Model Explanation

B873 = 4-channel analog input general series; 001 = Fixed dual-range specification, single-channel hardware is optional for 4-20mA current / 1-5VDC voltage input. There are no other range jumper options, and it differs from other multi-range models of B873. Technical Specifications

Channel: 4 independent isolation channels, with a withstand voltage of 250VAC between channels and 300VAC between channels and the backplane for isolation protection.

Input range: Select one from 4-20mA or 1-5VDC, with single-channel jumper for switching.

Input impedance: 1MΩ for voltage mode, 250Ω for current mode, standard sampling resistor.

Digital-to-analog accuracy: 12-bit resolution, full-scale error ≤ ±0.05% FS, single-point error ≤ 7mV

Backplane power consumption: 5VDC/300mA, 4.3V/300mA, no external power supply

Scanning rate: 4-channel full-channel single-shot acquisition 400ms

Dimensions: 51 (W) × 203 (H) × 279 (D) mm, net weight approximately 0.72kg

Status indicator lights: ACT running green light, OVER RANGE over-range red light, UNDER RANGE under-range red light

Operating conditions: 0-60℃ operation, storage -40-85℃, humidity < 80% RH, no condensation

Interface and matching base

Matching screw terminal base: AS-8535-000, two-wire system transmitter wiring, current type connected to 4-20mA loop, voltage type connected to 1-5V instrument. Core function

Convert the 4-20mA/1-5V analog signals from the on-site temperature, pressure and liquid level transmitters into digital quantities within the PLC, thereby achieving the collection of process parameters and the alarm for range over-limit. Applicable scenarios

The old Modicon 984 PLCs in thermal power, petrochemical and water treatment industries are being replaced through technical upgrades. The centralized collection points for conventional two-wire transmitters are being utilized.

Operation and Maintenance

The modules can be directly plugged and installed into the I/O slots of the 800 rack. The jumpers inside the board can be changed to alter the current/voltage format of a single channel; OVER is lit = input exceeds the upper limit, UNDER is lit = input is below the lower limit; The entire series is compatible and can be used in mixed mode with all models of B872 AO cards on the same rack.