Bender Renewable Energy

G Insulation monitoring

G Insulation monitoring devices (ISOMETER®) in practice – greater information advantage In unearthed systems Insulation monitoring in main circuits Insulation monitoring in auxiliary and control circuits Unearthed power supplies (IT systems) have an invaluable advantage in that a first fault will not cause a failure. As a result complex processes and the operation of the wind energy plants are not interrupted. Quite the contrary, IT systems can continue to operate under controlled conditions and faults can be rectified at an appropriate stage, without incurring the costs associated with failures. IT systems differ from each other in terms of the voltage level, the natural insulation resistance, the amount of leakage capacitances and the voltage waveform (AC, DC, AC and DC components, etc.). The requirements on insulation monitoring result from these characteristics. What should you do? ■■ Select the IT system ■■ Use an appropriate insulation monitoring device (ISOMETER®) ■■ Permanently monitor the entire insulation resistance Your benefits ■■ Highest possible availability of the installation, as the first insulation fault does not result in shutdown ■■ Higher, more reliable earthing resistance ■■ Due to low fault currents, no risk of fire ■■ More flexibility during maintenance ■■ Improved electromagnetic compatibility ■■ decisive information advantage 4 Pitch-Control M M UPS M 4 RCMS460 G M Yaw 3 Ethernet Control 2 ISOMETER ® 1 BMS Bus ISOMETER ® IR425 COM460IP Voltage and Frequency Monitor VMD460 6 5 SCADA Router 1. Insulation monitoring No operational interruption on the occurrence of a first insulation fault. Insulation monitoring device ISOMETER® iso685 2. Control errors and failures of control and display equipment are avoided. Insulation monitoring device ISOMETER® IR425 3. AC/DC sensitive residual current monitoring Unexpected shutdowns in safety-critical systems and standstill of the wind energy plant can be prevented Multi-channel AC, pulsed DC and universal AC/DC sensitive residual current monitoring system RCMS460 4. Makes it possible to detect a gradual insulation degradation, e.g. by means of W35AB measuring current transformers 5. Monitoring of electricity generation systems Monitoring of phase sequence, frequency and voltage with threshold parameters that can be configured. Voltage and frequency monitoring relay VMD460 6. Communication Gateways make it possible to transmit the insulation resistance and the residual currents to monitoring systems. BMS Ethernet gateway COM460IP

G High availability of large photovoltaic systems Increased performance without additional effort While during the planning of a photovoltaic system the implementation of the project with the lowest possible costs is in the foreground, during the operation of the completed system the focus is on the revenue. Failures are to be avoided at all costs. The investment costs for suitable insulation monitoring are already amortised on the occurrence of the first insulation fault. ISOMETER® isoPV Why unearthed photovoltaic systems? ■■ ■■ ■■ ■■ ■■ ■■ ■■ ■■ ■■ No operational interruption on the occurrence of a first insulation fault Increased fire protection Early detection and signalling of developing insulation faults Enhanced personal safety The PV system is kept at a high level of availability Insulation fault location during operation of the photovoltaic system Costs for time and personnel can be drastically reduced Localising insulation faults all the way to the photovoltaic module Allows a distinction to be made between resistive and capacitive components Where, nevertheless, a TN system has been chosen in preference to the more reliable and stable IT system, in many industrial sectors this is due to the high investment costs associated with the required transformer. For photovoltaic plants in the MVA range, however, the galvanic isolation in form of a medium voltage transformer, that is required for the IT system, is already realised. An unearthed system with suitable monitoring according to DIN VDE 0100-410 is ideally suited for this purpose. The device series is optimised for low insulation values and high system leakage capacitances in large-scale plants. It is not without reason that the isoPV series Bender ISOMETER® was voted the Best Product of Contest at the international tradefair for the electrical and electronics industry ELECRAMA 2012. The isoPV monitors photovoltaics systems with outputs up to several MVA safely and reliably. GUARANTEED ELECTRICAL SAFETY IT system MV system PV Array PV Generator DC IT-System 0...1100 V Inverter without transformer Trafoloser Wechselrichter R f DC+ ISOMETER® isoPV C e < 2000uF R f DC- AGH-PV Voralarm/Alarm Typical design of an unearthed photovoltaic system in the MVA power range 5