Basic Energy Metering. TYPES OF METERS AND ITS Testing. Meter Tampering

Transcription

1 Basic Energy Metering TYPES OF METERS AND ITS Testing Meter Tampering BRAJANATH DEY (Meter Testing Laboratory) TATA Power - DDL 23 rd Nov. 2017

2 What is Energy METER? An electricity energy meter is a device that measures the amount of ELECTRIC ENERGY consumed by any premises. Energy meter operates by continuous measuring of the instantaneous electrical parameters like VOLTAGE, CURRENT, PF, Frequency etc. and calculate them to give instantaneous ELECTRIC POWER which is then INTEGRATED against time to give an ENERGY consumption. Energy meters are typically calibrated in term of billing units that is most commonly known as kilowatt hour. kwh is equal to theamount of energy consumed by a load of one kilowatt over a period of one hour that is equal to 1000 watt or 3,600,000 joules or 01 unit or 01 kwh P = V I Cosθ ; E = V I Cosθ. t

3 Block Diagram of Electronic Energy Meter Memory Current Sensor Multi plier ADC Micro Controller DISPLAY Voltage Sensor RTC Analog to digital converter Optical Port Push Button

4 Review of fundamental electrical concepts Active Energy (unit kwh) V X I X Cos θ Reactive Energy (unit kvarh) V X I X Sinθ Apparent Energy (unit kvah) V X I Where, V is line volt, Single Phase Vp X Ip X cos θ Three Phase 3 Phase 4 Wire 3 x Vp X Ip X cos θ 3 Phase 3 Wire 3 x VL X IL X cos θ I is line current, θ is phase angle between volt and current, Cos θ is power factor

5 Methods of Sensing of Voltage & Current for Energy Measurement

6 Single Phase Electronic Whole Current Meters Shunt Circuit (Voltage Coil)/CT Circuit (Current Coil) Meter without CT

7 3-Ph, 4-Wire CT Unit & Meter / Whole Current Meter Outgoing Terminals Resin Cast CT Unit Meter Display Optical Port Calibration LED Modem Name Plate Incoming Terminals Terminal Block

8 CT Unit CT & PT Pins Outing Terminals Modem Connection CT Ratio Incoming Terminals 8

9 Indoor type HT Metering Cubicle with inbuilt resin cast CT & PT Control Cables CT PT Unit

10 Outdoor type HT Metering Cubicle with CT PT Unit

11 WHY ELECTRONIC METERS??? SPECIFICATION STATIC METERS CONVENTIONAL ELECTRO- MECHANICAL METERS Life Sustainable accuracy life-over 5 years Limited life Wear & Tear No wear & tear Lot of wear & tear Meter becomes slow with time Hanging of Meter Measures accurately under any conditions. Accuracy is effected with change in angle of hanging Protection Fully protected in case of wrong connection Get damaged with wrong connections Tampered Measures accurately in various Tampered conditions - Reverse Tamper - Earth Tamper - Immune to DC influence - Distributed phase sequence Meters either do not records in tampered conditions or even start running in reverse condition Power Loss in voltage Circuit is continuous & is unmetered Loss in Voltage Circuit of Electronic meter is low Loss in Voltage circuit of Conventional Meters is high

12 Types of meters & Ratings of Energy Meters

13 Ranges, Rating & Accuracy Class Type of Meter Installed Class Rating of Conventional Meters Installed Applied Load Factor Single phase A Up to 10 Kw Three Phase A Kw CT Operated 0.5s 100/5 A 200/5 A Kw Kw HT Meter 0.5s Above 100 KW

14 Tests Conducted on Energy Meters Type Tests All tests as defined in relevant IS Test against abnormal magnetic influence as per CBIP TR 325 DC immunity test (injection both on phase and neutral terminal) Test for Material used for Terminal Block and meter body as per relevant standards IP test Routine Tests AC High Voltage test Insulation test Test on limits of error Test of starting current Test of no load condition Special Test ESD JAMMER Magnet Temperature rise of terminal block with 120% Imax for 6 hours Overload test at 150% of Imax for accuracy

15 Tests Conducted on Energy Meters Acceptance Test AC High Voltage test Insulation test Test on limits of error with following loads Test of meter constant Test of starting current Test of no load condition Test of repeatability of error. Test of power consumption. Test for Immunity against external influencing signal as per the TATA POWER-DDL specification Test for Immunity against DC Immunity as per the TATA POWER-DDL specification Test for Immunity against Tamper conditions 38 tampers as per the TATA POWER-DDL specification Error measurements with all abnormal condition along with ESD and magnet Test to Influence of Harmonics Supply voltage and frequency variation test Testing of self-diagnostic features All tamper tests, count increment and logging with date and time 120% I max(120a) I max (100A) Ib(20A) 0.5 Ib (10A) 0.1Ib (2A) 0.05Ib (1A) UPF, 0.8 lead and 0.5 lag UPF, 0.8 lead and 0.5 lag UPF, 0.8 lead and 0.5 lag UPF, 0.8 lead and 0.5 lag UPF, 0.8 Lead and 0.5 lag UPF

