Version: 3.0
Date: 23/05/2016
Lucy HV Air Metering Unit 5 Limb Test Form
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Substation Name
Substation Number
Metering Unit Serial No
Metering Unit Make/Type / Lucy Sabre AMU
System Configuration / 3-PHASE 3-WIRE
Current Transformer / L1 / L2 / L3
Location / METERING UNIT / METERING UNIT / METERING UNIT
Serial Number **
Burden (output VA) *** / VA / VA / VA
Accuracy Class / 0.5 / 0.5 / 0.5
Make ***
Type / WOUND / WOUND / WOUND
Available Ratios / 400/200/100/5A / 400/200/100/5A / 400/200/100/5A
Ratio Selected / A / A / A
Pole P1 Facing Distribution System? / YES / NO * / YES / NO * / YES / NO *
Voltage Transformer / L1 / L2 / L3
Location / METERING UNIT / METERING UNIT / METERING UNIT
Serial Number **
Burden (output VA) *** / VA / VA / VA
Accuracy Class / 0.5 / 0.5 / 0.5
Make**
Type / 3P / 3P / 3P
Available Ratios / 11000/6600/110V / 11000/6600/110V / 11000/6600/110V
Ratio Selected / V / V / V
* Delete as applicable. ** Available from manufacturers test certificates. *** Available from nameplate.
Voltage Transformer Tests
VT Configuration ChecksCheck metering multi-core cable disconnected / (ü)
Check correct metering VT ratio selected (terminals 31 to 39) see TABLE 1 below / (ü)
Ensure label on lid of terminal box matches VT voltage ratio selected / (ü)
Check correct NPD VT Ratio selected (terminals 47 to 55) see TABLE 2 below / (ü)
Check LV VT fuse ratings are correct (6A) and continuity (L1, L3 & N) / (ü)
Check NPD fuse ratings are correct (2A) and continuity (da ) / (ü)
Check 110V auxiliary fuse ratings are correct (2A) and continuity / (ü)
Check LV fuses and links are installed / (ü)
Check HV links are closed in tank / (ü)
TABLE 1 Metering VT Voltage Range Selection
Phase / Metering VT 11000/110V / Common Terminal / Metering VT 6600/110V
L1 / E210 (33) / E11 (32) / E110 (31)
L2 / E230 (36) / E31 (35) / E130 (34)
L3 / E250 (39) / E51 (38) / E150 (37)
TABLE 2 NPD VT Voltage Range Selection
Phase / NPD VT 11000/110V / Common Terminal / NPD VT 6600/110V
L1 / E510 (49) / E185 (48) / E410 (47)
L2 / E530 (52) / E171 (51) / E430 (50)
L3 / E550 (55) / E173 (54 / E450 (53)
VT Resistance Tests
Check secondary earth links in place (terminal 46 and 58) / (ü)
Measure the resistance of the VT L1 primary winding (L1 to Earth) * / kW
Measure the resistance of the VT L2 primary winding (L2 to Earth) * / kW
Measure the resistance of the VT L3 primary winding (L3 to Earth) * / kW
Measure the resistance of the VT L1 to L2 primary winding * / kW
Measure the resistance of the VT L2 to L3 primary winding * / kW
Measure the resistance of the VT L3 to L1 primary winding * / kW
* Measure from the HV bushing or busbar in HV metering unit to earth, the resistance of the star connected VT to earth is 1 to 2 kΩ and 2 to 4 kΩ between phases using a multi-meter
VT Insulation Resistance – 1kV Insulation Resistance Tester
Disconnect the secondary earth links (terminal 46 and 58) / (ü)
Measure insulation resistance of metering VT secondary (across terminal 46) / MW
Measure insulation resistance of NPD VT secondary (across terminal 58) / MW
Reconnect the secondary earth links (terminal 46 and 58) / (ü)
VT Phasing Check – Primary Injection
Remove fuses and links L1, L2, L3 and N also fuses da and cn / (ü)
Check the metering circuit breaker is open / (ü)
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 Voltage / HV / Secondary (LV) Winding Voltage (measured at fuse)
NPD
da–cn** / L1 – L2 / L2 – L3 / L3 – L1
L1 L2 / V / V (nominal) / V (< nominal) / V (< nominal)
L2 L3 / V / V (< nominal) / V (nominal) / V (< nominal)
L3 L1 / V / V (< nominal) / V (< nominal) / V (nominal)
Replace fuses L1, L2 and L3 (6A) / (ü)
Replace fuses da and cn (2A) / (ü)
* These voltages are for an injection test set and if a mains supply is used the results may differ.
