The essential HV/EHV substation auxiliary facilities you should know about
Nowadays, HV/EHV substations have become pretty complex from the design point of view. Besides the main electrical equipment, which must be designed and selected correctly, there are several auxiliary facilities without which a substation would…...
PREMIUM Membership Required
This technical article/guide requires a Premium Membership. Get access to all premium HV/MV/LV technical articles, electrical engineering guides, and papers. Check out each plan's benefits and choose the membership plan that works best for you or your organization.You can choose an annually based Plus, Pro, or Enterprise membership plan.Log InSign Up
Apr 27, 2020 | Edvard

The art of determining the right cross-section of low voltage conductors
To be clear at the beginning of this article, determining the cross-section of conductors and cables is, for sure, not the most exciting part of electrical design. There are much more challenging and more exciting… Read more
Mar 16, 2020 | Edvard

The problem of induced voltages in control cables in high voltage substations
Cabling in power substation is very important due to the fact that they are the longest parts of a system and therefore act as efficient antennas that pickup and or radiate noise. In HV substations, there… Read more
Jan 13, 2020 | Edvard

How optical communication cables work and how they differ from other cables
In several previous articles I mentioned optical fibre in the context of substation automation, protection signaling, communication between electrical devices, LAN communications, etc. Now I will get into details of fibre optic basics, design, jointing/termination… Read more
May 23, 2018 | Edvard

High Voltage Cables In a Nutshell (Technology, Bonding, Installation and Service)
Differences between the electrical characteristics of overhead transmission lines and high voltage AC cables are fundamental and must be considered. This article gives a brief introduction to cable technology, with focus on the topics which…...
PREMIUM Membership Required
This technical article/guide requires a Premium Membership. Get access to all premium HV/MV/LV technical articles, electrical engineering guides, and papers. Check out each plan's benefits and choose the membership plan that works best for you or your organization.You can choose an annually based Plus, Pro, or Enterprise membership plan.Log InSign Up
May 04, 2018 | Edvard

Overhead vs. Underground Residential Distribution Circuits. Which One Is ‘Better’?
This debate continues. Both designs have advantages (see Table 1). The major advantage of overhead circuits is cost. An underground circuit typically costs anywhere from 1 to 2.5 times the equivalent overhead circuit (see Table… Read more
Nov 13, 2017 | Edvard

Sizing calculations for 20/3.3 kV, 12.5 MVA transformer feeder cable
Typical calculations for a 20kV transformer feeder cable are presented below. After correct cable voltage classification the following considerations apply: Current carrying capacity Short circuit rating Voltage drop Earth loop impedance Consider a 20/3.3 kV,… Read more
May 08, 2017 | 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 in accordance with the applicable… Read more
Feb 20, 2017 | Edvard

Specifying energy efficient motor, cabling and local power transformer
Many energy saving actions can encourage specifiers and engineers to look closely at the savings which can be made by specifying an energy efficient version of a particular component. This technical article presents the case… Read more
Jan 09, 2017 | Edvard

Five key factors to the correct cable selection and application
It is essential to know cable construction, characteristics, and ratings to understand problems related to cable systems. However, to correctly select a cable system and assure its satisfactory operation, additional knowledge is required. This knowledge… Read more
Oct 31, 2016 | Edvard

Shielding and Grounding Practices for Control Cables in EHV Substations
For several years, the increased application of solid-state devices for protective relaying and control and for electronic equipment, such as audio tones, carrier and microwave equipment, event recorders, and supervisory control equipment, in EHV substations… Read more
May 20, 2016 | Edvard

Recommended Practice For Cableways Selection and Installation
The term cableways refers to conductors and/or cables together with the means of support and protection, etc. for example: cable trays, ladders, ducts, trenches, and so on… are all cableways. This technical article covers the… Read more
Mar 14, 2016 | Edvard

Underground residential distribution – More hidden and more reliable
A classic underground residential distribution circuit is an underground circuit in a loop arrangement fed at each end from an overhead circuit (see Figure 1). The loop arrangement allows utilities to restore customers more quickly…. Read more
Mar 11, 2016 | Edvard

8 tips to avoid ground loops when dealing with signal level circuits
General recommendation is to properly design and implement the facility’s grounding system to avoid unwanted involvement of ground loops with the operation of the equipment. This kind of approach can also eliminate the need to… Read more
Jan 06, 2016 | Edvard

Electrical Design Project Of a Small Bakery
A small bakery with just a counter and storage areas is simple to design. The electrical design follows the layout for a house, but care must be taken on loading factors if direct-acting electric heaters are switched… Read more
Aug 26, 2015 | Edvard
