Sensor presentation

Product Scope A Sensor is a device intended to transmit a signal corresponding to the primary current or voltage to the secondary equipment. PowerIT Sensors are typically used in MV switchgears and switches for measuring, protection and indication.

Sensors vs. Instrument Transformers . . . but not in transformers! Trends in electrical engineering Size Performance Standardisation

Sensors vs. Instrument Transformers Reason: The properties of material used Saturation Unlinear range Linear range Unlinear range Remedy: Absence of iron

Why did ABB choose Rogowski coil IEC-requirements Cost effective Low life cycle cost Size Rogowski coil What is the requirment -> it should work New technic -> Better than the old ABB started to look into new technologies in 1990 IEC: ABB involved in taking up the new standard Cost Effective: Standardisation Cost savings for end customer (user friendly) reliable Easy to make/logistics

Rogowski coil First published in1912 by Rogowski and Steinhous Uniformly wound coil with non-magnetic core Output signal is proportional to the derivate of primary current IEC 60044-8 Distribute the coil Note the missing of turn wire to eliminate disturbance

Why did ABB choose voltage dividers IEC-requirements Cost effective Safe Low life cycle cost Size Capacitive voltage divider IEC-60044-7 = Electronic voltage transformers Cost effective, if no space is forceen in the switchgear special VT’s must be used Safe = VT faults very common Size = can be integrated Resistive voltage divider

Voltage divider Resistive divider Capacitive divider IEC 60044-7 Matched resistor pair 1:10 000 divider ratio Today accuracy up to class 1 Capacitive divider Zc = 1/C 1:10 000 divider ratio Accuracy up to class 3 Small size ideal for bushings IEC 60044-7 Possible to achieve accuracy class 0.2 by using resistive divider technology

Sensors vs. Instrument Transformers Rated primary current (CT)  Ip (log) Ipr = 240 A

Sensors vs. Instrument Transformers Rated primary current range (sensor)  Ip (log) Ipr = 80 A....240 A.........…1250 A

Sensors vs. Instrument Transformers Accuracy limit factor (Kalf) c Protection class 10P CS Ip (log) CT Ipr

Sensors vs. Instrument Transformers Linearity Typical error, voltage sensor

Sensors vs. Instrument Transformers Transmitted signal level Voltage transformer (ku=1,9) Voltage sensor 1,2 - 110 V, 25 VA At free potential, must be earthed Secondary losses = I2R 12 - 1100 mV, 80 mVA Always earthed in the sensor Secondary losses negligible Current transformer (Kalf =20) Current sensor 0,25 - 100 A, 5 VA At free potential, must be earthed Secondary losses = I2R 7,5 - 3000 mV, 6 mVA At free potential Secondary losses negligible High power Low power Low signal SAFE

Sensors vs. Instrument Transformers Short-circuited secondary Voltage transformer Voltage sensor 250 M Isc Isc 25 k Isc/Acu = 160 A/mm2 Temp. 500 C Explosion within 30 s Isc = Inormal

Sensors vs. Instrument Transformers Open secondary Current transformer Current sensor Uopen Isc 0 - 10 kV Isc/Acu = 40 mA/mm2

Sensors vs. Instrument Transformers Frequency response rel CT F/Hz 10 100 1000 10 000 VS (Cap.) VS (Res.) VT CS

Sensors vs. Instrument Transformers Secondary wiring Terminal blocks Instr. transf. IED Wiring and screw connections Testing of connections Sensor IED Integrated cable and connector

Secondary cabling of sensors IED S1 S2

Sensors vs. Instrument Transformers Compactness Current transformer Combi Sensor Voltage transformer Small size of active parts Only one core

Sensor Technology - CT/VT vs. Sensors Signal 1/5A / 100/110 V 150mV / 2V Secondary cables Excluded Incl. and tested Linearity No Yes Saturation Yes No Ferroresonance Yes (VT) No Temperature coefficient No Incl. in accuracy EMC No Shielded Short-circuited secondary Destructive (VT) Safe Open secondary Destructive (CT) Safe Weight 40-60 kg (CT + VT) 2-25 kg (Combi) Standardisation possible No Yes

Standards for Sensors Voltage Sensors: IEC 60044-7 (1999-12) Sensors from ABB are designed, manufactured and tested according to international standards when applicable. Voltage Sensors: IEC 60044-7 (1999-12) Instrument transformers – Part 7: Electronic voltage transformers Current Sensors: IEC 60044-8 (2002-07) Instrument transformers – Part 8: Electrical current transducers Combi Sensors: IEC 60044-3 (1980-01) Instrument transformers – Part 3: Combined transformers

Sensor, type KEVCD_ Current Sensor or Combi Sensor Measurement and protection by one sensor Dimensions and primary connections same as DIN-type CTs (DIN 42600) 12, 17.5, 24 kV, two types: A. </= 1250 A B. > 1250 A (max. 3200 A) Including coupling electrode for voltage indication

Selection Guide for KEVCD type Sensors Nominal voltage Rated current range (first row) Functions included (second row) < 1250 A 1600...3200 A I + U + Uind I + Uind I + U + Uind I + Uind Upto 12 kV KEVCD 12 AE3 KEVCD 12 AG3 KEVCD 12 BE2 KEVCD 12 BG2 Upto 17.5 kV KEVCD 17.5 AE3 KEVCD 17.5 AG3 KEVCD 17.5 BE2 KEVCD 17.5 BG2 Upto 24 kV KEVCD 24 AE3 KEVCD 24 AG3 KEVCD 24 BE2 KEVCD 24 BG2

Technical Information in KEVCD Sensor KEVCD 12 AE3 I-sensor Ipn: 1250 A Ipr (to be advised), options: 80 A (Ir of switchgear: 80-160 A) 240 A (Ir of switchgear: 160-480 A), with adapter 640 A (Ir of switchgear: 480-1250 A), with adapter Output signal: 150 mV (50 Hz), 180 mV (60 Hz) Accuracy: Class 1* / 3 (*with correction factor) U-sensor Division ratio: 10.000/1 Accuracy: Class 1/3P Ith / Idyn: 40 kA, 3s / 100 kA Insulation level: 12/28/75 kV Frequency: 50/60 Hz With ribs on top Secondary cable (length to be advised), options: 5 m, 6.5 m or 7.5 m Primary polarity (to be advised), options: Normal or reversed Coupling electrode for voltage indication included

Sensor concept

Sensors in use around the world In use in 56 countries More than 20 000 sensors in operation

Sensors in use around the world

Arguments for Sensors Safety Short delivery time Smart integration