helena snyman - technical manager and sydney bhengu ... · helena snyman - technical manager and...

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


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


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.


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.



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.



Calibration of metering installation

components (SANAS)

Instrument transformers

Test certificates

Current transformers

Voltage transformers

Voltage transformer burdening



Meter panel ancillary equipment

Test blocks

Meters

General requirements

Meter type testing

Meter calibration

Meter numbering


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.


4.6 Metering equipment installation

General (Training)

Meter panel (enclosure)

Instrument transformer earths

Wiring loom

Measurement of current

Measurement of voltage


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

Connections Single Phase, Two Wire, Whole Current

A

N

1 2 3 4

LOA

D

LIN

E

Connections Three Phase, Four Wire, Whole Current

A

B

C

N

A B C N

1 2 3 4 5 6 7 8 9 10 11

S1 VA S2 S1 VB S2 S1 VC S2 Neutral

A

B C

LOA

D

LIN

E

Connections Three Phase, Four Wire, CT Connected

A

B

C

N

A B C N

1 2 3 4 5 6 7 8 9 10 11


A

B C

TO L

OA

D

P1 P2

S1 S2

P1 P2

S1 S2

P1 P2

S1 S2

Connections Three Phase, Three Wire, CT Connect

A

B

C

N

A B C N

1 2 3 4 5 6 7 8 9 10 11


TO L

OA

D

A

B

C

Connections Summation

A

B

C

N

TO L

OA

D

Fee

de

r 1

A

B

C

TO L

OA

D

Fee

de

r 2

A B C N

1 2 3 4 5 6 7 8 9 10 11


S1 S2

S1 S2

S1 S2

S1 S2

S1 S2

S1 S2

S1 S2

P1 P2 P1 P2 P1 P2 P1 P2 P1 P2 P1 P2

S1 S2 S1 S2

Meter

Summation CT’s

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

helena snyman - technical manager and sydney bhengu ... · helena snyman - technical manager and...

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