1771-IFMS Allen-Bradley Intrinsically Safe Millivolt Input Module

Allen-Bradley 1771-IFMS Intrinsically Safe Fast Millivolt Input Module for PLC5

Key Technical Specifications

• Brand & Model: Allen-Bradley 1771-IFMS intrinsically safe fast millivolt input module.
• Input Channels: 8 differential inputs through intrinsically safe connection.
• Input Voltage Range: 0-50 mV DC (low-level millivolt signals).
• Resolution & Accuracy: 12-bit binary; accuracy 0.1% of range @ 25°C.
• Linearity & Repeatability: ±1 LSB linearity, ±1 LSB repeatability.
• A/D Converter: Monotonic output with no missing codes.
• Update Time: 14.5 ms for all 8 differential channels (without digital filtering).
• Data Format: ±32,767 binary or ±9999 BCD scaling.
• Input Impedance: 1 Megaohm.
• Common-Mode Rejection: 100 dB at 60 Hz.
• Input Overvoltage Protection: 32V DC (maximum input ±10V DC operating range).
• Backplane Current: 750 mA @ 5V DC (no external power required).
• Protective Coating: Conformal coating protects against moisture and contaminants.
• Signal Delays (typical): DC Off 20 ms (±9 ms); AC Off 24 ms (±10 ms).
• Wiring Arm: Includes 1771-WG field wiring arm.
• Temperature & Humidity: Operating 0 to 60°C; humidity 5-95% non-condensing.
• Shock Rating: Operating 15G, non-operating 30G.

Installation & Wiring Guidelines

• Mounts in any 1771 I/O chassis and occupies a single slot (rack mountable).
• Use the included 1771-WG wiring arm for all field connections; torque screws to 0.8-1.0 Nm (7-9 lb-in).
• Acceptable wire size: 0.25-2.5 mm² (22-14 AWG) solid or stranded copper with 75°C insulation rating.
• Keying bands: install between pins 10-12 (lower) and 24-26 (upper) for correct module insertion.
• Important: The 1771-IFMS does not support removal or insertion under power (RIUP). Always power down the PLC5 system before installation or removal.
• Follow electrostatic discharge (ESD) precautions when handling the module.
• Equipment connected to the non-intrinsically safe side must not generate voltages exceeding 250V RMS.

Intrinsically Safe & Environmental Features

• Designed for hazardous locations with intrinsic safety barriers on field wiring.
• Conformal coating provides additional protection against moisture and corrosion.
• Monotonic A/D converter ensures no missing codes for reliable low-level signal conversion.
• High common-mode rejection (100 dB at 60 Hz) minimizes interference in industrial environments.
• Complies with T6 North American temperature code for hazardous area installations.
• Input overvoltage protection up to 32V safeguards the module against wiring faults.

Package Contents

• Allen‑Bradley 1771-IFMS intrinsically safe fast millivolt input module (1 unit).
• 1771-WG wiring arm (attached or included separately).
• Quick reference documentation leaflet.
• Anti‑static protective packaging.

Frequently Asked Questions (FAQ)

• What does "intrinsically safe" mean for the 1771-IFMS? The module connects to field devices through intrinsic safety barriers, limiting energy in hazardous areas. This prevents ignition in explosive atmospheres while allowing normal signal measurement.
• What types of sensors work with the 1771-IFMS? It accepts low-level millivolt signals from thermocouples, strain gauges, pressure transducers, and other sensors with 0-50 mV output.
• Why choose the 1771-IFMS over standard analog modules? Its 0-50 mV range, 14.5 ms fast update, and intrinsic safety certification make it the only choice for hazardous locations requiring precise low-voltage measurement.
• Can I install or remove this module while the system is powered? No, the 1771-IFMS does not support RIUP. You must power down the PLC5 chassis before installation or removal to prevent damage.
• What wire size and torque should I use for the 1771-WG wiring arm? Use 22-14 AWG copper wire with 75°C insulation. Tighten screws to 0.8-1.0 Nm (7-9 lb-in) for reliable connections.
• What is the update time for all eight channels? The module scans all eight differential inputs in 14.5 ms without digital filtering, providing fast response for critical millivolt signals.
• Does the module provide overvoltage protection? Yes, it includes input overvoltage protection up to 32V, though the normal operating range is ±10V DC maximum.
• What is your typical shipping time for the 1771-IFMS? We stock this item as new original surplus. We ship within 5 days after order confirmation via FedEx, UPS, or DHL.
• Can I return the module if it doesn't meet my needs? Yes, we accept returns within 30 days. The module must be in new, unused condition with its original packaging.

Contact Information Inquiries: sales@nex-auto.com | +86 153 9242 9628

Partner: NexAuto Technology Limited