CATHODIC PROTECTION

TRU'S, FDU's & NDU's

KEY FEATURES

Transformer Rectifier Units for impressed-current cathodic protection
Forced Drainage Units for stray-current control
Custom AC input and DC output configurations
Adjustable and controlled DC output options
Robust transformer and rectifier construction
Electrical isolation between circuits where required
DC metering and indication
Protection and monitoring functions
Application-specific FDU configurations
Designed for continuous industrial operation
Suitable for demanding pipeline and infrastructure applications
Indoor and outdoor enclosure configurations

TYPICAL APPLICATIONS

Cathodic protection and forced drainage equipment can be used in applications including:

Oil and gas pipelines
Water pipelines and infrastructure
Buried steel pipelines
Storage tanks
Fuel storage facilities
Industrial process infrastructure
Railway and pipeline interfaces
Port and marine infrastructure
Municipal infrastructure
Other buried or exposed metallic structures susceptible to corrosion or stray-current interference
Engineered for Corrosion & Stray-Current Control

Cathodic protection provides an effective method of controlling corrosion on buried, submerged and exposed metallic structures. In impressed-current cathodic protection systems, a controlled DC current is applied to the protected structure to reduce its rate of electrochemical corrosion and extend the service life of critical infrastructure.

Electrical Manufacturing designs and manufactures Transformer Rectifier Units (TRUs) and Forced Drainage Units (FDUs) for cathodic protection and stray-current control applications. These systems are engineered for reliable operation in demanding environments, including pipeline, water, industrial and infrastructure installations.

Transformer Rectifier Units (TRU’s)

Transformer Rectifier Units convert incoming AC power into controlled DC power for impressed-current cathodic protection systems. The transformer provides the required voltage transformation and electrical isolation, while the rectifier converts the AC supply into DC output suitable for the cathodic protection circuit.

TRUs are configured to suit the required DC voltage and current output, with the design taking into consideration the characteristics of the protected structure, anode system and operating environment.

Depending on the application, TRUs can incorporate adjustable or controlled DC output, metering, protection, isolation, cooling and monitoring functions.

Forced Drainage Units (FDU’s)

Forced Drainage Units are used to control stray DC currents and their effects on buried metallic structures. Where stray currents from external DC sources - such as railway traction systems or other electrical installations - enter and leave a protected structure, they can cause accelerated corrosion at points where current leaves the structure.

An FDU provides a controlled electrical path for unwanted current to return to its source, helping to minimise the damaging effects of stray - current interference while maintaining the required cathodic protection of the structure.

FDUs can be configured according to the electrical characteristics of the installation and the requirements of the drainage system, incorporating appropriate monitoring, protection, measurement and control functions.