Technical Specifications:

• Number of Channels: 8 channels (digital I/O)
• Input Type: Dry contact (volt-free contact), 24 V DC (sink/source selectable)
• Output Type: Relay output (SPDT) — indicated by “S33”
• Input Voltage: 24 V DC (sink or source)
• Input Current: 5 mA (typical)
• Output Contact Rating: 2 A at 250 V AC (resistive), 30 V DC (resistive)
• Output Type: SPDT (Single Pole Double Throw) relay
• Response Time: 10 ms (input to output, typ.)
• Isolation: 500 V AC between channels, 500 V AC channel to backplane
• Power Consumption: 3.5 W (typical)
• Operating Temperature: 0 to 55 °C (32 to 131 °F)
• Humidity: 5 to 95% RH (non-condensing)
• Mounting: DIN rail or direct mounting in FA-M3 rack
• Dimensions: 25 × 90 × 130 mm (W × H × D) approximately
• Weight: Approximately 150 g (0.33 lb)

Functional Features:

• 8 Discrete Channels: Independently configurable as input or output per channel
• Dry Contact Input: Compatible with volt-free contacts from field switches, limit switches, and proximity sensors
• Relay Output: SPDT relay suitable for driving solenoid valves, indicator lamps, and small motors
• LED Indicators: Per-channel LED for input status (green) and output status (red)
• Online Configuration: Channel direction (input/output) configurable via FA-M3 programming software
• Fail-Safe Option: Output default state (ON/OFF) configurable for safety applications
• Short Circuit Protection: Built-in protection on all input channels

Performance Parameters:

• Insulation Resistance: 100 MΩ minimum at 500 V DC
• Dielectric Strength: 1500 V AC for 1 minute (input to output, input to backplane)
• Common Mode Rejection: 120 dB minimum at 50/60 Hz
• Backplane Communication: FA-M3 high-speed serial bus
• Update Rate: 10 ms (all 8 channels)
• MTBF: 100,000 hours (minimum)

Structural Features:

• FA-M3 standard module format
• Front-facing LED indicators per channel (8 green for input, 8 red for output)
• Front-facing terminal blocks for field wiring (screw terminals)
• Rear-facing backplane connector for FA-M3 bus connection
• DIN rail clip or screw mounting option
• Module identification label on front face

Working Principle:
The SDV144 module interfaces discrete field signals with the FA-M3 central processor via the backplane bus. For input channels: field dry contacts or 24 V DC signals are connected to the input terminals. The input circuit conditions the signal (filters, debounces) and sends the digital state (ON/OFF) to the FA-M3 processor. For output channels: the FA-M3 processor sends a digital command to the module, which energizes or de-energizes the corresponding SPDT relay. The relay contacts switch the external load (solenoid, lamp, etc.). All 8 channels are scanned every 10 ms.

Advantage Highlights:

• 8 Channels in One Module: Reduces rack space and wiring compared to individual I/O modules
• Relay Output: SPDT contacts provide both NO and NC switching for versatile control
• Dry Contact Compatibility: Works with any field switch regardless of voltage
• FA-M3 Integration: Seamless integration with Yokogawa FA-M3 DCS platform
• Per-Channel LEDs: Instant visual status indication for troubleshooting
• Online Reconfiguration: Change input/output assignment without removing the module

Applicable Industries:

• Oil refineries (pump status, valve position, alarm indication)
• Chemical plants (interlock systems, status monitoring)
• Power plants (breaker status, turbine auxiliary systems)
• Water treatment (pump control, valve position)
• Manufacturing (conveyor status, machine interlocks)
• Building automation (damper position, fire alarm interface)

Installation Requirements:

• Install in FA-M3 compatible rack or DIN rail enclosure
• Ensure ambient temperature remains within 0 to 55 °C
• Use 22–16 AWG wire for field connections (dry contact inputs)
• Use 22–14 AWG wire for relay output connections (up to 2 A)
• Maintain minimum 50 mm clearance between modules for airflow
• Ground the module chassis to plant earth
• Label all field wiring per I/O list for maintenance clarity

Usage Precautions:

• Do not exceed 2 A at 250 V AC or 30 V DC on any relay output channel
• Verify input type (sink vs. source) matches field device wiring before energizing
• Use flyback diodes across DC solenoid loads to suppress relay contact arcing
• Replace the entire module if any channel shows persistent failure (not field-repairable)
• Ensure backplane connector is fully seated before applying power
• Do not mix AC and DC loads on the same relay channel