Category Archive for: «Testing and Commissioning»

Page 1 of 41234»

Inspection, Test and Measurement Procedures for LV and MV (up to 36kV) Switchgears

Importance of checks and maintenance Installed in clean, well ventilated or air-conditioned locations, switchgear will require little routine maintenance. Major inspection should be scheduled for power plant shutdowns and concentrate for low voltage switchboards on identifying contact wear, correct operation of interlocks, correct overload settings and fuse sizes, signs of overheating, and undue dirt or corrosion. For MV […]

Read More

Test On 110kV Power Cable After Installation (3)

General description of site test procedure In previous two parts of this technical article first six procedures were explained. Now the last three (7, 8 and 9) will be explained in details: Phase indication test (part 1) DC conductor resistance measurement (part 1) Capacitance test (par 1) DC Sheath test on outher sheath (part 2) Insulation resistance […]

Read More

Test On 110kV Power Cable After Installation (2)

General description of site test procedure In previous part of this technical article first three procedures were explained. Now the rest will be explained in details: Phase indication test (previous part) DC conductor resistance measurement (previous part) Capacitance test (previous part) DC Sheath test on outher sheath Insulation resistance measurement Cross bonding check Zero sequence and […]

Read More

Test On 110kV Power Cable After Installation (1)

General description of site test procedure Site test procedure covers all necessary electrical testing for the 110 kV cable and accessories to be carried out during and after installation of the cable system. 110 kV, 115 kV and 132 kV XLPE Cables (Standard Reference is IEC 60840 and relevant SEC Transmission Specifications 11-TMSS-02, Rev. 0 […]

Read More

Transformer Routine Test – Partial Discharge Measurement

Transformer insulation structure This routine test aims to measure the partial discharges which may occur in the transformer insulation structure during test. Partial-discharges are electrical arks which form the surges between electrodes of any area of the insulating media of a transformer between the conductors. These discharges may occur in air bubbles left in the […]

Read More

Testing of Power Transformer – Measurement of Zero-Sequence Impedance

Earth-fault protection Purpose of the measurement The zero-sequence impedance is usually measured for all star-connected windings of the transformer. The measurement is carried out by supplying a current of rated frequency between the parallell connected phase terminals and the neutral terminal. The zero-sequence impedance per phase is three times the impedance measured in this way. […]

Read More

Why is Continuous On-line Monitoring of Partial Discharge in the Switchgear Necessary?

What’s the condition of your switchgear? Not sure? You know that periodical maintenance test like partial discharge test can still leave switchgear in virtually unknown condition. Insulation defects and deterioration may very well develop in service within maintenance cycle. These defects are often not detectable with traditional off-line tests and yet, traditionally, on-line or off-line […]

Read More

How to measure insulation resistance of a motor

Winding insulation resistance If the motor is not put into operation immediately upon arrival, it is important to protect it against external factors like moisture, high temperature and impurities in order to avoid damage to the insulation. Before the motor is put into operation after a long period of storage, you have to measure the […]

Read More

Erection Procedures of Earthing Arrangements (TNC, TN-S, TNC-S and TT)

Earthing of low voltage networks The earthing of low voltage networks in the UK is largely determined by the Low Voltage Supplies. However, if the incoming supplies are at 11kV and the transformers are in the ownership of the user, the LV supplies may be earthed in a less conventional way using a high impedance. […]

Read More

Inspection and Test procedures for Instrument Transformers

Procedures to follow: Visual and Mechanical Inspection Electrical Tests: Electrical Tests – Current Transformers Electrical Tests – Voltage Transformers Electrical Tests – Coupling-Capacitor Voltage Transformers Electrical Tests – High-Accuracy Instrument Transformers (Reserved) Test Values: Test Values: Visual and Mechanical Test Values: Current Transformers – Electrical Test Values:Voltage Transformers – Electrical Test Values: Coupling Capacitor Voltage […]

Read More
Page 1 of 41234»


Subscribe to Weekly Download Updates //
(free electrical software, spreadsheets and EE guides)

EEP's Android Application
Electrical Engineering Daily Dose
Daily dose of knowledge and news from
Electrical Engineering World