Description
- Model: ABB 086318-002 (Board) / 086318-501 (Assembly)
- Brand: ABB (formerly Bailey Controls)
- Series: Symphony Plus / Harmony / INFI 90
- Core Function: Power scaling and signal conditioning interface
- Product Type: Power Interface Module / PCB Assembly
- Key Specs: 24 V / 48 V DC input handling Rack-mounted High MTBF components
- Input Voltage: Dual redundant 24 V DC inputs (Standard)
- Output Signals: Scaled analog/digital power status signals
- Compatibility: Compatible with INFI 90 and Symphony Harmony racks
- Connector Type: Multi-pin edge connector (gold-plated)
- Mounting: Vertical rack-mount orientation
- Operating Temperature: 0°C to 70°C (32°F to 158°F)
- Signal Isolation: High-voltage surge protection integrated
- Form Factor: Standard Bailey-style rectangular PCB
- Test Points: Integrated hardware test points for voltage verification
- Configuration: Jumper-selectable voltage thresholds (Rev dependent)
ABB 086318-002 086318-501
ABB 086318-002 086318-501
Application Scenarios & Pain Points
In many chemical plants and pulp mills running on legacy Bailey INFI 90 systems, the 086318-002 serves as a silent sentinel for the rack power supply. If this board fails, the controller may receive “False Low Power” alarms, triggering an emergency shutdown of the entire rack. The biggest pain point is “aging drift”—as these boards hit 20+ years of service, the capacitors and resistors drift out of spec, causing intermittent bus errors that are a nightmare to track down during a live process.
Typical Application Scenarios:
- Chemical Processing – INFI 90 DCS Ensuring stable power rail signaling to the multi-function processors (MFP) in hazardous area control rooms.
- Pulp & Paper – Symphony Harmony Systems Used in the power distribution cabinets for paper machine logic where 24/7 uptime is the standard.
- Power Plant Control – Legacy Upgrades Serving as a bridge spare for plants that haven’t yet migrated to the full Symphony Plus architecture.
Case Study: The “Intermittent Ghost” in a Paper Mill
Background: A mill in the Pacific Northwest was experiencing random CPU resets on their Harmony rack. There was no clear pattern, and the power supplies themselves showed a steady 24.1 V DC.
The Problem: The diagnostics pointed to a “Power Fail” signal, even though the power was fine. We traced the issue to a 086318-002 board where a leaky capacitor was causing the “Power OK” signal to dip below the logic threshold for just a few milliseconds.
The Solution: Since the OEM lead time was “End of Life / Non-available,” we supplied a fully tested 086318-501 assembly from our surplus stock. We provided a Fluke multimeter verification report showing the voltage scaling was dead-on before shipping.
The Result: – Fix Time: 15 minutes to swap the board once it arrived.
- Outcome: The “Ghost Resets” vanished instantly. The mill saved an estimated $40,000 in lost production that would have occurred during the next expected trip.
Compatible Replacement Models
| Original Model | Replacement Model | Compatibility | Main Difference | Integration Effort |
|---|---|---|---|---|
| 086318-002 | 086318-003 | ✅ Direct Replace | Modernized components | Drop-in; zero config |
| 086318-002 | 086318-501 | ✅ Direct Replace | Refers to the full assembly | Drop-in |
| 086318-002 | SPASI series | ❌ Incompatible | Next-gen Symphony Plus | Requires full rack upgrade |
Troubleshooting Quick Reference
| Symptom | Likely Cause | Board Link? | Quick Check | Action |
|---|---|---|---|---|
| “Power Fail” Alarm | Voltage Scaling Drift | ✅ High | Measure the output signal at TP1. | If < 4.5V while 24V is present, replace. |
| Intermittent CPU Resets | Ripple on Signaling | ✅ High | Check for bulging caps on the PCB. | Replace board immediately. |
| Module Not Recognized | Edge Connector Corrosion | ⚠️ Medium | Inspect the gold pins for green/black oxidation. | Clean with contact cleaner/eraser. |
| No “Power OK” LED | Input Fuse Blown | ❌ Low | Check the inline fuse on the rack backplane. | Replace fuse; if it blows again, replace board. |
Integrator’s “Field Tips”:
- Pin Cleaning: These legacy Bailey boards use gold-plated edge connectors. In high-sulfur environments (like paper mills), they can develop a film. Before you assume the 086318-002 is dead, give the pins a gentle clean with a white block eraser. You’d be surprised how often that “fixes” a dead board.
- The “501” vs “002” Confusion: In the ABB world, the -002 is often the bare PCB part number, while the -501 is the completed assembly (including standoffs or specific firmware/rev). When ordering, always check the sticker on the component side of the board for the “501” number to ensure an exact match.
- Jumper Verification: Some revisions of these boards have jumpers for 24V or 48V logic levels. If your new board doesn’t work, don’t panic—check the jumper settings against the board you just pulled out.
