1.

1 SEQUENCE
Sequences of work proposed are as under:

Startup checks & Precommissioning Check for

Equiipments related Testing Equipment commissioning
Euipments

2.1 PRE COMMISSIONING AND TESTING PROCEDURE

2.2 PRE COMMISSIONING CHECKS
 The installation completeness of the test equipment shall be ensured from the
status of approved / commented IR.
 Visual Inspection Checks (Overall installation of system)
 Check all equipment’s for cleanliness & dust free (All insulator undamaged and clean).
 Visual Inspection Checks (Overall installation of system)
 Check all equipment’s for cleanliness & dust free.
 Check all Labeling are Correct.
 Check Danger Sign as per MEDC in Arabic and English.
 Check physical damage, gaskets, paints etc.
 Check the Tightness of the all the control and power BUSBAR / Cables.

2.3 SAFETY PRECAUTIONS

 Safety will be followed during execution of Testing & Commissioning works.
Safety procedures and precautions shall be adopted:
 Use of proper tools, instruments to be handled by authorized persons only. Use
of proper safety shoes, safety belts, safety helmets, gloves, goggles, mask,
earplugs & any other safety accessories as required during commissioning works.
 Persons engaged with this commissioning are experienced and have received
proper and adequate training related to procedures and test equipment utilized
for the particular testing activity.
 SPCCC JV Project Safety Plan & Procedures shall be followed during execution of
commissioning works.
 Make sure only the authorized persons are near the testing equipment’s / room /
building.

2.4 INSULATION RESISTANCE AND POLARIZATION INDEX

 Check the insulation resistance of the windings as per the below table and record
the values for a period of 1 min and 10 min
 Reference Applied 60 Sec 600 Sec
Voltage
HV – Earth 5kV
LV – Earth 500V
HV – LV 5kV
 Discharge test terminal after each insulation resistance measurement

2.5 VOLTAGE RATIO TEST:

 Ensure that both the primary and secondary windings are disconnected.
 Ensure the tap changer in lowest tap position.
 Apply 3 phase 415 VAC Supply across the primary terminal of the transformer.
 Measure the secondary voltage at the LV terminals.
 Observe the reading and record in the enclosed test format.
 Ensure the supply is disconnected and change the taping to the next level.
 Apply 3 Phase 415 VAC Supply across the primary Terminal of the Transformer
 Measure the secondary voltage at the LV terminals.
 Observe the reading and record in the enclosed test format.
 Repeat the above step until the highest tap.

2.6 MAGNETIC BALANCE TEST

 First Keep the Tap changer of transformer in normal position.
 Disconnect the transformer Neutral from ground
 Apply 3 Phase voltage to HV winding switch of any one individual phase voltage.
 Measure the phase to phase voltage in both HV & LV Side
 Repeat the test for by switching off the other individual phases.
 Tabulate the readings and check the supply is equally balanced.

2.7 MAGNETIZING CURRENT TEST

 Keep the Transformer tap in the Normal Position.
 Disconnect all the 4 Secondary Terminals
 Apply 415V 3 Phase supply to the primary Terminals
 Measure the Applied voltage and Current in each phase.
 Compare the values with FAT report.

2.8 WINDING RESISTANCE TEST

 Keep the Transformer tap in the Normal Position.
 Ensure the contacts at bushings are cleans.
 Using a winding resistance meter, the HV and LV winding resistance are
measured and recorded
2.9 VECTOR GROUP TEST
 For Dyn11 vector group, Keep the terminals 1U (HV R phase) & 2U (LV R phase)
shorted, a 3 phase, 415V, supply is applied on the HV side of the transformer, the
tap position is kept at service tap.
 The voltages on HV & LV are measured in all combinations as tabulated in the
test format and it is verified that the voltage 1V-2V is equal to 1V-2W and 1W-2V
is greater than 1W-2W. This could be seen in the vector diagram shown.

2.10 FUNCTIONAL TEST OF THERMO CONTROLLER AND BMS INTERFACE

 Check the connections of the sensors & probes
 Connect a temporary supply for the thermo controller.
 Set the threshold limit of the relay lesser than the ambient temperature and
check the functions of the relay accordingly.
 Activation and check the Function of BMS interface output contact of the thermo
controller for TX winding overheating by multimeter.

2.11 TORQUE TEST

Check the tightness of the following with appropriate torque wrench
 Bus Bar Joints (If Any).
 Earth cable connection.
 TAP Links.
2.12 PROCEDURE FORCOMMISSIONING OF DRY TYPE OF TRANSFORMER
 Verify that the position of the links of tap- changer is equal on all the three
phases.
 Check the correct functioning of the switches located as protection of the
transformer on HV & LV side.
 Check the settings of the RMU OC & EF protection relay.
 Check the setting the Thermal protection relay of the transformer
  Switch ON the Transformer feeder of the RMU.
 Check for any abnormal noise in the transformer
 Check the indication in the MDB
 Check the secondary output voltage of the transformer in the respective MDB
incomer.

3.1 HSE REQUIREMENTS

 Appropriate PPE (Safety Shoes & Goggles, Hi-Vi Jackets, Hard hats, Masks, Gloves
etc.) shall be worn at all times.
 Hand tools shall be of suitable capacity and in good working condition.
 Hand tools shall not be left unattended at site.
 Good housekeeping shall be observed in work areas at all times.
 Safety tool box talks shall be organized.
 Appropriate safety Warning signboards shall be placed near the work area.
 Dedicated access/egress routes will be established.
 All applicable Testing & Commissioning activities shall be carried out based on
the approved LOTO Procedure

4.1 ANNEXURE
 Inspection & Test Plan
 TEST REPORT FORMAT
 HIRA