Transformer Protection and Control RET615 Brochure - ABB Oy Distribution Automation - (Version JPG) - PDF Catalogue | Technical Documentation



	Transformer Protection and Control RET615 Relion® 615 series

RET615 is a dedicated transformer protection and control

IED for power transformers, unit and step-up transformers including power generator-transformer blocks in utility and industry power distribution systems. RET615 is a member of ABB's Relion® product family and a part of its 615 protection and control product series. The 615 series lEDs are characterized by their compactness and withdrawable design. Re-engineered from the ground up, the 615 series has been designed to unleash the full potential of the IEC 61850 standard for communication and interoperability between substation automation devices.

Application RET615 is the ultimate protection and control IED for two-winding power transformers and power generator-transformer blocks. RET615 is available in four standard configurations to match the most commonly employed power transformer vector groups and to coordinate the applied transformer neutral earthing principles with the relevant earth-fault protection schemes. Protection and control RET615 features, three-phase, multi-slope transformer differential protection with an instantaneous stage and a stabilized (biased) stage to provide fast and selective protection for phase-to-phase, winding interturn and bushing flash-over faults. Besides second harmonic restraint an advanced waveform-based blocking algorithm ensures stability at transformer energization and a fifth harmonic restraint function ensures good protection stability at moderate overexcitation of power transformers. Sensitive restricted earth-fault protection (REF) completes the overall differential protection to detect even single phase-to-earth faults close to the neutral earthing point of the transformer. Either the conventional high-impedance scheme or a numerical low-impedance scheme can be selected for protection of the windings. When the low-impedance REF protection is used neither stabilizing resistors nor varistors are needed and as a further benefit the transforming ratio of the neutral earthing CTs can differ from those of the phase		current transformers. Due to its unit protection character and absolute selectivity the REF protection does not need time grading with other protection schemes, and therefore highspeed fault clearance can be achieved. RET615 also incorporates a thermal overload protection function, which supervises the thermal stress of the transformer windings to prevent accelerated aging of the insulations. Multiple stages of short-circuit, phase-over-current, negative-phase-sequence and earth-fault back-up protection are provided for both high and low voltage side of the transformer. Earth-fault protection based on the measured or calculated residual overvoltage is also available. Finally, RET615 also offers circuit-breaker failure protection. Enhanced with an optional plug-in card, RET615 offers a fast three-channel arc-fault protection system for arc flash supervision of the switchgear compartments. RET615 also integrates basic control functionality, which facilitates the control of one circuit breaker via the front panel HMI or by means of remote controls. To protect the IED from unauthorized access and to maintain the integrity of information, the device has been provided with a four-level, role-based user authentication system. The access control system applies to the front panel HMI, the web browser based HMI and the PCM600 Protection and Control IED Manager.

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Transformer Protection and Control RET615 Brochure - ABB Oy Distribution Automation - #1

Motor protection relay, Gateway, Controller, Relay, Differential relay