The Schneider Electric AS-B875-111 is a versatile analog input module belonging to the Modicon 800 series. Designed for demanding industrial automation applications, it provides high-precision analog-to-digital (A/D) conversion. The module features flexible, user-selectable channel configurations, supporting either 8 differential or 16 single-ended inputs, making it an ideal choice for complex process control and monitoring systems.

Product Technical Specifications

• Part Number: AS-B875-111
• Product Series: Modicon 800 Series
• Channel Capacity: 8 (differential) or 16 (single-ended), user-selectable
• Resolution: 14-bit
• Accuracy: ±0.1%
• Linearity: ±0.05%
• Update Time: 10 ms (8-channel mode) / 20 ms (16-channel mode)
• Operating Temperature: Standard industrial range
• Weight: ~0.91 kg (2.0 lbs)
• 原产地 (Country of Origin): United States / Global

 

Mechanical Installation Requirements

• Mounting Method: Designed for backplane mounting within a standard 800 series I/O chassis. Ensure the module is fully seated and the mechanical latch is securely engaged.
• Clearance: Maintain a minimum vertical clearance of 50mm above and below the module to facilitate cable routing and ensure adequate convective airflow.
• Thermal Management: Keep at least 20mm of lateral space between this module and other high-heat-generating devices to maintain optimal thermal stability.

 

Electrical Wiring & Grounding

• Terminal Connectivity: Requires the AS-8535-000 screw terminal block for field wiring. Refer to the device pin-out diagram for correct signal assignment.
• Wire Gauge: Use shielded twisted-pair cabling with a cross-section of 0.5mm² to 1.5mm² (20–16 AWG) to ensure signal integrity and electromagnetic compatibility (EMC).
• Grounding Norms: The module provides 1500 VAC channel-to-module isolation. Connect the chassis ground lug directly to the main cabinet protective earth (PE) bus using a low-impedance copper strap to minimize signal noise and interference.

 

Input Configuration & Settings

• Voltage Modes: Supports 0–5V, 1–5V, -5V to +5V, 0–10V, and -10V to +10V.
• Current Modes: Supports 0–20mA, 4–20mA, and -20mA to +20mA.
• Configuration: Input ranges and modes are configured via onboard DIP switches. Refer to the 800 series reference manual for specific switch position tables for bipolar vs. unipolar operation.

 

Frequently Asked Questions (Q&A)

Q: How do I switch between 8-channel and 16-channel modes? A: The channel mode is user-selectable through the module’s configuration switches. Please consult the product documentation for the specific switch logic.

Q: What is the primary difference between AS-B875-111 and AS-B877-111? A: The AS-B875-111 is designed for differential input capability, whereas the AS-B877-111 is typically designated for 16-channel single-ended applications.

Q: Does this module require an external power supply? A: No, it draws its required operating power directly from the 800 series backplane (typically +5V and +4.3V rails).

Q: What is the significance of the “14-bit” resolution? A: A 14-bit resolution provides high granularity, allowing the module to divide the analog signal into 16,384 discrete levels, which ensures superior accuracy in fine-tuned control loops.