Medium Voltage
Field Inspection and Testing of Medium-Voltage Motor Control Centres (MCCs)
Check MCC equipment for: alignment, levelness, and tightness of all bolting. Check all equipment for: removal of blocking, supports, temporary ties, and temporary wire jumpers. Check that all protective barriers are properly installed. Check door alignment of individual starter units… Read more
Oct 28, 2013 | By Edvard Csanyi
Testing and Commissioning
Eight important checks to do before powering up the dry-type transformer
The transformer should be powered up only after checking the following items: name plate ratings, parallel operation, connections: cables, busbars, tap change connections, grounding connection, thermal protective device, impurities removal and insulation resistance test. Make sure the name plate ratings… Read more
Oct 23, 2013 | By Edvard Csanyi
Electric Motor
Testing and commissioning procedure for electric motors
It should be noted that the scope of motor testing depends upon the motor type and size, this being indicated on the inspection forms. Motor vibration shall be measured in a tri-axial direction, i.e.: Point x axis – side of… Read more
Sep 20, 2013 | By Edvard Csanyi
Testing and Commissioning
Identifying The Primary And Secondary Phasor Polarities Of Transformer – Polarity Test
This is needed for identifying the primary and secondary phasor polarities. It is a must for poly phase connections. Both a.c. and d.c methods can be used for detecting the polarities of the induced emfs. The transformer is connected to… Read more
Aug 26, 2013 | By Edvard Csanyi
High Voltage
Commissioning of HV Panel – Operational and Functional Checkup
The main objective of the test is to check the proper operation function of the circuit breaker; in this test we do the following: This test is conducted by manual, Local and Remote. For the manual Operation test, we will… Read more
Jul 17, 2013 | By Edvard Csanyi
High Voltage
High voltage testing – Direct current (DC)
DC tests are used mainly to do “pressure tests” on high voltage cables. Although the cables operate with AC, AC testing is not practical. The high capacitance of the cables necessitates AC test sets with a high kVA rating to… Read more
Jun 01, 2013 | By Edvard Csanyi
Testing and Commissioning
Condition Monitoring of Transformers
It is possible to provide transformers with measuring devices to detect early signs of degradation in various components and provide warning to the operator in order to avoid a lengthy and expensive outage due to failure. The technique, which can… Read more
May 24, 2013 | By Edvard Csanyi
Testing and Commissioning
Transformer Routine Dielectric (Insulation) Test
The following insulation tests are performed in order to meet the transformer insulation strength expectations. Unless otherwise requested by the customer, the following test are performed in the following order (IEC 60076-3) : To confirm the insulation of the transformer terminals… Read more
May 23, 2013 | By Edvard Csanyi
Testing and Commissioning
Erection Procedure for Power Transformer
This technical article deals with transformers and their installation so we restrict ourselves here to the procedures associated with their commissioning. Transformers should be inspected for internal or external damage, particularly if they have been dropped or tipped over. This should include such… Read more
May 20, 2013 | By Edvard Csanyi
Testing and Commissioning
When a transformer has stomach pain and wants to…
During normal operation, transformer internal structures and windings are subjected to mechanical forces due to the magnetic forces. These forces are illustrated in Figure 1. By designing the internal structure very strong to withstand these forces over a long period of… Read more
May 08, 2013 | By Edvard Csanyi
High Voltage
Erection procedure for HV switchgear (Part 2)
Continued from first part: Erection procedure for HV switchgear (Part 1) Positioning of the cubicles should start near to the centre of the switchboard, installing as early as possible the enclosures associated with any special chambers or trunking. The first… Read more
May 01, 2013 | By Edvard Csanyi
High Voltage
Erection procedure for HV switchgear (Part 1)
Before commencing erection of HV switchgear check that all connections are tight on busbars and on main circuits as well as auxiliary circuits. Examine the insulation very carefully, because there have been reported cases of burned out connections due to… Read more
Apr 29, 2013 | By Edvard Csanyi
Testing and Commissioning
Transformer Routine Test – Measurement of Voltage Ratio and Check of Phase Displacement
The no-load voltage ratio between two windings of a transformer is called turn ratio. The aim of measurement is: Confirming the no-load voltage ratio given in the customer order specifications, determining the conditions of both the windings and the connections… Read more
Mar 02, 2013 | By Edvard Csanyi
Testing and Commissioning
Transformer Routine Test – Measurement Of No-Load Loss And Current
The no-load losses are very much related to the operational performance of a transformer. As long as the transformer is operated, these losses occur. For this reason, no load losses are very important for operational economy. No-load losses are also… Read more
Feb 18, 2013 | By Edvard Csanyi
Cables
Testing and Commissioning of MV/HV Cables
Compare cable data with drawings and specifications. Inspect exposed sections of cables for physical damage. Inspect bolted electrical connections for high resistance using one or more of the following methods: Use of a low-resistance ohmmeter in accordance with Section 1.2 above…. Read more
Jan 12, 2013 | By Edvard Csanyi
