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AmpSize

Cable screen earthing selector

Hanapin kung saan i-earth ang screen, drain wire o armour.

AS/NZS 3000Data na nire-review pa

Reads AS/NZS 3000:2018 and HELUKABEL and LAPP catalogues 2024. Tables checked 27 Sept 2026.

Subukan ang isang job 5

Nilalagyan ng halimbawang value ang bawat job. Palitan ang mga ito ng sarili mong value.

Mga input

Worked example gamit ang mga default na input.

Ang ginagawa ng screen
Screen laban sa interference
Screen construction
Foil at braid
Kailangang i-earth ang cable na ito ayon sa Cl 5.4.1
Oo
May double insulation ang screen sa pagitan nito at ng live conductor, at may kabuuang covering
Hindi
Ano ang sinusuri ninyo
Hum loop o circulating current
Dumidikit ang sheath sa pipe na may dalang nasusunog na ahente
Hindi

Earthing arrangement

Isang dulo, sa origin

Clause
AS/NZS 3000:2018 Cl 5.5.3.2(b)
Dahilan
Earth the screen at the end where the cable leaves its switchboard or accessory. One earthing point leaves no closed path through the screen. No current then circulates in it, and no hum loop forms.
Kinakailangang continuity
Oo
Screen construction
Foil at braid
Tala sa construction
Overall foil with a tinned copper braid over it. The catalogue puts this construction against both low-frequency and high-frequency interference. Manufacturer data, not a standard. Source: HELUKABEL Industrial Ethernet Cables, SF/UTP ranges.
Pinagmulan ng construction
manufacturer-data

Design aid lang ang resultang ito. I-verify ito laban sa kasalukuyang standard.

Mga hakbang ng kalkulasyon

  1. Screen roleemc-screen

    AS/NZS 3000:2018 Cl 5.5.3.2(b)

  2. Tugmang case ng clausea screen, armour or sheath on a cable or cord that needs earthing

    AS/NZS 3000:2018 Cl 5.5.3.2(b)

  3. Earthing arrangementResultaIsang dulo, sa origin

    AS/NZS 3000:2018 Cl 5.5.3.2(b)

  4. Kailangan ang continuityOo

    AS/NZS 3000:2018 Cl 5.5.4.3

  5. Ang sinusuri mohum-loop
  6. Konstruksyon ng screenFoil at braid

    HELUKABEL and LAPP catalogues 2024

  7. Kumikilos laban, ayon sa catalogueboth

    HELUKABEL and LAPP catalogues 2024

Tungkol sa calculator na ito

How this is calculated

The tool reads AS/NZS 3000:2018 Clause 5.5.3.2 for where a cable screen, drain wire or armour is earthed. It then states what that choice does to hum loops and touch voltage.

  1. Role. You pick what the metal does, such as an EMC screen.
  2. Clause case. The tool matches your role, your earthing need and your double-insulation answer to a case in Cl 5.5.3.2.
  3. Arrangement. It gives the earthing arrangement for that case. For an EMC screen against hum, this is one end, at the origin.
  4. Continuity. It reads Cl 5.5.4.3 for the continuity the screen needs. The screen and its fittings stay continuous.
  5. Concern. It states the effect on your concern. One earthing point leaves no closed path through the screen, so no hum loop forms.
  6. Construction. It adds the catalogue note for the screen type. This is maker data, not a Standard.
StepTable or clauseWhat it decides
ArrangementAS/NZS 3000 Cl 5.5.3.2Where the screen is earthed
ContinuityCl 5.5.4.3The screen and fittings stay continuous
Construction noteHELUKABEL and LAPP catalogues 2024What the screen type acts against

Worked example

A foil and braid EMC screen with a hum loop concern. The tool gives one end, at the origin, from Cl 5.5.3.2(b). Continuity is required.

Limits

  • The tool gives the safety arrangement of AS/NZS 3000. It does not give an EMC design.
  • No document the tool holds backs earthing both ends for EMC. Check the device maker guide or IEC 61918.
  • The gland advice is an AmpSize recommendation, not a requirement.
  • The tool does not check the current rating of the screen.

See also: Segregation checker, Control panels and PLC wiring and The MEN system.

Mga tanong

Design aid ang resulta. I-verify ito laban sa kasalukuyang standard.

Saan naka-earth ang cable screen?

Binabanggit ng AS/NZS 3000:2018 Clause 5.5.3.2(b) ang originating end at hindi nagtatakda ng bilang ng earthing points. I-earth ang screen, armour o sheath na kailangang i-earth kung saan lumalabas ang cable sa switchboard o accessory nito. Walang binabanggit na both-ends arrangement ang standard, kaya walang ibinibigay ang tool.

Pinipigilan ba ng earthing sa isang dulo ang hum loop?

Oo. Kapag isang earthing point lang, walang saradong daan sa screen, kaya walang current na dumadaloy dito at walang nabubuong hum loop. Ang pag-earth sa screen sa dalawang punto ang lumilikha ng daang iyon.

Kailan hindi kailangang i-earth ang screen?

Ang Clause 5.5.3.2(b) ay may dalawang exception. Ang una ay nangangailangan ng double insulation sa pagitan ng screen o braid at ng live conductors. Kailangan din nito ng non‑conductive covering sa ibabaw ng cable. Dapat malayo sa live at exposed na conductive parts ang bawat joint at termination. Ang ikalawa ay sumasaklaw sa anumang kasong hindi saklaw ng Clause 5.4.1.

Puwede bang maging earthing conductor ang screen?

Oo, sa ilalim ng Clause 5.3.2.2(ii), na may isang kondisyon mula sa Clause 5.3.2.3(b). Bawat live conductor na nagpapakain sa equipment ay dapat tumakbo sa parehong cable na iyon. Hinihingi rin ng Clause 5.5.4.3 ang continuity, at impedance na tumutugma sa copper earthing conductor.

Saan galing ang payo sa screen construction?

Mula sa HELUKABEL at LAPP catalogues. Manufacturer data iyon, hindi standard, at ganito ang label ng tool dito. Ang braid ay pangunahing laban sa low-frequency interference at ang foil ay laban sa high-frequency interference. Termination hardware ang sakop ng mga catalogue. Wala sa kanila, at wala rin sa AS/NZS 3000, ang sumusuporta sa both-ends arrangement.

Background

Mga clause at table na binabasa ng tool na ito

Bawat clause at table, kasama kung paano ito na-verify

Huling na-check ang mga table noong 27 Sept 2026.

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