SERVICES

INESIGN offers a full range of services, including on-site testing of transformers, switchboards and complete substations (GIS/AIS). We also provide professional testing in our state-of-the-art test room. Rely on us for reliable, accurate and efficient testing solutions.

With the wide range of ''OMICRON'' instruments and our specialized technicians, INESING also offers testing, pre-commissioning, commissioning and on-site training services for our projects and for third parties.

Testing, commissioning and training

The testing, essential to confirm the quality of the work, verifies correct installation, functionality, safety and compliance with current technical and regulatory standards.

The main testing activities include:

Verification of Conformity: Check that the systems are installed according to the project and comply with current regulations.
Functionality and Safety: Operational tests to ensure that systems operate safely and efficiently.
Documentation: detailed reports on tests performed and any necessary corrective actions

Commissioning is highly integrated, but subsequent to testing activities and has the aim of verifying that the systems built and tested work correctly with the performance and efficiency envisaged in the project and desired by the client.

The main commissioning activities include:

Project Verification: Ensure that the building/system is designed in a coordinated manner and that all the necessary solutions are provided for correct commissioning, calibration and performance monitoring
Verification of the installation: Ensure that the plant building system is created respecting the design solutions envisaged for correct commissioning, calibration and performance monitoring
Performance Verification: Ensure that the systems achieve the performance specified in the project.
Energy Efficiency: Control of the operational efficiency of the systems to optimize energy consumption.

Training, an activity strongly required to provide operating personnel with the necessary instructions for the management and maintenance of the systems, together with complete project documentation.

Measurement of voltage ratio and check of phase displacement

The transformation ratio measurement verifies the turns ratio (N1/N2) of a transformer. This measurement detects any short circuits between turns and in context detects the magnetizing current. With our equipment we perform a three-phase measurement, this allows us to verify the phase shift of any configuration of transformers, extended delta, PST, rectifier transformers and unconventional vector groups.

Measurement of winding resistance

The measurement of the ohmic resistance of the windings is used to verify that there are no loose connections, possible non-compliant crimping or resistance variations due to possible hot spots.

Using our instrumentation, we carry out the test with the THREE-PHASE method with currents up to 33 A DC and 100 A DC in single phase.

Determination of capacitances windings-to-earth, and between windings, Measurement of dissipation factor (tan δ) of the insulation system capacitances

Determining the capacity and Tan δ (dissipation factor) of the windings and bushing of a transformer is a diagnostic test to verify the state of the insulation.

The test provides information on the integrity of the insulation of the windings and bushing, helping to prevent failures due to degradation of the insulation or presence of humidity

Measurement of Short-Circuit Impedance

The measurement of the short circuit impedance is a measurement to determine possible deformations or axial or radial displacements of the windings.

With our instrumentation we can carry out three-phase or single-phase measurements.

Measurement of d.c. insulation resistance

The measurement of insulation resistance of a transformer is defined as resistance to current loss when a direct current (DC) passes through the surface of the insulating material. The measurement of the insulation resistance of a transformer is used to evaluate the integrity of the insulation between the windings and between the windings and the ground (the core and the transformer case). This measure checks the degradation of the insulating material.

Frequency response analysis (FRA)

The frequency response measurement is performed to detect possible deformations of the windings (possible axial or radial deviations), or possible short turns, or anomalies in the core. The possible electrodynamic stresses caused by a short or electrical stresses can cause deformation and therefore possible damage which can deteriorate over time.

Each transformer has a unique frequency response, its so-called "fingerprint"

Some examples of conditions that FRA can be used to evaluate are:

- damage following a through fault or other short circuit event

- damage following a failure of the switch,

- damage during transport

Measurement of current transformers CT

Check the characteristics and correct assembly of the CTs using the following tests:

• Transformation ratio and polarity

• Ohmic resistance

• Excitation characteristics (knee point)

• Load impedance Transient CT classes and parameters

• Power factor

• Rated load, operating load

Each transformer is subjected to all quality controls and routine, type and special tests in accordance with the applied standards ((EN - IEC - ANSI - IEEE), Upon completion of the tests, an acceptance test report is issued stating the results of the tests performed.

Test performed:

Measurement of voltage ratio and check of phase displacement
Measurement of winding resistance
Measurement of short-circuit impedance and load loss
Measurement of no-load loss and current
Applied voltage test (AV)
Induced voltage test with partial discharge measurement (IVPD)
Lightning impulse test (LI,LIC,LIN,LIMT)
Switching impulse test (SI)
Measurement of Zero sequence impedance
Temperature rise test
Determination of sound level
Determination of capacitances windings-to-earth, and between windings.
Measurement of dissipation factor (tan d) of the insulation system capacitances.
Measurement of frequency response (FRA)
Measurement of d.c. insulation resistance
Leak testing with pressure for liquid-immersed transformers
Vacuum tightness test on site on liquid immersed transformers
Check of external coating