16 Different types of meters & Modems

17 Type of Energy Meters 1-ph, 2 Wire Meter Whole Current Meter 3-ph, 4-Wire Whole Current Meter 3-ph, 4-Wire CT Operated Meter 3-ph, 3- Wire HT Meter Pre-Paid Meter Post Paid Meter DT Meter Feeder Meter Consumer Meter 3-ph, 4-Wire HT Meter Smart Meter Net Meter

18 Evaluation of Single Phase Whole Current Electronic or Static Energy Meters Semi-digital Liquid Crystal Display (LCD) Latest Postpaid Meters Pre-paid metering

19 Meter Reading Instruments & Modems Used in TPDDL DMRI Modem CMRI

20 Components Used for AMR & Individual Meter Vendor Software Static Energy Meter with data transfer capabilities MODEM TRANSMISSION MEDIUM Software & Systems for data Collection and processing BCS L&T SECURE ABB L&T SECURE ABB GSM Modem GSM Modem GSM Modem

21 Dishonest Abstraction of Energy (DAE) Theft by meter tampering and its detection

22 DAE and its detection Tampering of meters by: Tilting of meters physically Creating small pin hole in the meter body Inserting of thin strip/film to stop the disc Use of magnets / magnetic sensors Deliberately inserting shunt wire between incoming and outgoing meter terminals Inserting Switch in Neutral circuit By interchanging the I/C phase and neutral High Voltage High Frequency (HVHF) injection in the neutral circuit by using oscillator/spark plugs Using external resistors inside PCB of Meter Bye Passing of Meter through Remote control Device or CT Secondary Ckt.

23 Physical Tampering Double Shunt SHUNTS IMPLANTED AT THE REAR OF SP STATIC METER PHYSICAL TAMPERING IN SINGLE PHASE METERS BY INSERTING SHUNT WIRE

24 Physical Tampering Single Shunt SINGLE SHUNT NEUTRAL WIRE OF METER REMOVED AND EARTHED PHYSICAL TAMPERING IN SINGLE PHASE METERS BY INSERTING SHUNT WIRE

25 Physical Tampering IN SINGLE SHUNT CASES, NEUTRAL IS GROUNDED VIA A TWO WAY SWITCH PHYSICAL TAMPERING IN SINGLE PHASE METERS BY EARTHING THE NEUTRAL WIRE

26 Physical Tampering Resistors with PCB EXTERNAL RESISTORS IN METER PCB CIRCUIT PHYSICAL TAMPERING IN SINGLE PHASE METERS BY INSERTING EXTERNAL RESISTORS

27 Physical Tampering Re-Soldering on PCB RESISTOR REMOVED AND RE-FIXED; RE-SET SOLDER MARKS PHYSICAL TAMPERING IN SINGLE PHASE & THREE PHASE METERS BY RE-SOLDERING ON PCB

28 Physical Tampering MAGNETIC PROXIMITY SENSOR SWITCH WAS DETECTED. A MAGNETIC PROXIMITY SWITCH IS A DEVICE WHICH SWITCHES ON IN THE PRESENCE OF A MAGNET. IN THIS CASE, THE SWITCH WAS DISCONNECTING THE POWER SUPPLY TO THE METER CIRCUIT TAMPERING IN SINGLE PHASE METERS BY INSERTING MAGNETIC SENSOR

29 Physical Tampering Hole on Meter Body HOLES ON DIFFERENT PARTS OF THE METER BODY PHYSICAL TAMPERING IN SINGLE PHASE METERS BY CREATING HOLE ON METER BODY

30 Physical Tampering Remote Circuit on PCB REMOTE CIRCUIT ON METER PCB & EL LED DISTURBED PHYSICAL TAMPERING IN SINGLE PHASE METERS BY INSERTING REMOTE CIRCUIT ON PCB

31 Dishonest Abstraction of Energy (DAE) METER DATA TAMPERING

32 ESD / Jammer Tampering TAMPERING IN THREE PHASE METERS BY JAMMER CIRCUIT

33 ESD / Jammer Tampering Power failure due to Remote/Jammer No power failure logged in same source data TAMPERING IN THREE PHASE METERS BY JAMMER CIRCUIT

34 Time Of Day (TOD) Feature Capable of measuring Cumulative Energy in kwh, kvarh & kvah and Maximum Demand in kw & kva with time of day (TOD) registers having profiles 6 Zones however at present 3 zones are provided i.e. Off Peak, Normal & Peak MD Integration Load Survey Seasons Month Off Peak (T0) Normal (T1) Peak (T2) Season- 1 Season -2 April- September (Summer) October- march (Winter) hrs hrs hrs hrs hrs hrs

35 Metering Standard: IS13779:1999: AC Static Watthour Meters, Class 1.0 and 2.0 IS14697:1999: AC Static Transformer operated Watthour and VAR hour meters, Class 0.2 and 0.5 IS16444:2015: AC Static Direct Connected Watthour Smart Meter Class 1 & 2 Specification IS15884:2010: AC direct connected static Prepayment Meter for active Energy CBIP-88/304/325: CBIP specification of ac Static Electricity Energy Meter IS15959:2011: Data exchange for electricity meter reading, tariff and load controlcompanion specification IS12346: Testing Equipment for AC Electrical Energy Meters IS15707: Testing, Evaluation, installation and maintenance

36