www.sentech.no

The Sentech Water Cut Meter offers some unique advantages over the more well-known brands:

• Full-bore measurement in any pipe diameter

• 0 – 100% water-in-oil range for all sizes

• Completely non-intrusive – introduces no pressure drop

• Suitable for two-phase and multiphase flow

• Averages measurements at multiple locations around the pipe

• Provides detection of oil/water distribution as well as water cut

The Sentech Water Cut Meter is the only brand on the market that can be installed in-line and measure

0 – 100% Water across the whole circumference of any pipe diameter – even 24” and larger.

Typical Applications

The Sentech Water Cut Meter measures water content in any oil based liquid, as well as in multiphase

flow (oil, water, gas). Numerous applications can be found within Oil & Gas production and processing,

as well as in industries such as Marine, Chemicals, Food & Beverage etc.

• Individual Oil & Gas well monitoring – for instant notification of changes in water production

• Slug detection – for early warning before excess water is hitting the process facilities

• Production separator inlet monitoring – for early action before water level starts to increase

• Production separator oil outlet monitoring – for continuous assessment of separator efficiency

• Coalescers, centrifuges and dehydrators – for rapid identification of bad performers

• Heavy oil (incl. oil sands) – when viscosity, specific gravities and solids prohibit other technologies

• Subsea production – for identifying which wells are causing increased water on the surface

• Ship fuel monitoring – for detecting water or verifying optimized water content

Due to its ability to measure the water

fraction also in the presence of gas,

the Sentech Water Cut Meter is a cost-

effective alternative to conventional

multiphase meters for monitoring of

individual wells. This applies especially

when it is more important for the

operator to learn immediately when a

well changes behavior or starts to

produce more water, rather than

knowing the exact flow rates of oil, gas

and water from each well.

SENTECH WATER CUT METER

TOP: 24" meter with 32 sensors

in heavy oil application

ABOVE: 4" meter with 4 sensors

RIGHT: 4" meter with 8 sensors

www.sentech.no

Design Flexibility

The Sentech Water Cut Meter is normally supplied as a flanged spool piece for in-line installation in any

pipe size. This allows operator to take advantage of existing pipe routing, and avoids the requirement for

extra piping, flanges and valves for bypass arrangements.

For 12" meters and smaller, the standard design is a one-piece spool (incl. process connections),

machined from a single rod of 316L stainless steel. This avoids the additional project execution efforts

relating to welding procedures, qualifications, testing and documentation.

The table below indicates the available pipe diameters, schedules, materials and process connections.

These standard specifications cover the majority of applications, while customized designs can be made

to suit other, particular project requirements.

Measurement Principle

As most other water cut meters on the market, the Sentech Water Cut

Meter takes advantage of the vastly different electrical properties between

hydrocarbons and water, which allows detection and measurement of even

tiny amounts of water in oil.

The Sentech Water Cut Meter utilizes multiple SeCaP sensors to both

measure % Water and determine how the water is distributed in the pipe.

While other capacitance based water cut meters use a pair of electrodes,

SeCaP is a single electrode sensor, operating around 20 MHz. The ultra-

robust ceramic front of the sensor isolates the electrode electrically from

the flow. Thus, the signal never is never shorted – even when the flow turns

water continuous.

The number of SeCaP sensors is adapted to customer preference and

process conditions, only limited by physical space around the

circumference of the pipe. The instantaneous readings from each sensor

are averaged – both across the circumference of the pipe and over time.

Although the highest accuracy is always achieved in well mixed flow, the

Sentech Water Cut Meter is still able to measure in vastly unstable flow

regimes (slugging) – and even on horizontal pipes with stratified flow.

Special Models

The Sentech Water Cut Meter can also be supplied as an intrusive or non-intrusive probe with a single

SeCap sensor. Since water and oil is never perfectly mixed, single-point measurement rarely offers the

same accuracy as full-bore measurement. However, it may be a good option where an indication of

changes in water cut is more important than the absolute % Water.

Sentech AS further offers a compact subsea version of its water cut meter, with the same performance

specifications as the traditional meter.

