MERLIN Cathodic Protection Monitoring2018-07-19T10:28:08+00:00

Everything You Need From a Remote Cathodic Protection Monitoring System

Cathodic Protection (CP) is an important method of preventing corrosion on buried metal pipelines. But it must be applied at the correct level. Every pipeline operator must carry out regular measurements of CP – at rectifiers or solar stations and at CP tests points (in impressed current systems) and at sacrificial anodes (in galvanic systems).

Some key pipelines – crossing main roads, rivers or centres of population – may have additional protection against corrosion in the form of a sleeve filled with an inert gas (Nitrogen). The gas pressure in the sleeve has to be maintained above a specific threshold, which requires regular checks.

Collecting and analysing field measurements is labour-intensive and costly. And (very importantly) they can only be reactive – problems can lie undetected for long periods, during which the pipeline is insufficiently protected.

Introducing MERLIN

Abriox has developed the MERLIN system with input from pipeline operating companies and independent CP consultants. The MERLIN system remotely monitors cathodic protection levels at rectifiers and test points along pipelines, and also the pressure within nitrogen sleeves.

All measured data is automatically transmitted in a management report to the system HQ where it is displayed and archived in Abriox’s CPSM software or online via iCPSM. The system is proactive - identifying potential corrosion problems wherever and whenever they occur and alerting the operator immediately.

MERLIN Remote Cathodic Protection Monitors (also known as Remote Monitoring Units - RMUs) are commonly used at:

  • Rectifiers and Solar Stations - measuring electrical supply, voltage output, current output, ON and OFF potentials and also interrupting the current output for above ground surveys
  • Test Stations, CP Posts and Riser Posts – measuring pipe to soil ON potentials, instant OFF potentials, coupon currents
  • On-shore Tanks, Sacrificial Anodes, Isolation Joints and Critical Bonds
  • Pipeline Sleeves - measuring nitrogen/inert gas levels

Benefits

MERLIN has major economic, operational, safety and environmental benefits and has been installed on every continent, providing significant cost savings and making our customers’ operations more efficient.

MERLIN IS THE COMPLETE SOLUTION FOR 24/7 CATHODIC PROTECTION MONITORING

The most cost-effective, completely wireless remote monitoring system for the oil, gas, petrochemical pipeline protection industries. Contact us today for more information on how Abriox remote monitoring systems can improve your network management.

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Innovative Design

Through careful consideration of what pipeline operators require from a monitoring system, Abriox has been able to combine low power consumption electronics with remote telemetry to create a compact, affordable package offering all the key CP measurements.

Our design is intelligent, yet practical. Some of the points our customers repeatedly comment on are:

  • The ease of installation of our monitors. Within a few minutes of being on site it is possible to install, commission (in the software) and take the first measurements from a MERLIN monitor. No specialist equipment is required, simply standard tools and a cellphone.
  • The ability to get readings in the field from our monitors. Transformer Rectifier monitors are continuously powered, so technicians can get readings sent directly to their cellphone on demand. This saves a lot of time in checking data and ensures that maintenance visits are only made when really required.
  • Reliability is ensured by extensive testing during production – all units are 100% tested – with particular attention to ingress and lightning protection. Careful electronic design has also made MERLIN extremely stable so that it does not drift and requires only an occasional functional check against a calibrated multimeter.

Everything You Need From a Remote Cathodic Protection Monitoring System

MERLIN has major economic, operational, safety and environmental benefits and has been installed on every continent, providing significant cost savings and making our customers’ operations more efficient.

Measurements

The measurement specification for the range of MERLIN monitors was drawn up with input from pipeline operating companies and independent CP consultants. It includes all the measurements conventionally taken at rectifiers, solar stations, test stations, cp posts, riser posts and pipeline sleeves.

MERLIN rectifier (including solar station) monitors have been designed to carry out the functional checks of rectifier output (voltage and current) required in order to comply with regulatory guidelines. They will quickly repay their capital cost when compared to manual monthly checks.

MERLIN rectifier monitors offer additional CP measurements (ON and OFF potentials) as well as the facility to synchronize remotely with other rectifiers on a pipeline for Close Interval or DCVG (Direct Current Voltage Gradient) survey measurements in the field. Pipe-to-soil potential measurements at the rectifier require a reference cell and relay.

