How to Configure an AGA-3 Orifice Meter on the Emerson ROC800
Key Takeaway
Step-by-step AGA-3 orifice meter configuration on the ROC800 — pipe/orifice parameters, input assignments, gas composition, compressibility, and archive setup.
Quick Answer
An AGA-3 meter run on the ROC800 calculates natural gas flow through an orifice plate per AGA Report No. 3. Configure in ROCLINK 800 under Meter Runs: enter pipe ID, orifice bore, assign DP/SP/temperature inputs, enter gas composition, and select AGA-8 Detail compressibility for custody transfer. If your firmware only offers NX-19 compressibility, that is a compliance risk — most current gas contracts require AGA-8 Detail.
How Do You Create an AGA-3 Meter Run?
- Navigate to Meter Runs in ROCLINK 800
- Select an unused meter run slot
- Set Meter Type to AGA-3 Orifice
- Enter pipe ID and orifice bore diameter
- Select pipe and orifice materials
- Assign DP, static pressure, and temperature AI channels
- Enter gas composition (mole % for each component)
- Set base conditions (14.73 PSIA, 60°F)
- Select compressibility method (AGA-8 Detail recommended)
- Write configuration and verify calculated flow rate
Which Compressibility Method?
- AGA-8 Detail — Most accurate, required for custody transfer
- AGA-8 Gross — Acceptable for non-fiscal measurement
- NX-19 — Legacy only, not recommended for new installations
For comparison, see AGA-3 on ABB Totalflow and ROC archive configuration for meter run records.
Frequently Asked Questions
Three analog inputs: differential pressure (inches H2O or kPa), static pressure (PSIA or kPaA), and flowing temperature (°F or °C).
Orifice bore diameter divided by pipe internal diameter. ROC calculates it automatically. AGA-3 requires 0.15-0.75 range.
AGA-8 Detail for new custody transfer. AGA-8 Gross for non-fiscal. NX-19 is legacy only.