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Phone: +86 16626708626Description
Key Technical Specifications
- Manufacturer: Rolls-Royce
- Model: UN 925
- System Family: UMAS-V marine automation
- Product Type: Buzzer panel / panel controller
- Supply Voltage: 24 V DC ±20%
- Network Interface: Profibus
- Address: ADR 18
- Application: Marine alarm and control system
- Weight: 1.920 kg
- Condition: Used
- Compatibility Note: Verify exact panel type and address before installation
Product Introduction
Rolls-Royce UN 925 is a marine buzzer panel used in UMAS-V automation systems. It runs on 24 V DC and, in the documented Profibus version, uses address 18.
This is a part you match by exact type and system interface, not by faceplate alone. Check the removed unit’s label, address, and wiring before ordering.
Troubleshooting Quick Reference
| Symptom | Possible Cause | Relevance to This Part | Quick Check Method | Recommendation |
|---|---|---|---|---|
| No buzzer or alarm output | Missing 24 V DC supply or failed upstream circuit | ✅ High | Measure 24 V DC at the panel input terminals | Check supply and fuse path before replacing the panel |
| Profibus communication fault | Wrong address, bad bus wiring, or incompatible panel variant | ✅ High | Verify ADR 18 and inspect bus cable termination | Confirm network settings and wiring first |
| Wrong alarm indication | Configuration mismatch or wiring error | ✅ High | Compare current wiring and address to the removed panel | Mirror the original setup exactly |
| Intermittent operation | Loose connectors, vibration, or oxidation | ⚠️ Medium | Reseat connectors and inspect pins for corrosion | Clean and secure the installation |
| Panel dead after swap | ESD damage or incorrect installation | ✅ High | Check for supply at the board and inspect handling marks | Replace only after verifying power and ESD handling |
If you are stuck, send photos of the label, connectors, and alarm logs to technical support.
- UN 925
- UN 925
Frequently Asked Questions
Q: Is UN 925 a marine control panel?
A: Yes. The available market information points to a Rolls-Royce UMAS-V marine buzzer/panel controller. Exact label matching matters.
Q: Is this the Profibus version?
A: The documented listing shows a 24 V DC Profibus version with address 18. That said, always match the exact label on your removed unit before ordering.
Q: Is this new or used?
A: The market data I found indicates used condition. Used usually means removed from service and resold, so ask for test status and photos.
Q: Can I swap it without reprogramming?
A: Sometimes, but not always. Copy the original address, wiring, and any site settings before removal so you do not create a new fault during the swap.
Q: Is it hot-swappable?
A: Do not assume so. Unless the OEM documentation says live replacement is allowed, shut the system down first.
Q: Why is it cheaper than factory-new stock?
A: Because used surplus is priced lower than new OEM inventory. The lower price is tied to condition and availability, not necessarily to whether the panel works.
Q: What should I verify before buying?
A: Check the exact model, 24 V DC supply requirement, Profibus address, connector layout, and physical condition. Those are the details that prevent the expensive mistakes.