MERLIN CP monitors channels are fully independent. A MERLIN CP Monitor can be configured to monitor either two pipe-to-soil inputs (the second input could be a sleeve or foreign pipe) or, if a coupon is fitted, one pipe-to-soil input and an instant OFF input. The MERLIN unit incorporates an internal relay, which is opened just before channel 2 is read.

All MERLIN CP monitors measure DC and AC voltages on each channel simultaneously. This has become extremely important as operators now recognise that induced AC on pipelines can have detrimental effects. If a coupon is fitted at the test post, channel 3 can be used to calculate the DC and AC current by measuring the voltage across a shunt of known value (Abriox can supply suitable shunts and cable assemblies). Once the shunt value and coupon surface area have been entered in the CPSM software, the data can be displayed either as the current in mA or as the current density in A/m².

Another configuration enables the DC potential of an unprotected (“native”) coupon to be monitored. By comparing this to a protected coupon (one that is electrically connected to the pipeline and therefore receives cathodic protection) the effectiveless of the CP system can be verified.

High and low alarms can be set for each measurement channel (for DC and AC values). A MERLIN unit will alarm as soon as a measurement is detected outside the acceptable “window” set by the user.

MERLIN Nitrogen Sleeve monitors allow the pipeline operator to check that the sleeve is maintaining the required pressure without undertaking a site visit. They are typically installed in remote areas inside GRP Cabinets, M28 Posts and at Sleeve Fill Points. Remotely monitoring these key points eliminates routine site visits and labour can be freed for data interpretation and follow up.

Now the pipeline operator can check that the sleeve is maintaining the required pressure without undertaking a site visit. Even if the gas is leaking, the operator can monitor the pressure drop and schedule maintenance accordingly. In this way unnecessary site visits can be avoided. The MERLIN measures the sleeve pressure automatically, checks that it is within specification and reports immediately if an alarm threshold is exceeded.

In addition to monitoring the gas pressure in the sleeve, the voltage of the batteries powering the sensor is also monitored and data is seamlessly sent in a management report to the system HQ where it is displayed and archived in Abriox’s MERLIN CPSM software or online via iCPSM.

Communications

MERLIN DX/GX monitors use SMS (text) messaging over the cellular network to report data from the field to a central HQ.  SMS communication enables MERLIN monitors to be set up in the field using a cell/mobile phone. MERLIN monitors incorporate an internal antenna which, in most locations, will be quite adequate. In weak signal areas, units can be equipped with an external antenna (model dependant).  This method has several advantages:

  • Massive investment in infrastructure by network providers
  • 90% coverage in most countries
  • Excellent coverage in virtually all urban and semi-urban locations
  • Expanding coverage worldwide into remote/rural areas

  • Proven reliability

  • Low cost

The MERLIN system is independent of network provider and Abriox will work with users to secure the most advantageous communication package in their country.

For areas of the world where there is no celluar network coverage, the MERLIN XT Transformer Rectifier Monitor offers 100% global satellite communication. Abriox selected the Iridium system for its high performance and high integrity. Among its many advantages over other satellite systems are:

  • Global coverage

  • Compact antenna

  • No satellite antenna alignment concerns

  • Low power consumption

  • Large data packets

  • Low, uniform, message latency

The last point there is very important - some satellite systems can take up to an hour to send/receive a message if the system is busy, Iridium is 20 sec to 2 minutes (maximum). This is because the Iridium meshed constellation relays data from satellite to satellite without touching ground until it is downlinked at an Iridium gateway. This means the MERLIN XT can be very quickly installed with negligible waiting time – a huge advantage to our customers.

Built-in Lightning Protection

Pipelines are a significant attractor for lightning, and in some regions of the world strikes can occur frequently. Abriox has always designed lightning protection into our MERLIN monitors.

To improve the MERLIN protection further, Abriox worked with Cobham Technical Services, one of the world’s leading specialists in lightning testing and consultancy.

