Test Schedule - Meter Testing
The test schedule as per the Central Electricity Authority Regulations on Installation and Operation of Meters is given below.
Table: Test Schedule
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Meter Type
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Schedule
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Single Phase LT meters
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Once in 5 years after installation
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LT three phase meters (CT operated) 20 kVA to 100 kVA
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Once in a year to be checked since these are installed for high value consumers
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|
Other LT metering systems
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Once in two years after installation
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EHT / HT meters
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Below 5 MVA - Once in a year
5 to 10 MVA - Once in six months
above 10 MVA - Once in a quarter
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The testing schedule for HT consumers should cover the whole Metering System involving CTs, PTs and Pilot Wire. Detailed ratio testing of CT, PT and control Pilot/ wires is to be completed. Testing by mobile vans/mobile cubicles through secondary injections kit and phantom loading might also be carried out through Measurement Unit. All new meters should meet the needs of Accuracy Class spelt out in Table.
Table: Requirements of Accuracy Class
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Type of Consumer
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Overall Accuracy Class
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EHT Consumers (33 kV)
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0.2
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HT Consumer (44 to 33 kV)
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0.5 or better
|
|
LT Consumer (Whole Current meters)
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1.0 or better
|
|
LT Consumers (CT operated)
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1.0 or better
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