Foxboro SAC-RL100-M11 Relay Output Module

Technical Specifications:

• Number of Channels: 16 SPDT dry contact relay outputs
• Contact Rating: 5 A at 250 V AC (resistive load); 5 A at 30 V DC (resistive load)
• Contact Type: SPDT (Form C) — Common, Normally Open (NO), Normally Closed (NC)
• Coil Voltage: 24 V DC (nominal), range 18–30 V DC
• Isolation Voltage: 1500 V DC between channels and backplane
• Response Time: < 10 ms (typical)
• Operating Temperature: 0°C to +60°C (+32°F to +140°F)
• Storage Temperature: -40°C to +85°C (-40°F to +185°F)
• Humidity: 5% to 95% RH (non-condensing)
• Power Consumption: < 8 W (typical, all relays energized)
• Dimensions (W x H x D): 25 mm x 220 mm x 160 mm (approximate, DIN rail module)
• Weight: Approximately 350 grams
• Backplane Connection: I/A Series standard backplane connector

Functional Features:

• 16 Independent Relays: Each relay is individually addressable and controllable by the I/A Series controller
• Dry Contact Outputs: No voltage supplied by the module — field wiring provides the switched voltage
• LED Indicators: Per-channel LED indicates relay state (ON = green, OFF = dark)
• Backplane Powered: Draws all operating power from the I/A Series backplane — no external power required
• Hot-Swappable: Module can be replaced without shutting down the I/A Series controller (with proper procedure)

Material Composition:

• Housing: Flame-retardant ABS plastic (UL 94 V-0)
• Relay Contacts: Silver-cadmium oxide (AgCdO) for high reliability and low contact resistance
• PCB: FR-4 epoxy glass with conformal coating
• Connectors: Gold-plated edge connector for backplane; screw terminals for field wiring
• Terminal Blocks: Phosphor bronze, tin-plated

Structural Characteristics:

• Form Factor: DIN rail mountable module for I/A Series I/O cabinet
• Mounting: Standard 35 mm DIN rail inside I/O cabinet
• Terminal Layout: 16 groups of 3 terminals per channel (COM, NO, NC)
• Status LEDs: 16 individual LEDs on front face, one per channel

Working Principle:
The I/A Series controller sends a digital command via the backplane bus to the SAC-RL100-M11 module. The module’s internal decoder activates the corresponding relay driver circuit, which energizes the 24 V DC relay coil. The relay contacts switch from NC to NO (or vice versa). The per-channel LED illuminates when the relay is energized. The dry contact outputs are completely isolated from the module’s internal circuitry — the field device provides its own voltage/current through the relay contacts.

Advantages / Highlights:

• 16 relay outputs in a single module — reduces cabinet space and wiring complexity
• 5 A contact rating handles solenoid valves, small motors, and indicator lamps directly
• Dry contact design provides maximum flexibility — any voltage/current within rating can be switched
• 1500 V DC isolation ensures noise immunity and ground loop elimination
• Backplane-powered — no external power supply needed
• Hot-swappable with I/A Series system

Applicable Industries:

• Oil and Gas (valve control, pump interlocks)
• Chemical Processing (solenoid valve sequencing, alarm annunciation)
• Power Generation (breaker control, pump sequencing)
• Water Treatment (valve and pump control)
• Manufacturing (conveyor control, machine interlocks)

Installation Requirements:

• Install on 35 mm DIN rail inside the I/A Series I/O cabinet
• Ensure backplane connector is fully seated — improper seating causes communication failure
• Connect field device wiring to COM, NO, and NC terminals for each channel
• Do not exceed 5 A per contact — use external contactor for higher loads
• Do not apply backplane power to field wiring — relays are dry contact only
• Maintain minimum 10 mm clearance above and below module for ventilation

Usage Precautions:

• Verify relay contact rating (5 A / 250 V AC) before connecting inductive loads — use snubber circuits for inductive loads
• Do not exceed 30 V DC coil voltage — will damage relay driver circuitry
• For inductive loads (solenoids, relays), install a flyback diode across the load to suppress voltage spikes
• Do not mix AC and DC loads on the same relay contact without verifying rating
• Replace module immediately if any LED fails to illuminate when commanded