V I S H AY I N T E R T E C H N O L O G Y, I N C . ESTAsym W Vishay ESTA ESTAsym W Unbalance Monitoring APPLICATION When a short circuit occurs in the winding element of a capacitor unit, gas can form, causing the capacitor case to swell and eventually burst if left uncontrolled. A protection relay can be used to detect such faults well in advance. The relay compares the star points of two parallel star connected capacitor arrangements. As soon as there is a voltage shift in one of the star points, an unbalanced current will flow between the two star points. The protection relay can be configured to indicate the fault and disconnect the faulty capacitors when this tripping current goes over a predetermined value. Capacitor banks arranged in a bridge circuit can also be controlled by the ESTAsym W, which in such cases is connected in the midpoint of the bridge (Fig. 2). The combination of an ESTAsym W and ESTAsym Relay can recognize winding element failure early on and disconnect the capacitor bank before any significant damage occurs. RESOURCES • For technical questions contact [email protected] A WORLD OF SOLUTIONS PRODUCT OVERVIEW 1/4 THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000 VMN-PL0454-1602 www.vishay.com V I S H AY I N T E R T E C H N O L O G Y, I N C . ESTAsym W Vishay ESTA Setting of Tripping Value The choice of the appropriate tripping value for the unbalanced current depends on how the capacitors are connected internally and upon the external arrangement of the capacitor bank. Factory recommendations for alarm and/or tripping values as well as time delays are included in the contractual documentation supplied with each capacitor bank at time of delivery. L1 L2 L3 C4 C5 C6 C1 C2 C3 ESTAsym W Relay Fig. 1 Double star connection L1 L2 ESTAsym W ESTAsym W Relay ESTAsym W L3 Fig. 2 Bridge connection Factory Tests Because the ESTAsym W is intended exclusively to protect capacitor banks, we use the testing voltages specified by the IEC 60871 standard for capacitors in performing our insulation test for the ESTAsym W. This means that on the basis of insulation class 12 kV or 17.5 kV the primary sides are tested to the secondary side/housing with 28 kV AC/10 s or 38 kV AC/10 s respectively. The test of the secondary side to the housing is made with a voltage of 2.5 kV AC for 10 s. Testing the ESTAsym W for Proper Functioning For reliable operation, we recommend a regular examination of the complete capacitor protection set-up. The operation of the alarm and trip levels for the protection circuits are best confirmed though primary current injection of the ESTAsym W. Following an alarm or trip operation, the capacitor bank should only be re-energized after it has been thoroughly inspected. PRODUCT OVERVIEW 2/4 THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000 VMN-PL0454-1602 www.vishay.com V I S H AY I N T E R T E C H N O L O G Y, I N C . ESTAsym W Vishay ESTA Rated Primary Current: Maximum Overload: Installation: 5 A – 10 A – 25 A – 50 A 200 A / 1 s Rated Secondary Current: Frequency: Available for indoor (Fig. 3) and outdoor (Fig. 4) mounting 1A 50 Hz / 60Hz Accuracy Class: Temperature: Class 1 - 30 °C / 65 °C VA-Rating: Insulation Level: 1.5 VA 12 kV (28 kV / 75 kV) 17.5 kV (38 kV / 95 kV) Protection Level: Protection level IP00, specially designed to fit capacitor bank assemblies with IP55 terminal cover Fig. 3 Indoor type with bushing D-199 Fig. 4 Outdoor type with bushing D-401 PRODUCT OVERVIEW 3/4 THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000 VMN-PL0454-1602 www.vishay.com V I S H AY I N T E R T E C H N O L O G Y, I N C . ESTAsym W Vishay ESTA SEMICONDUCTORS MOSFETs Segment MOSFETs Low-Voltage TrenchFET® Power MOSFETs Medium-Voltage Power MOSFETs High-Voltage Planar MOSFETs High-Voltage Superjunction MOSFETs Automotive-Grade MOSFETs ICs VRPower® DrMOS Integrated Power Stages Power Management and Power Control ICs Smart Load Switches Analog Switches and Multiplexers Diodes Segment Rectifiers Schottky Rectifiers Ultra-Fast Recovery Rectifiers Standard and Fast Recovery Rectifiers High-Power Rectifiers/Diodes Bridge Rectifiers Small-Signal Diodes Schottky and Switching Diodes Zener Diodes RF PIN Diodes Protection Diodes TVS Diodes or TRANSZORB® (unidirectional, bidirectional) ESD Protection Diodes (including arrays) Thyristors/SCRs Phase-Control Thyristors Fast Thyristors IGBTs Field Stop Trench Punch-Through Trench Power Modules Input Modules (diodes and thyristors) Output and Switching Modules (contain MOSFETs, IGBTs, and diodes) Custom Modules PRODUCT OVERVIEW Optoelectronic Components Segment Infrared Emitters and Detectors Optical Sensors Proximity Ambient light Light Index (RGBW, UV, IR) Humidity Quadrant Sensors Transmissive Reflective Infrared Remote Control Receivers Optocouplers Phototransistor, Photodarlington Linear Phototriac High-Speed IGBT and MOSFET Driver Solid-State Relays LEDs and 7-Segment Displays Infrared Data Transceiver Modules Custom Products PASSIVE COMPONENTS Resistors and Inductors Segment Film Resistors Metal Film Resistors Thin Film Resistors Thick Film Resistors Power Thick Film Resistors Metal Oxide Film Resistors Carbon Film Resistors Wirewound Resistors Vitreous, Cemented, and Housed Resistors Braking and Neutral Grounding Resistors Custom Load Banks Power Metal Strip® Resistors Battery Management Shunts Crowbar and Steel Blade Resistors Thermo Fuses Chip Fuses Pyrotechnic Initiators / Igniters Variable Resistors Cermet Variable Resistors Wirewound Variable Resistors Conductive Plastic Variable Resistors Contactless Potentiometers Hall Effect Position Sensors Precision Magnetic Encoders Networks/Arrays Non-Linear Resistors NTC Thermistors PTC Thermistors Thin Film RTDs Varistors Magnetics Inductors Wireless Charging Coils Planar Devices Transformers Custom Magnetics Connectors Capacitors Segment Tantalum Capacitors Molded Chip Tantalum Capacitors Molded Chip Polymer Tantalum Capacitors Coated Chip Tantalum Capacitors Solid Through-Hole Tantalum Capacitors Wet Tantalum Capacitors Ceramic Capacitors Multilayer Chip Capacitors Disc Capacitors Multilayer Chip RF Capacitors Chip Antennas Thin Film Capacitors Film Capacitors Power Capacitors Heavy-Current Capacitors Aluminum Electrolytic Capacitors ENYCAP™ Energy Storage Capacitors 4/4 THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000 VMN-PL0454-1602 www.vishay.com