Helena Snyman - Technical Manager and Sydney Bhengu - Customer Support Technologist Elster Kent Metering (Pty) Ltd. South Africa

Electricity meter installation and installation verification Safety NRS 057:2005 (Overview) Connections Common Mistakes Tools to verify meter installations Quadrants Vector Diagrams

Safety Apply appropriate personal protective equipment (PPE) and follow safe electrical work practices according to national regulatory practices of OCCUPATIONAL HEALTH AND SAFETY ACT, 1993 (ACT NO. 85 OF 1993) and NRS 057-4:2001. Only qualified electrical workers should install this equipment. NEVER work alone.

Safety NEVER work on a live panel. Turn off all power supplying the power meter. Always use a properly rated voltage sensing device to confirm that all power is off. Before closing all covers and doors, carefully inspect the work area for tools and objects that may have been left inside the equipment.

Safety Use caution while removing or installing panels so that they do not extend into the energized bus; avoid handling the panels, which could cause personal injury. The successful operation of this equipment depends upon proper handling, installation, and operation.

Safety NEVER bypass external fusing. NEVER short the secondary of a PT. NEVER open circuit a CT; use a shorting block to short circuit the leads of the CT before removing the connection from the power meter. The power meter should be installed in a suitable electrical enclosure. Failure to follow this instruction will result in death or serious injury

NRS 057:2005 Code of practice for electricity metering 4 Requirements of metering installations 4.1 Equipment standards 4.2 Metering system 4.3 General requirements 4.4 Requirements of metering equipment 4.5 Metering installation design 4.6 Metering equipment installation

NRS 057:2005 Code of practice for electricity metering 4.7 Compliance of the entire metering installation 4.8 Automated meter reading (AMR) for large power users 4.9 Sealing of metering equipment 4.10 Time offset

NRS 057:2005 Code of practice for electricity metering 4.1 Equipment standards Equipment shall comply with the standards applicable when originally installed or with an alternative standard, confirmed in writing by an accredited test laboratory as being equivalent to, or better than, the specified standard.

NRS 057:2005 Code of practice for electricity metering 4.2 Metering system The metering system consists of various components each of the components has an influence on the total integrity of the installation. VT s, CT s Junction boxes, Test blocks, Meter Equipment, Ancillary meter equipment, Data validation etc.

NRS 057:2005 Code of practice for electricity metering 4.4 Requirements of metering equipment Equipment used in the metering installation shall be certified as compliant with the relevant standards and approved by the licensee. Accuracy class requirements Consists of a meter(s) and associated instrument transformers are determined by the nominal size of the load, expressed in terms of apparent power.

NRS 057:2005 Code of practice for electricity metering 4.4 Requirements of metering equipment Calibration of metering installation components (SANAS) Instrument transformers Test certificates Current transformers Voltage transformers Voltage transformer burdening

NRS 057:2005 Code of practice for electricity metering 4.4 Requirements of metering equipment Meter panel ancillary equipment Test blocks Meters General requirements Meter type testing Meter calibration Meter numbering

NRS 057:2005 Code of practice for electricity metering 4.5 Metering installation design A design report shall be prepared by the metering designer in the case of a new metering installation and in the case where an existing metering installation is modified.

NRS 057:2005 Code of practice for electricity metering 4.6 Metering equipment installation General (Training) Meter panel (enclosure) Instrument transformer earths Wiring loom Measurement of current Measurement of voltage

NRS 057:2005 Code of practice for electricity metering 4.7 Compliance of the entire metering installation Commissioning report On site verification Testing and inspection of measurement transformers

Connections Single Phase, Two Wire, Whole Current Three Phase, Four Wire, Whole Current Three Phase, Four Wire, CT Connected Three Phase, Three Wire, CT Connected Summation

LINE LOAD Connections Single Phase, Two Wire, Whole Current 1 2 3 4 A N

LINE LOAD Connections Three Phase, Four Wire, Whole Current A B C N S1 VA S2 S1 VB S2 S1 VC S2 Neutral 1 2 3 4 5 6 7 8 9 10 11 A C B A B C N

TO LOAD Connections Three Phase, Four Wire, CT Connected A B C N S1 VA S2 S1 VB S2 S1 VC S2 Neutral 1 2 3 4 5 6 7 8 9 10 11 A C B A B C N P1 S1 S2 P2 P1 S1 S2 P2 P1 S1 S2 P2

TO LOAD Connections Three Phase, Three Wire, CT Connect A B C N S1 VA S2 S1 VB S2 S1 VC S2 Neutral 1 2 3 4 5 6 7 8 9 10 11 A C B A B C N

Feeder 1 TO LOAD Feeder 2 TO LOAD Connections Summation Meter A B C N S1 VA S2 S1 VB S2 S1 VC S2 Neutral 1 2 3 4 5 6 7 8 9 10 11 Summation CT s S1 S2 S1 S2 S1 S2 P1 P2 P1 P2 P1 P2 P1 P2 P1 P2 P1 P2 A B C N S1 S2 S1 S2 S1 S2 A B C S1 S2 S1 S2 S1 S2

Connection Current Transformer

Common Mistakes Line and load swapped on whole current meters. The voltage connections for the respective phases A, B & C (L1, L2, & L3) must match the voltage designated inputs to the meter. The current transformer connections for the respective phases A,B & C must match the associated voltage phases to the meter. The current transformers (CT s) need to be oriented properly. Each current transformer indicate the Primary (P1, P2) and Secondary (S2, S1). Incorrect CT rations.

Tools to verify the installation Meter display Display indications Instrumentation Software Instrumentation (Live Link) Verification checks Security data Load profile events and flags

Tools to verify the installation Display indicators

Tools to verify the installation Display - Instrumentation

Tools to verify the installation Display - Quadrants

Tools to verify the installation Software

Vector Diagrams 3 Phase 4 wire Unity Power Factor

Vector Diagrams 3 Phase 4 wire 30º Lag

Vector Diagrams 3 Phase 4 wire Red CT reversed

Vector Diagrams 3 Phase 4 wire All CT s reversed

Vector Diagrams 3 Phase 4 wire Red an Blue Voltages crossed

Vector Diagrams 3 Phase 4 wire Red and Blue Voltages crossed

Vector Diagrams 3 Phase 4 wire All voltages crossed

Vector Diagrams 3 Phase 4 wire All Voltages and CT s crossed

Vector Diagrams 3 Phase 3 wire Unity Power Factor

Vector Diagrams 3 Phase 3 wire 30º Lag

Vector Diagrams 3 Phase 3 wire 30º Lag, Red CT reversed

Vector Diagrams 3 Phase 3 wire Red and Blue Voltages Crossed

Vector Diagrams 3 Phase 3 wire 30º Lag, Red and Blue Voltages Crossed