Product Overview
The Honeywell Enraf Smart Servo 954 is a high-precision automatic tank gauge for measuring liquid level, interface level, product density, water bottom and temperature in industrial storage tanks.
Its servo-operated displacer and patented force-transducer technology provide accurate and repeatable measurement under demanding process conditions, including pressurised, cryogenic and chemical applications.
Key Features
✔ High-precision servo measurement technology
✔ Liquid-level measurement
✔ Oil-and-water interface measurement
✔ Product density measurement and profiling
✔ Direct water-bottom measurement
✔ Product and vapour-temperature measurement
✔ Accuracy up to ±0.4 mm
✔ Repeatability of 0.1 mm or better
✔ Measuring ranges up to 150 m
✔ Operating pressure up to 40 bar
✔ Adaptive dynamic compensation
✔ Local display and advanced diagnostics
✔ Servo Auto Test functionality
✔ SIL-certified alarm and output options
✔ 4–20 mA and HART device integration
✔ Custody-transfer configurations available
Technical Specifications
| Specification | Details |
|---|---|
| Measuring principle | Servo-operated displacer with force transducer |
| Standard measuring range | Up to 27 m |
| Extended ranges | 37 m, 40 m and 45 m |
| Cavern configuration | Measuring wire up to 150 m |
| Level accuracy up to 40 m | Better than ±0.4 mm |
| Level accuracy at 45 m | Approximately ±1 mm |
| Interface accuracy | Better than ±2 mm |
| Density accuracy | Better than ±3 kg/m³ |
| Temperature accuracy | Better than ±0.1°C |
| Repeatability | 0.1 mm or better |
| Maximum process pressure | Up to 40 bar, configuration dependent |
| Measuring-wire materials | AISI 316, Hastelloy C22, tantalum, tungsten or Invar |
| Outputs | 4–20 mA and programmable relay options |
| Certification | OIML R85 and safety-related options |
Measurements Supported
- Product level
- Ullage
- Oil-and-water interface
- Water bottom
- Product density
- Density profiling
- Product temperature
- Vapour temperature
- Average tank temperature
- High-level and overfill alarms
Typical Applications
- Crude-oil storage tanks
- Refined petroleum tanks
- Chemical storage tanks
- LPG and LNG installations
- Ammonia tanks
- Cryogenic storage
- Pressurised tanks
- Tank farms and terminals
- Custody-transfer systems
- Cavern-storage applications
Industries
✔ Oil and gas
✔ Refineries
✔ Petrochemical
✔ Chemical
✔ Tank terminals
✔ LNG and LPG
✔ Marine terminals
✔ Cryogenic storage
✔ Custody transfer