** The NPD voltage measured should be in the order of 0.5 to 2V.
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 TesterCTs isolated or HV dead / (ü)
Disconnect CT star point earth (terminal 20) / (ü)
Measure the insulation resistance (D70 – D90 at terminal 20) / MW
Reconnect CT star point earth (terminal 20) / (ü)
CT Ratio Check – Primary Injection or Prevailing Load*
Phase / CT Ratio
Primary Current / CT Ratio Secondary Current / Injected Primary Current* / Calculated Secondary Current / Measured Secondary Current / Ratio Correct
[A] / [B] / [C] / [D = B / A * C] / [E] / [E = D]
L1 / 100A / 5A / 50 / 100A / A / A / A / (ü)
L2 / 100A / 5A / 50 / 100A / A / A / A / (ü)
L3 / 100A / 5A / 50 / 100A / A / A / A / (ü)
L1 / 200A / 5A / 50 / 100A / A / A / A / (ü)
L2 / 200A / 5A / 50 / 100A / A / A / A / (ü)
L3 / 200A / 5A / 50 / 100A / A / A / A / (ü)
L1 / 400A / 5A / 50 / 100A / A / A / A / (ü)
L2 / 400A / 5A / 50 / 100A / A / A / A / (ü)
L3 / 400A / 5A / 50 / 100A / A / A / A / (ü)
On completion of test ensure correct CT ratio 3 (100A), ratio 2 (200A) or ratio 1 (400A) as specified by designer is selected / (ü)
* Delete as applicable.
CT Polarity – Flick Test
Check L1 phase CT polarity – secondary CT connection D11 (+ve) to D70 (-ve) / (ü)
Check L2 phase CT polarity – secondary CT connection D31 (+ve) to D70 (-ve) / (ü)
Check L3 phase CT polarity – secondary CT connection D51 (+ve) to D70 (-ve) / (ü)
CT Relationship to VT Output
L1 CT associated with L1 voltage ** / (ü)
L2 CT associated with L2 voltage ** / (ü)
L3 CT associated with L3 voltage ** / (ü)
** 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 [1] / 7.5 / VA
Final Checks /
Reconnect metering multi-core cable (if disconnected) / (ü)
If metering multi-core cable is not connected leave CTs shorted (D11, D31,D51, D70) / (ü)
Check all covers are secured and appropriate lock fitted to lid / (ü)
Complete asset data form and submit to ART / (ü)
Test Equipment
Purpose/Make/Type / Serial Number / Calibration Expiry Date
Certification
All tests have been 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 together with the CT/VT calibration certificates shall be placed in a plastic wallet in the meter terminal box (for the meter operator).
A copy of the completed test forms and the CT/VT calibration certificates shall be sent to the ART mailbox (, , ).
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Lucy HV Air Metering Unit 5 Limb Test Form / Document Number: ECP 11-0515bVersion: 3.0
Date: 23/05/2016
Figure 1 – Lucy Air Metering Unit / Figure 2 – Lucy AMU Legend and Wiring Diagram on Rear of Terminal Box Cover
Figure 3 – Lucy AMU Terminal Box Cover with Selected VT and CT Ratios (example only) / Figure 4 – Lucy AMU Terminal Box with Cover Removed
[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.