Pre-commissioning tests and in-service checks of protection system
The pre-commissioning tests need to be carefully programmed so that they take place in a logical and efficient order, in order that no equipment is disturbed again during subsequent tests…. Read more
Jun 14, 2017 | By Edvard

Commissioning substation busbars in an efficient and modern way
The commissioning procedure of substation busbars for differential protection and other busbar protection schemes involves a large number of input and output circuits that require a verification check in both… Read more
Jun 13, 2017 | By Edvard

Generation of high voltages in the lab (AC/DC, switching and lightning impulse)
Benjamin Franklin – The man who dared to fly his kite in a thunder storm! In this technical article laboratory tests and test equipment needed to assess the performance of… Read more
May 29, 2017 | By Edvard

PLC power supply and safety (emergency) circuits requirements
The source for a PLC power supply is generally single-phase and 120 or 240 VAC. If the controller is installed in an enclosure, the two power leads (L1 hot and… Read more
Mar 15, 2017 | By Edvard

Performing power factor test on dry-type transformer during commissioning
The power factor test is a maintenance test used to determine the insulation system dielectric power loss by measuring the power angle between an applied AC voltage and the resultant… Read more
Mar 01, 2017 | By Edvard

Measurement of N–PE loop resistance in TN, TT and IT systems
Up-to-date test instruments, with built in modern electronics, can measure loop resistance even between the neutral N and protection PE conductors in spite of possible high currents in the neutral… Read more
Feb 24, 2017 | By Edvard

Guidelines for high potential (Hi-Pot) DC testing of medium voltage cables
This technical article provides general guidelines for high potential “Hi-Pot” DC testing of MV power cables. All tests made following cable installation and during the warranty period must be performed… Read more
Feb 20, 2017 | By Edvard

The easiest way to measure ground resistance using clamp meter, but be carefull!
The ground clamp meter / tester is an effective and time-saving tool when used correctly because the user does not have to disconnect the ground system to make a measurement… Read more
Feb 06, 2017 | By Edvard

Transformer exterior inspection and tests you MUST perform periodically
Periodic transformer exterior inspection (visual) reveals important condition information. For example, valves positioned incorrectly, plugged radiators, stuck temperature indicator and level gauges, and noisy oil pumps or fans. Oil leaks… Read more
Jan 25, 2017 | By Edvard

Commissioning of protection relays using test equipment and software
Commissioning and maintenance With numerical protection relays commissioning and maintenance has become far less complicated as a result of the information provided by the devices as well as the integrated… Read more
Jan 16, 2017 | By Edvard

Troubleshooting dead circuit by testing continuity with disconnected supply
Dead circuit testing is testing performed with the power disconnected from the circuit. The main benefit of disconnecting power supply while tests with an external energy source are performed is… Read more
Nov 28, 2016 | By Edvard

3 good ways to improve earth electrode resistance
When you find that your earth electrode resistance is not low enough, there are several ways you can improve it: Lengthen the earth electrode in the earth Use multiple rods… Read more
Nov 25, 2016 | By Edvard

High voltage station – Design, construction and commissioning process
Having selected the right site location for high voltage station, the design construction and commissioning process would broadly follow the steps shown in Figure 1. Recent trends in utilities have… Read more
Nov 11, 2016 | By Edvard

Using Megger tester for these 3 types of insulation resistance tests
You know that good insulation has high resistance and poor insulation relatively low resistance. The actual resistance values can be higher or lower, depending upon such factors as the temperature… Read more
Nov 04, 2016 | By Edvard

3 easy measures for a good PLC system maintenance
Why need for PLC system maintenance when they are designed to be easy to maintain and to ensure trouble-free operation? Well, several maintenance aspects should be considered once the system… Read more
Nov 02, 2016 | By Edvard
