

Installation & Mounting Guide

• Mounting: Insert into any slot of a 1771 I/O chassis.
• Wiring arm attachment: Snap the 1771‑WN arm onto the chassis pivot bar.
• Field wiring: Connect AC/DC field devices to the 40 terminals.
• Grounding: Use chassis ground for noise reduction.
• Orientation: Vertical or horizontal – no derating required.

Maintenance & Diagnostic Features

• LED indicators: Each input has a status LED (on/off).
• Module self‑test: Power‑up diagnostics check internal circuits.
• Filter adjustment: Selectable via configuration (software or DIP switch).
• Fault reporting: The processor reads input states; no separate fault codes.
• Cleaning: Use dry cloth – avoid solvents that may damage the plastic housing.

Typical Devices & Applications

• Suitable for: Float switches, selector switches, limit switches, pushbuttons.
• Applications: Isolated‑circuit multi‑phase systems, pump control, conveyor interlocks, safety circuits.
• Industry: Factory automation, material handling, packaging, water/wastewater.
• Mixed voltage environments: Handles both AC and DC sensors in one module.

5 Professional FAQ (Experience & Selection Guide)

• Q: Can I mix AC and DC inputs on the same module?
  A: Yes – each input accepts either AC (77‑138V) or DC (105‑138V) independently. This is a key advantage for mixed-voltage panels.
• Q: How do I choose between 9 ms and 18 ms off‑delay for AC?
  A: Use 9 ms for fast‑acting signals (e.g., emergency stops). Use 18 ms for noisy environments with contact bounce (e.g., mechanical limit switches) – it provides better noise rejection.
• Q: What happens if I apply DC voltage higher than 138V?
  A: Exceeding 138V DC may damage the input circuit. Always verify your sensor output before wiring.
• Q: Can I hot‑swap the 1771‑ID16 while the chassis is powered?
  A: Yes – the 1771‑WN wiring arm stays on the pivot bar, so you can remove/replace the module without disconnecting wires. This minimizes downtime.
• Q: Is this module compatible with 1771‑A1B and A4B chassis only?
  A: It works with any 1771‑A1B, ‑A4B, or later series chassis. Older 1771‑A1 chassis may require an adapter – check your hardware revision.

Package, Warranty & Shipping

• 1 × 1771‑ID16 module
• 1 × 1771‑WN 40‑terminal wiring arm (included)
• 1 × Installation guide (printed)
• Warranty: 12 months against manufacturing defects.
• Shipping: FedEx, UPS, or DHL – 24‑28 hours dispatch after order.

Why Buy From Oiltech Controls?

• 15+ years in industrial automation spares – we know legacy PLCs.
• Global shipping via FedEx, UPS, DHL – fast and tracked.
• Tested industrial surplus / refurbished modules – ready to run.
• 12‑month warranty – peace of mind for obsolete parts.
• Technical verification before shipment – no DOA.
• Support for obsolete control systems – we keep your plant running.

Contact: info@oiltechcontrols.com  |  +86 158 8020 0923 (WhatsApp)

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