Model Explanation

B875 = 8-channel basic analog input series; 111 = Third-generation high-end PCB, supports 8 differential / 16 single-ended switching, full voltage current range selectable, onboard configurable 250Ω sampling resistor

100: Older single-ended, general-purpose potentiometer range

101: Older single-ended fixed at 4-20mA

102: Older single-ended fixed voltage

111: New high-end model, differential / single-ended free switching, full range programmable selection Technical Specifications

Channel Configuration: Binary selection via dip switch. 8 differential inputs or 16 single-ended inputs. 250VAC isolation between channels, 300VAC withstand isolation on the backplane.

Optional input range

Voltage: 0~5V, 1~5V, ±5V, 0~10V, ±10VDC

Current: 0~20mA, 4~20mA, ±20mADC. Onboard selectable 250Ω sampling resistor

AD Conversion: 12Bit high-precision analog-to-digital conversion. Full-scale range at 25℃ ≤ ±0.10% FS

Scan Rate: Full-channel refresh, differential mode 20ms, single-ended mode 10ms

Backplane Power Supply: Rack 5VDC power supply, rated 420mA, no external on-site power required

Dimensions: 51 (W) × 203 (H) × 280 (D) mm, net weight 0.92kg

Status Indicators: RUN green light for operation, OVER red light for over-range, UNDER red light for open circuit and under-range

Environmental Parameters: Operating 0~60℃, Storage -40~85℃, humidity ≤ 80% RH without condensation, IP20 protection

Interface and Matching Base

Universal original screw terminal base: AS-8535-000, compatible with all B875 card base.

Core Function

Support flexible on-site configuration: 8-channel differential wiring enabled in harsh line-of-sight interference conditions, 16-channel single-ended wiring enabled for normal short-distance wiring; independent range configuration for each channel, compatible with two-wire transmitters and voltage sensors; hardware indicators for open circuit and over-range, with built-in simple automatic calibration function. Applicable scenarios

Refining, thermal power generation, water treatment Modicon 984 renovation project at the site features a mixed data acquisition station that simultaneously incorporates 4-20mA transmitters, voltage-type instruments, and long-distance measurement points susceptible to interference.

Operation and Maintenance

The module is directly inserted into the 800 rack I/O slots. The differential/single-ended mode can be switched via side-by-side dip switches, and the current sampling resistor can be selected through internal jumpers. The range can be configured via software without requiring hardware modifications. The red light indicates an alarm, prompting the priority troubleshooting of circuit breakage and instrument power supply. It can be used in conjunction with the B875-001/002/011/012/100/101/102 series of the same rack.