The SeCaP sensor with

ceramic front and circuit

board with embedded

oscillator and temperature

sensor measures less than

1" in all directions

Single sensor insertion probe

water cut meter

Subsea water cut meter

with 6 sensors

www.sentech.no

System and Installation

The Sentech Water Cut Meter is certified as an Ex ia system from Hazardous Area to Safe Area.

A full Sentech Water Cut Meter system consists of the following components:

• In-line meter body with SeCaP sensors, oscillator and temperature sensor (in Hazardous Area)

• Controller Unit in separate enclosure, NEMA 4X (in Hazardous Area, max. 5 m from meter body)

• Analyzer Interface cabinet, NEMA 12 (in Safe Area) with barriers for power and communication

The Safe Area Analyzer Interface cabinet is optional, while the barriers are required to maintain validity

of the Ex-ia certificate. For installation of the barriers in existing Safe Area cabinet, Sentech AS will supply

a DIN rail with the required components, along with installation and wiring instructions.

Measurement Accuracy

www.sentech.no

Sentech Water Cut Meter datasheet

The specifications below apply for the traditional in-line (spool piece) version of the Sentech Water Cut

Meter. The table indicates the standard options for material, sizes and process connections.

For other specifications, contact Sentech AS (info@sentech.no).

MECHANICAL SPECIFICATIONS – METER BODY (SENSOR UNIT)

Pipe diameter (in-line) 2" – 24" and larger, sch. 40 - 80

Material SS 316L, NACE MR-0175

Construction Machined, no welds (12" and smaller)

Process connections Flanged ANSI/API, 150# - 900#, RF/RTJ

Wetted parts SS 316L, Ceramic

Number of sensors 2 – 16 (typ.)

Design temperature 125°C, 175°C, 225°C

Design pressure Up to 450 bar (depending on pipe schedule and flange rating)

Enclosure protection IP66 (sensor elements & terminals housing)

Protective coating Not applicable

MECHANICAL SPECIFICATIONS – CONTROLLER UNIT ENCLOSURE

Dimensions 353 x 175 x 108 mm3 (13.9" x 6.9" x 4.3")

Material SS 316

Mounting Stand-alone

Enclosure protection IP66/IP67

Protective coating Not applicable

ELECTRICAL SPECIFICATIONS

Hazardous Area classification

Ex ia protection from Sensor Unit to Safe Area Analyzer Interface cabinet Meter body (Sensor Unit): ATEX/IECEx II 1/(1)G Ex ia/[Ex ia] IIB T4-T2 Ga Controller Unit enclosure: ATEX/IECEx Ex ia IIB T4 Ga -40°C ≤ Ta ≤ +60°C Analyzer Interface cabinet: Must be placed in Safe Area

Ambient temperature -40 to 60°C

Outputs 4–20 mA (% Water), RS485 Modbus RTU

External power supply 120/230VAC, 24VDC to Safe Area Analyzer Interface cabinet

Safe Area power barrier Pepperl & Fuchs KFD0-SD2-Ex1.10100 (mandatory for Ex ia certificate)

Power consumption < 10 W

Cable entry Meter body sensor elements & terminals housing: M16 Controller Unit enclosure: M16, M20

Maximum cable length Meter Body to Controller Unit enclosure: 5 m Controller Unit to Safe Area barrier modules: 700 m

PERFORMANCE SPECIFICATIONS

Primary measurement % Water (of total volume of Water + Oil + Gas)

Measurement principle Single Electrode Capacitance

Measurement range 0 – 100% (4–20 mA output can be configured to other ranges)

Uncertainty

0 – 2% Water: ± 0.1% abs. 2 – 10% Water: ± 5% rel. (of reading) 10 – 50% Water: ± 0.5% abs. (in oil-continuous flow) 50 – 100% Water: ± 1% abs. (in water-continuous flow) With 10 – 90% Gas: ± 1-2% abs. (depending on % Water and % Gas) (Above specifications assume well mixed flow)

Sensitivity 0 – 2% Water: ± 0.01% abs.

Repeatability ± 0.01% abs.