For Electrical Engineering stidents in Seminar.

1. BASICS OF ENERGY
METERING
AND
FRAUD DETECTION
Presented By - ABHISEK NARAYAN
SWAIN,
B.TECH(EEE)
Regd. No.- 1301289273
Dt: 25.07.2016

2. CONTENTS
 Basics of energy meters
Types of 1-phase Energy Meters
Testing of 1-phase Energy Meter at Laboratory & Field
Types of 3-phase Energy Meters
Testing of 3-phase Energy Meters at field & Laboratory
Different Types of Tampering in Energy Meters
References

3. 1

4. Power in ac circuits....a quick recap
Power per phase is
P=VPIP cos(φ)
Power for all 3- phases is
P=3VPIP cos(φ) or
P=V1I1 cos(φ1) + V2I2 cos(φ2) + V3I3 cos(φ3)
Since for a Balanced Load Power is Constant ,So
P(t) = 3VPIP cos(φ) also
Power in terms of Line quantity
P= √3 VLIL cos(φ)
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5. TYPES OF 1-φ ENERGY METERS
1.EM induction kWh meter
2.Electronic counter/Hybrid Type 3.Electronic multifunction
kWh Meter
3

6. A TYPICAL LCD DISPLAY OF STATIC METER:-
4

7. Measurement of power in 1- φ ac circuit
Single Watt-Meter Method :-
5

8.  The routine tests carried out in the Utility’s laboratory are:
1. Long period dial test
2. Non-registration with voltage alone-creep test
3. Starting current test
 (1) The long period dial test is done with the help of R.S. S
(Reference sub-standard) meter.
 The meters are started and stopped simultaneously after
connecting to the same load for a fixed period of say half
an hour.
 Then,
 Percent error = (R – A )/R x 100
 R = Energy recorded by kWh meter under test
 A = R. S.S. meter
ROUTINE TESTS:-
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9. 1-φ Energy Meter Testing at Laboratory
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10. 1-phase Meter Testing at site:-
 Apart from testing and calibrating the meters, they must be
properly installed, as per the connection diagram.
 After installation of meter, its performance should be checked
at site also.
 Let us take 100 watt lamp (resistive load and time constant of
energy meter is 2400 rev. /kWh.
 Assuming normal supply voltage, the consumption in one hour
will be 100 watt hours. The meter disc should therefore rotate
 (a) (2400 x 100)/1000 = 240rev./hour.
 Therefore, time taken for one revolution is
 (60 x 60)/240 = 15 seconds.
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11. TYPES OF 3-φ ENERGY METERS:-
1. Whole Current Meter
2. LT CT Operated Meter
3. HT Meter
9

12. 3-Phase Meter Testing at Site:-
 All the meter details (sl. No., rating etc.) re noted down to
know whether the capacity of the installed meter is suitable
for the connected load of the consumer.
 Meter reading is taken starting from date , time and all
parameters including instantaneous parameters, tamper
data etc. From these data the present status of the meter is
ascertained.
 Further Meter reading instrument(MRI) is connected to the
communication port of the meter. The reference standard
(Standard Meter) is connected in series with the meter to
find out the accuracy of the meter. With the help of clamp
meter the current & voltage of all phases at the meter
terminal is compared with the MRI data & meter display
data. Subsequently from these data the instantaneous load
drawn by the consumer is measured & compared. In case of
consumer owned transformer the load of the transformer
secondary side is checked and compared with that of the
meter to ascertain correct recording of energy. 10

13. Further Meter reading instrument (MRI) is connected to the
communication port of the meter. The reference standard
(Standard Meter) is connected in series with the meter to find
out the accuracy of the meter. With the help of clamp meter the
current & voltage of all phases at the meter terminal is compared
with the MRI data & meter display data. Subsequently from these
data the instantaneous load drawn by the consumer is measured
& compared. In case of consumer owned transformer the load of
the transformer secondary side is checked and compared with
that of the meter to ascertain correct recording of energy
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14. TAMPERING:-Any intentional action on the metering system by
consumer or his agent , So as to record the Consumption Lower than Actual.
TAMPER DETECTION AND LOGGING:-
•Meter analyses the electrical parameters and their relationships to make a
judgement whether this is a situation , which may happen due to normal load
condition or is artificially caused.
•Tamper detection logics can be as powerful as application knowledge and it’s
appropriate implementation in s/w. Some tamper detection needs special hardware
support also.
4th
current sensor and support circuit
Magnetic field detection
Meter cover open detection
12

15. Potential Link Open !
13

16. Current By Pass!
14

17. Common Tampering Method(1):-
•Open link/make it loose, on TB
or inside Meter cover
•Voltage coil/Sensor not getting
Voltage
•Meter stops ,No recording
•Consumer Continues to get
Power
•Missing Potential Tamper.
Some Common Tampering methods are given below:-
15

18. Common Tampering Method(2):-
Damage Gears
Change Gears
Disk Rotates,But Counter
doesn’t increment
proportionally
No or Less Recording
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19. Common Tampering Method(3):-
Stop the disk rotation by
blocking it, like wire, film
Sticky materials on
bearings, makes it slow,
eventually may stop.
No Recording for the
duration of Tamper
Change the counter readings by removing meter glass
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20. Common Tampering Method(4):-
Interchange in & out wire of
the meter.
Meter count will
decrement,if no reverse
stop,else stop incrementing.
Consumer continues to get
supply,but not recorded
Current reversal or CT
reverse tamper
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21. Common Tampering Method(5):-
By Pass
Strong shunt in meter to bypass most of the current
New Electronic single phase Meter
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22. Common Tampering Method(6):-
Earthed Load
2-WIRE SYSTEM
No recording for the duration of tamper
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23. References:
 MRT Laboratory, CESU,odisha.
 "Handbook for Electricity Metering" by The Edison Electric Institute
—The Bible of electricity meters, continuously updated since
electricity was discovered.
 http://tdworld.com/smart-grid/india-spend-216-billion-smart-grid-
infrastructure-2025
 “People Who Steal Edison’s electricity” Daily Yellowstone journal.
March 27, 1886. Retrieved 2016-07-09.
 http://www.prnewswire.com/news-releases/world-loses-893-billion-
to-electricity-theft-annually-587-billion-in-emerging-markets-
300006515.html
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