As a result of the work with Cobham, MERLIN’s protection against high energy surges has been substantially enhanced through electronic design (surge protection circuitry, more resilient components and a revised physical layout) and the identification of new surge arrestors with improved performance.

High Energy Surges

As a result of the work with Cobham, MERLIN’s protection against high energy surges has been substantially enhanced through electronic design (surge protection circuitry, more resilient components and a revised physical layout) and the identification of new surge arrestors with improved performance.

Remote Synchronized Interruption

This feature (available on Super and Excel models) enables rectifiers on the same pipeline to synchronize their output and interrupt it according to a precise timing interval.

The on-board GPS module enables precise time synchronization of all MERLIN monitors on a pipeline. It also provides a link to mapping software for accurate positioning. Compatible with all industry recognised Close Interval and DCVG survey patterns and most portable above-ground survey equipment.

Interruption may be switched on and off, or the cycle changed, from a cell/mobile phone in the field (DX/GX versions only), from the CPSM software or online via iCPSM.

Pipeline Locate

This unique feature is particularly useful for gas and petrochemical companies who have a lot of CP installations. The “pipeline locate” signal can be activated from the system software in the office – or from a mobile phone in the field using text messaging.

Used in conjunction with a MERLIN Interrupter, it can switch or modulate the rectifier’s output current to generate an electromagnetic “pipeline locate” signal that can be traced and pin-pointed using a pipe/cable locator. It completely eliminates the laborious set-up time associated with traditional pipeline location equipment – and ensures the locate signal is applied to the correct pipeline!”

The feature is patented and is available on MERLIN EXCEL transformer rectifier monitors.

AC Monitoring

It is now recognised that cathodically-protected pipelines (and other metal structures) may be affected by AC from nearby power lines or traction systems.

This phenomenon is thought to be of particular concern in the case of pipelines with high quality (eg fusion-bonded epoxy) coatings that run parallel to high-voltage overhead transmission lines. There is also evidence to suggest that AC-assisted corrosion can occur below the 15VAC threshold.

The MERLIN system has been designed to enable pipeline operators to monitor levels of AC on their pipeline – and to monitor their effect (if any) on the cathodic protection system. The MERLIN CP Monitor measures simultaneous DC and AC levels on all channels.

AC Corrosion

Abriox’s MERLIN system has been designed to enable pipeline operators to monitor levels of AC on their pipeline – and to monitor their effect (if any) on the cathodic protection system. The MERLIN CP Monitor measures simultaneous DC and AC levels on all channels.

Powerful Software. Say Hello to CPSM!

Pure Innovation

Data from MERLIN Monitors is automatically stored and transmitted in a management report to the system HQ where it is displayed and archived in the MERLIN CPSM software (Desktop application) or accessed on-line via the internet based iCPSM.

iCPSM (Internet-based Cathodic Protection System Manager)

iCPSM

iCPSM (Internet-based Cathodic Protection System Manager) - Online database software package for displaying, archiving and exporting data from MERLIN monitors.

CPSM (Cathodic Protection System Manager)

CPSM

CPSM (Cathodic Protection System Manager) - PC based database software package for displaying, archiving and exporting data from MERLIN monitors.

Monitors can be configured to send their data to two HQs; changes made at one HQ are automatically updated at the other HQ with a full audit trail of all changes made to the system.  User access levels (Controller, Technician, Viewer) are allocated via the system licence to ensure that the appropriate features are available to authorised personnel.

CONTACT US FOR MORE INFORMATION ON HOW ABRIOX REMOTE MONITORING SYSTEMS CAN IMPROVE YOUR NETWORK MANAGEMENT

The most cost-effective, completely wireless remote monitoring system for the oil, gas, petrochemical pipeline protection industries.

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View the MERLIN Range

We believe MERLIN to be the most comprehensive CP monitoring system available, providing unrivalled performance and reliability and making it the system of choice for CP professionals.

Rectifier and Solar Station Monitors

Rectifier and Solar Station Monitors

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Test Post and Bond Monitors

Test Post and Bond Monitors

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Nitrogen Sleeve Monitors

Nitrogen Sleeve Monitors

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Interrupters

Interrupters

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Database Software

Database Software

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