Cable lines - screen bonding / 22.09.2025

Earth continuity conductor

Today we will not talk about alcohol (“bar”), but about a conductive element called:✅ equipotential bar (bar, bus);✅ earth continuity conductor (ECC). Questions arise:1️⃣ why do we need such a bar;2️⃣ how to provide equal distances from the bar to all phases A,B,C;3️⃣ how to calculate the optimal bar material and cross section (Fb). Unfortunately,

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Cable lines - screen bonding / 11.09.2025

Cost of losses in cable screens

When designing cable lines, we use software to check ampacity, taking into account the key influencing factors:✅ cross-section of cable elements;✅ the mutual arrangement of phases and circuits;✅ screens’ bonding type;✅ laying conditions;✅ environmental parameters. It turns out that almost every software known in the cable industry calculates ampacity perfectly, and also helps with calculating

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Cable lines - ampacity / 07.08.2025

Cable ampacity calculation mistake

For medium voltage (MV) line, usually, screens of single-core cables are grounded at both sides. Let us assume that we have two separate MV lines, differing in the mutual arrangement of three single-core cables:Line 1️⃣ – trefoil;Line 2️⃣ – in row. In the conditions of the example, according to the book, we get the following

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Cable lines - transients / 19.07.2025

Screen bonding cable length

We know that the screen’s cross-bonding is an effective way to deal with induced currents and losses in the screens of 6-500 kV cable lines (CL). The use of cross-bonding allows not only to save on losses (dozens of thousands of euros annually), but also to increase the permissible core current of the cable line,

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Cable lines - screen bonding / 07.07.2025

Sheath voltage limiter selection

For lines with single-core cables, there is a problem of selecting the optimal screens’ bonding type. It is especially relevant for 110-500 kV lines, where grounding of screens on both sides is almost prohibited, and 99% of lines have either grounding of screens on one side or cross-bonding of screens. In both cases, it is

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Cable lines - various topics / 29.05.2025

Cable outer sheath strength

To design the cable line, we need to pass the following stages:✅ Evaluate the electrical strength of the cable outer sheath (jacket) and agree on what is the permissible voltage on the screen.✅ Select the grounding/bonding scheme of the screens (number of sections, cycles, etc.)✅ Perform the thermal calculation of the cable line and select

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Cable lines - screen bonding / 19.05.2025

Bad cable line length

We have to design the cable length that the customer wants. However, let’s discuss which line length would be particularly inconvenient for us and why. The answer to this question depends on the voltage class and the method of neutral grounding. Today, let’s only discuss 110-500 kV networks with a grounded neutral. For such networks,

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Cable lines - screen bonding / 17.03.2025

Cable screen currents

If I hadn’t paid only 100 euros in taxes, I would be a criminal. If AC 6-35 kV networks are being massively built all over the world (for example, to connect windfarms to the grid), where each cable line has tens and thousands of euros of useless power losses in screens, then this is called

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