No big deal, It’s just a check meter
In many production and midstream facilities, check meters are often viewed as secondary devices—installed for monitoring, trending, or redundancy rather than custody transfer. Because of this perception, they are frequently excluded from routine proving programs. That approach can be costly.
Even though check meters may not be the primary billing meter, their accuracy directly impacts operational decisions, loss investigations, and confidence in the overall measurement system. Proving them is not just good practice—it is essential.
What Is a Check Meter?
A check meter is typically installed:
Downstream or upstream of a primary custody transfer meter
In parallel with another meter for verification
At production, LACT, or pipeline interconnects to validate performance
While it may not generate the invoice, it serves as the system’s lie detector—confirming that the primary meter is behaving as expected.
Early Detection of Meter Drift and Failure
Meters do not usually fail catastrophically. More often, they slowly drift out of tolerance due to:
Wear on internal components
Coating or fouling
Changes in fluid properties
Gas entrainment or solids
A proved check meter provides a reliable comparison point. When discrepancies appear between meters that were both recently proved, operators can identify issues before volumes, allocations, or revenue are affected.
Without proving, differences are often dismissed as “process variation” when they are actually measurement errors.
Validation of the Entire Measurement System
Check meters help validate more than just another meter—they help confirm:
Flow profile stability
Proper meter sizing
Instrument health (temperature, pressure, density)
Prover and proving methodology integrity
When a check meter is proved and aligned with expectations, it builds confidence in the entire measurement loop. When it is not, it introduces uncertainty that is difficult to defend during audits or disputes.
Supporting Allocation, Balancing, and Loss Control
Even when not used for custody transfer, check meters are often relied upon for:
Production allocation
Tank-to-meter reconciliation
Line balance calculations
Loss and gain investigations
Using an unproved check meter for these purposes undermines the credibility of the data. Proving ensures that decisions based on those numbers are grounded in verified accuracy rather than assumption.
Regulatory and Audit Readiness
Regulators and auditors increasingly expect consistency across measurement devices—not just the billing meter. While standards such as API MPMS and BLM regulations emphasize custody transfer meters, they also stress measurement system integrity and traceability.
A documented proving history for check meters demonstrates:
Due diligence
Strong measurement controls
A proactive approach to compliance
This can significantly reduce scrutiny during audits or inspections.
Small Cost, Large Risk Reduction
The cost to prove a check meter is typically minor compared to:
Volume misallocation
Undetected losses
Extended troubleshooting
Disputes with partners or purchasers
Proving check meters is a low-cost insurance policy that protects both operational efficiency and financial accuracy.
Final Thoughts
Check meters may not generate the invoice—but they protect it.
By including check meters in your proving program, you strengthen confidence in your data, catch problems early, and maintain a higher standard of measurement integrity across your operation. In an industry where small percentage errors can translate into large financial impacts, verified accuracy is never optional.
