Utility Failures (Instrument Air, Power, Nitrogen)
Industrial analyzers rely on stable and clean utilities. Poor instrument air, unstable power, or unreliable nitrogen supply causes erratic operation, false alarms, and premature failures.
Field reality:
Analyzer problems often disappear when utilities are fixed —
without touching the analyzer.
Typical Symptoms
- Intermittent analyzer trips or resets
- Valve switching failures or timing errors
- Unstable readings or noisy signals
- Carrier gas or purge alarms
- Analyzer works intermittently or only during certain shifts
Common Utility-Related Causes
- Wet or oily instrument air
- Low or fluctuating air pressure
- Unstable or noisy power supply
- Improper grounding or earthing
- Interrupted or contaminated nitrogen supply
Frequent Utility Failure Modes
- Instrument air moisture: valve sticking and corrosion
- Air pressure drop: incomplete valve actuation
- Power dips: analyzer reboot and data loss
- Electrical noise: unstable analog signals
- Nitrogen loss: GC baseline drift and contamination
Correct Troubleshooting Order
1) Verify actual utility pressure and voltage at analyzer
2) Check air quality (dryness, oil, particulates)
3) Inspect filters, regulators, and dryers
4) Confirm grounding and power isolation
5) Verify nitrogen purity, pressure, and continuity
6) Only then troubleshoot analyzer hardware
Common Design & Installation Mistakes
- Sharing instrument air with heavy pneumatic loads
- No air quality monitoring
- No UPS for critical analyzers
- Undersized nitrogen cylinders or manifolds
- Poor earthing practices
Best Practices
- Provide analyzer-dedicated instrument air
- Install air dryers and coalescing filters
- Use UPS and surge protection
- Monitor nitrogen supply pressure continuously
- Treat utilities as part of the analyzer system