Model Interpretation

AS: Modicon Automation System

B840: 8‑point reed relay output module

108: 8‑point, NO/NC configurable variant

Technical Parameters

Outputs: 8 channels, reed relay, isolated, NO/NC selectable per channel

Switching Voltage:

AC: 12–250VAC

DC: 12–300VDC

Switching Current: 2A per point (resistive load)

Max Power Rating: 100VA (AC); 60W (DC)

Max Module Current: 24A

Response Time:

OFF→ON: ≤6ms (2ms typical)

ON→OFF: ≤6ms (2ms typical)

Isolation: 1500VAC channel‑to‑backplane

Backplane Power: +5V 67mA; +4.3V 400mA

Operating Temp: 0°C to +60°C

Storage Temp: -40°C to +85°C

Humidity: 5%–95% non‑condensing

Weight: ≈1.2kg (2.6lbs)

Dimensions: 50×119×125mm

Origin: France

Interface & Configuration

Backplane: Modicon 800/984 I/O bus

Terminals: Screw terminals (8 relay outputs, common per channel)

Indicators: 8 LEDs (ON when relay energized)

Fuses: None (relay inherently self‑protecting)

Wiring: 0.5–2.5mm² copper wires

Terminal Connector: AS‑8534‑000

Configuration: NO/NC jumper per channel

Core Functions

NO/NC Selectable: Each channel independently configurable for normally open or normally closed

Universal Relay Output: Controls AC/DC loads with dry contacts, no voltage restriction

Isolated Channels: Each output fully isolated, minimizing cross‑talk and fault propagation

Fast Switching: 2ms typical response for high‑speed on/off control

LED Status: Individual channel LEDs for quick visual diagnostics

Applications

Systems: Modicon 800, 984, 300‑series PLCs

Industries: General automation, packaging, material handling, textile machinery

Use Cases: Motor starters, solenoid valves, contactors, alarms, lamps, and low‑power AC/DC loads

Compatibility

Racks: Modicon 800/984 8/11‑slot backplanes

CPUs: AS‑984B‑128, PC‑E984‑685, AS‑9370‑001

Software: Concept, ProWORX 32, P190