Testing Challenges in Large Ground Systems

Large ground systems, such as those found in substations and power stations, are an important part of the protection of the electricity supply network. They ensure that fault current will… Read more

Oct 12, 2015 | Edvard

8 Recommended Periodic Inspections of a Substation Transformer

The following periodic tests and inspections are recommended for routine maintenance of the medium power substation transformer. Gauge readings Cooling fans Control wiring Paint finish Fluid dielectric test Bushing and… Read more

Sep 02, 2015 | Edvard

4 Steps To Follow During Commissioning of a PLC System

Yes, PLC programs are never final, it is always possible to make corrections and subsequent adaptations to new system according the customer requirements. Even during commissioning, program changes are often… Read more

Aug 15, 2015 | Edvard

Resistance measurement of non-conductive walls and floors

There are certain situations where it is desirable for a room to be totally isolated from the Protective Earth conductor (e.g. for conducting special tests in a laboratory etc.). These rooms… Read more

Aug 05, 2015 | Edvard

13 Basic expressions often used in electrical testing

This is the simple list of basic terms you can often hear when testing and measurements of electrical installation (in general) is being performed. While experienced electrical engineers will find… Read more

Jul 27, 2015 | Edvard

12 Transformer Factory Tests Briefly Explained

The remainder of the twelve factory tests are briefly summarized below. The details of the test set connections and formulas of some of the listed tests are already described in… Read more

Jun 29, 2015 | Edvard

5 components of current drawn by the DC voltage testing of insulation

When DC voltage is applied to an insulation, the electric field stress gives rise to current conduction and electrical polarization. Consider an elementary circuit as shown in Figure 1 below,… Read more

Jun 19, 2015 | Edvard

Procedure for transformer lightning impulse test

The purpose of the impulse voltage test is to secure that the transformer insultations withstand the lightning overvoltages which may occur in service. Where: C1 – Impulse capacitor Rc – Charging… Read more

Jun 12, 2015 | Edvard

Maintenance and testing of overcurrent protective devices

When designing electrical distribution systems, required maintenance and testing of the overcurrent protective devices is a very important consideration. The electrical system reliability, component and circuit protection, and overall safety… Read more

May 04, 2015 | Edvard

What to check when commissioning variable speed drives

The main purpose of commissioning VSDs is to ensure that: The AC converter and motor have been correctly installed and meet the wiring and safety standards such as IEC 60364… Read more

Apr 22, 2015 | Edvard

General guidelines for online partial discharge testing of power cables

Online PD testing is becoming the topic of interest for power cable owners to ensure the safe and continuous operation of power cables. Partial discharge is a localised discharge in… Read more

Mar 30, 2015 | Ammar Anwar KHAN

Impulse withstand voltage test performed on assemblies

Only optional in the past, the impulse test which allow defining the rated impulse withstand voltage Uimp, is now a necessity thus demonstrating the strategy of the Standards directed to… Read more

Mar 02, 2015 | Edvard

Do Not Energize Oil-Filled Transformer Without Performing These 15 Tests and Checks!

The following tests and checks should be performed at a minimum to ensure that the transformer is ready to be energized. Do not energize the transformer without performing these tests… Read more

Feb 23, 2015 | Edvard

Basic Transformer Routine Test – Measurement of Winding Resistances

The resistance between all pairs of phase terminals of each transformer winding are measured using direct current. Furthermore the corresponding winding temperature is measured. The measured resistances are needed in… Read more

Feb 20, 2015 | Edvard

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

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… Read more

Jan 16, 2015 | Edvard