Bender UK technology enhances subsea cable monitoring capabilities
15 November 2018
The market proven subsea line insulation monitor (LIM) from Bender achieves even greater performance when used with a Bender coupling device, detecting up to 10GΩ and monitoring IT systems up to 1,760V DC and 12 kV AC.
Subsea umbilical monitoring and ROV applications are primary applications for Bender ISOMETER® isoHR685W LIM which is designed to monitor, report and provide early warning of subsea cable insulation degradation and failure, enabling preventative maintenance and reducing unplanned shutdowns.
Interference from neighbouring monitoring devices in capacitively coupled IT systems is suppressed and filtered out by Bender’s advanced ‘ISOsync’ feature that enables multiple LIMs to be fitted across the umbilical power cores. A measuring range of up to 10 GΩ allows the trend of the insulation level to be recognised at an early stage.
The isoHR685W uses the extended Adapted Measuring Principle [AMP] to overcome limitations of DC measuring signals by superimposing a clocked, pulsed measuring voltage onto the system. The microprocessor-controlled signal automatically adapts to system conditions such as high leakage capacitances.
The subsea LIM uses proven technology and is compliant to IEC 61557-8. It is universally applicable in AC, 3(N)AC, AC/DC and DC systems. AC systems may include extensive DC-supplied loads (such as rectifiers, inverters, variable speed drives). It can be used to monitor IT AC systems with galvanically connected rectifiers or inverters and for IT DC systems (IT = unearthed systems). It is designed to automatically adapt to the existing system leakage capacitance and incorporates automatic self-testing of the device.
The device can be set remotely and monitored worldwide for remote diagnosis via cloud-based technology. It is also possible to operate several LIMs in coupled IT systems when connected via an Ethernet bus. The integrated ISOnet function ensures that only one LIM is actively measuring at a time, while the other devices are isolated from the system, waiting in standby mode for measuring permission. The ability of the device to synchronise with others makes it possible to monitor capacitive coupled IT systems without interfering with each other.
Bender UK has significant experience in the oil and gas sector, delivering solutions such as earth fault location and insulation monitoring technology which monitors and predicts developing insulation failures in North Sea fixed and mobile platforms, as well as subsea applications.
The technical team at Bender UK offers project design support, offshore installation, commissioning, fail diagnosis and through life technical support.