ecp 11-0515c schneider hv metering unit 3 limb test...

ECP 11-0515c Schneider HV Metering Unit 3 Limb Test Form

Schneider HV Metering Unit 3 Limb Test Form

Document Number: ECP 11-0515c

Version: 3.0

Date: 27/06/2018


Note: This form is based on drawing RMSCH-MU6-N36 Rev F and G; the terminal, fuse and link designations on units built to earlier revisions may differ.

Full Postal Address

Import MPAN

Export MPAN

Substation Name

Substation Number

Metering Unit Serial No

Metering Unit Make Type

Schneider MU6-N36

System Configuration

3-PHASE 3-WIRE

Current Transformer

L1

L3

Location

METERING UNIT

METERING UNIT

Serial Number **

Burden (output VA) **

VA

VA

Accuracy Class

0.5

0.5

Make **

Type

WOUND

WOUND

Available Ratios

400/200/5A

400/200/5A

Ratio Selected

A

A

Pole P1 Facing Distribution System?

YES / NO *

YES / NO *

Voltage Transformer

L1

L3

Location

METERING UNIT

METERING UNIT

Serial Number ***

Burden (output VA) ***

VA

VA

Accuracy Class

0.5

0.5

Make***

Type

3P

3P

Available Ratios

11000/6600/110V

11000/6600/110V

Ratio Selected

V

V

* Delete as applicable. ** Available from CT label. *** Available from VT label.

Voltage Transformer Tests

VT Configuration Checks

Check metering multi-core cable disconnected

()

Check correct metering VT ratio selected (terminals 15 to 20) see TABLE 1 below

()

Ensure label on lid of terminal box matches VT voltage ratio selected

()

Check 110V auxiliary fuse F1 rating is 2A and continuity

()

Check VT fuse F2 and F3 ratings are 6A and continuity

()

Check white LV links LK4, LK5, LK6 are installed

()

TABLE 1 Metering VT Voltage Range Selection

Phase

Metering VT 6600/110V

Common

Metering VT 11000/110V

L1

E110 (terminal 15)

E30 (terminal 16)

E210 (terminal 17)

L3

E150 (terminal 18)

E50 (terminal 19)

E250 (terminal 20)

VT Insulation Resistance – 1kV Insulation Resistance Tester

Check secondary earth link LK6 in place

()

Measure the insulation resistance of VT primary (HV) winding (L1 to Earth)

M

Remove secondary earth white link LK6

()

Measure insulation resistance of VT secondary winding (across white link LK6)

M

Replace secondary earth white link LK6

()

VT Phasing Check – Primary Injection

Remove fuses F2 and F3

()

Remove white link LK5

()

Check the metering circuit breaker is open

()

Apply 240/110V ac from an injection test set to the primary (HV) winding, measure each of the secondary (LV) winding voltages and compare to the values in the table below*

Primary (HV) Winding

Secondary (LV) Winding Voltage (measured at fuse/link)

Voltage

Bushing

L1 – L2(F2 – LK5)

L2 – L3(LK5 – F3)

L1 – L3(F2 – F3)

L1 – L2

V (nominal)

V

V

L2 – L3

V

V (nominal)

V

L3 – L1

V

V

V (nominal)

Replace link LK5

()

Replace 6A fuses F2 and F3

()

* These voltages are for an injection test set and if a mains supply is used the results may differ.

VT Primary (HV) Rated Voltage

VT Nominal Secondary (LV) Winding Voltage with 240/110V applied to the Primary (HV) Winding

240V

110V

11kV

2.4V

1.1V

6.6kV

4.0V

1.8V

Current Transformer Tests

CT Insulation Resistance – 1kV Insulation Resistance Tester

Check CTs isolated or HV dead

()

Measure the insulation resistance (D70 – D90 at terminal 10)

M

Disconnect CT star point earth (terminal 10)

()

Measure the insulation resistance (D70 – D90 at terminal 10)

M

Reconnect CT star point earth (terminal 10)

()

CT Polarity – Flick Test

Open CT shorting-links (terminals 1 and 2)

()

Check L1 phase CT polarity – D11 at terminal 1 (+ve) to D70 at terminal 10 (-ve)

()

Check L3 phase CT polarity – D51 at terminal 2 (+ve) to D70 at terminal 10 (-ve)

()

CT Ratio Check – Primary Injection or Prevailing Load*

Phase

CT RatioPrimary Current

CT Ratio Secondary Current

Injected Primary Current*

Calculated Secondary Current

Term

Measured Secondary Current

Ratio Correct

[A]

[B]

[C]

[D = B / A * C]

[E]

[E = D]

L1

200A

5A

50 / 100A

A

A

1-10

A

()

L3

200A

5A

50 / 100A

A

A

2-10

A

()

L1

400A

5A

50 / 100A

A

A

1-10

A

()

L3

400A

5A

50 / 100A

A

A

2-10

A

()

On completion of test ensure correct CT ratio low (200A) or high (400A) as specified by designer is selected

()

* Delete as applicable.

CT Relationship to VT Output at Terminal Box

L1 CT associated with L1 voltage **

()

L3 CT associated with L3 voltage **

()

** If all CT and VT tests are correct the CT relationship to the VT is proven and the above can be ticked

CT Burden

Maximum CT burden per phase at metering unit terminal box

0.5

VA

Maximum CT burden per phase at meter terminal box [footnoteRef:1] [1: The maximum CT burden is based on 20 metres of 12-core 2.5mm2 or 40 metres of 19-core 2.5mm2 copper cable with a resistance of 0.0068 Ω/m at 20oC and a CT rated secondary current of 5A.]

7.5

VA

Final Checks

Reconnect metering multi-core cable (if disconnected)

()

If metering multi-core cable is not connected leave CTs shorted – close shorting links (terminals 1 and 2)

()

Check all covers are secured and appropriate lock fitted to lid

()

Complete asset data form and submit to ART

()

Test Equipment

Purpose/Make/Type

Serial Number

Calibration Expiry Date

Certification

CT and VT calibration certificates attached

()

All tests completed satisfactorily

()

Comments

Organisation

Test Operative Name

Date of Tests

Test Operative Signature

A copy of the completed test form together with the CT/VT calibration certificates shall be placed in a plastic wallet in the metering unit terminal box.

A copy of the completed test form and the CT/VT calibration certificates shall be sent to the relevant ART mailbox ([email protected], [email protected], [email protected]).

A copy of the completed test form and the CT/VT calibration certificates shall also be attached to the relevant operation on the work order or the relevant PO in the contractor portal.

This page is left intentionally blank.

THIS IS AN UNCONTROLLED DOCUMENT, THE READER MUST CONFIRM ITS VALIDITY BEFORE USE


Version: 3.0

Date: 27/06/2018



Version: 3.0

Date: 27/06/2018

© UK Power Networks 2018 All rights reserved 6 of 6

Figure 1 – Schneider MU6 Metering Unit

Figure 2 – Terminal Box with Cover Removed

F1 LK4 F2 LK5 LK6 F3

1 2 10

Figure 3 – Fuses and Links

Figure 4 – Terminal Block

Figure 5 – CT Labels

Figure 6 – VT Labels

This page is left intentionally blank.



Version: 3.0

Date: 27/06/2018

ecp 11-0515c schneider hv metering unit 3 limb test...

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