Product Core Brief

• Model: IMDS003
• Brand: ABB Bailey
• Series: INFI 90 / Symphony / Symphony Harmony
• Core Function: Digital output slave module that switches discrete 24 VDC loads under controller command in Bailey DCS racks.
• Product Type: Digital Output Slave Module
• Key Specs: 24 VDC operation | discrete digital output | slave module on I/O expander bus
• Condition: New Original / New Surplus (depending on stock)

Key Technical Specifications

• Manufacturer: ABB (Bailey INFI 90 / Symphony product line)
• Part Number:
• Product Type: Digital Output Slave Module
• System Compatibility: ABB INFI 90, Symphony, Symphony Harmony DCS
• Primary Function: Switches discrete digital outputs for relays, solenoids, indicators, and similar field devices
• Operating Voltage: 24 VDC (typical range 19.2 to 28.8 VDC)
• Power Consumption: approx. 4 W
• Communication Interface: I/O expander / slave bus within Bailey HCU architecture
• Mounting Style: Standard Bailey module for MMU rack installation
• Typical Operating Temperature: -25 to +70 °C (catalog listing)
• Dimensions: approx. 140 × 100 × 70 mm (catalog listing)
• HS Code: 853710 (electrical control panels / assemblies)

Product Introduction (No Fluff)

The ABB IMDS003 is a digital output slave module used in Bailey INFI 90, Symphony, and Symphony Harmony DCS systems. It receives discrete output commands from the controller and switches 24 VDC field loads such as relays, solenoid valves, and status indicators.

Because it operates as a slave module on the I/O expander bus, replacement is straightforward when the correct slot address and termination wiring are verified. This unit is commonly stocked as an OEM replacement part for plants maintaining legacy Bailey I/O racks without migrating the entire controller platform.

QA & Testing SOP (Dynamic & Transparent)

This is a digital output slave module, so testing focuses on output switching, bus communication, and field-side isolation.

1. Incoming visual inspection: Check the module housing, edge connector, status LEDs, and PCB for corrosion, burnt components, or prior repair marks.
2. Bus communication test: Seat the module in a known-good Bailey MMU and verify it registers on the slave/I/O expander bus without fault indicators.
3. Output switching test: Force each digital output on and off from the controller or test rack, then verify the corresponding LED and output voltage with a Fluke multimeter.
4. Field-load verification: Confirm the module can drive a representative 24 VDC load without excessive voltage drop or overheating.
5. ESD-safe handling and packing: Store and ship in anti-static packaging; handle by the module frame and avoid contact with the edge connector.

Installation Pitfalls & Guide (Engineer to Engineer)

❗ Do not assume all “IMDS” modules are the same. Bailey uses similar prefixes for digital input, digital output, and mixed I/O slaves. Verify the exact part number before swapping.

❗ Check field wiring polarity before energizing. Reversed 24 VDC wiring or a shorted solenoid can damage the output driver even if the module appears functional on the bus.

❗ Confirm slot addressing and bus position. A mis-seated slave module may power up but fail to respond to controller output commands.

❗ Watch total rack power draw. Adding multiple output modules increases 24 VDC demand; undersized power distribution can cause voltage sag and intermittent faults.

Replacement steps:

1. Pre-install: Document slot location, record forced output states, and notify operations before removing the module.
2. Removal: Place affected outputs in a safe state, disconnect field wiring if required, and remove the failed module.
3. Install: Seat the new IMDS003, verify retention, reconnect field wiring, and confirm correct slot alignment.
4. Power-on test: Check module LEDs, verify bus communication, and test each output under controlled conditions.

Technical FAQ

1. Is the IMDS003 still available?
Yes, but it is a legacy Bailey module. Availability depends on inventory condition. We carry new original and new surplus stock.

2. Can I substitute it with another IMDS module?
Not automatically. Digital input, digital output, and mixed I/O slaves are not interchangeable. Confirm the exact part number, channel count, and voltage rating before replacement.

3. Does this module need firmware loading?
No. The IMDS003 is a slave I/O module. Configuration and control logic reside in the controller; the module responds to bus commands and switches discrete outputs.

4. What warranty do you offer?
Standard warranty is 12 months unless otherwise stated. For surplus stock, warranty terms are confirmed at quotation.

5. Can you offer volume pricing?
Yes. Pricing is flexible for multi-unit orders, rack rebuilds, or long-term spare kits. Send the required quantity and condition preference for a direct quote.