Custody Transfer Water Cut Measurement You Can Rely On
Low-range BS&W meters for LACT units, truck unloading, and fiscal metering applications. ±0.01% accuracy where it matters most.
The Challenge
Custody transfer is the point where crude oil changes ownership. Every fraction of a percent of water content directly affects the financial value of the transaction. Inaccurate BS&W measurement at LACT (Lease Automatic Custody Transfer) units leads to disputes, penalties, and lost revenue.
Financial Exposure
At custody transfer points, a 0.1% error in BS&W measurement on a 10,000 barrel/day lease can cost tens of thousands of dollars per month.
Standards Compliance
API and ASTM standards require accurate BS&W measurement for fiscal metering. Instruments must provide traceable, repeatable results.
Automatic Divert
LACT units must automatically divert off-spec crude when water content exceeds contractual limits — requiring fast, reliable measurement.
Low Water Cut Precision
Custody transfer typically involves clean, low-water-cut crude (<1%). Instruments must resolve tiny changes with high precision.
How Zelentech Solves It
The ZT-100 low-range water cut analyzer delivers ±0.01% accuracy in the 0–25% measurement range — the precision required for custody transfer and fiscal metering applications. Installed directly in the LACT unit pipeline, it provides continuous BS&W data for automatic divert control and net oil volume calculation.
The F-Series spool-piece design ensures full-bore measurement with no flow restriction, while the retractable I-Series allows probe installation and removal under pressure for maintenance without shutdown.
HART and Modbus RTU outputs feed directly into flow computers and SCADA systems. Combined with a ZTMX Static Mixer upstream, the ZT-100 ensures the sample is fully homogenised before measurement — eliminating stratification errors.
±0.01% Accuracy
Low-range precision for clean crude where every hundredth of a percent affects the financial settlement.
Automatic Divert Integration
4–20mA output drives divert valves and flow computers for automatic off-spec crude rejection.
Upstream Mixing
Pair with ZTMX Static Mixer for homogenised flow, eliminating water stratification before the measurement point.
Key Specifications
| Measurement Range | 0–25% water cut (low range) |
| Accuracy | ±0.01% |
| Flange Rating | ANSI 150# to ANSI 1500# |
| Certification | ATEX / IECEx Zone 1 & 2 |
| Output | 4–20mA + HART + Modbus RTU |
| Response Time | 1 second |
| Materials | 316L SS / Carbon steel |
Recommended Products
ZT-100 F-Series
Full-bore spool-piece design for LACT units and mainline custody transfer measurement.
View product →
ZTMX Static Mixer
Install upstream of the water cut analyzer to homogenise the flow and eliminate stratification errors.
View product →
LACT & ACT Units
Complete custody transfer systems with integrated water cut measurement, flow metering, and automatic divert.
View systems →Equipping a LACT Unit or Custody Transfer Skid?
Our engineers can recommend the right ZT-100 and ZTMX configuration for your pipe size, pressure class, and accuracy requirements.
