EN 50181:2010

Plug-in type bushings above 1 kV up to 52 kV and from 250 A to 2,50 kA for equipment other than liquid filled transformers

This European Standard is applicable to insulated bushings for maximum voltages above 1 kV up to 52 kV, rated currents from 250 A up to 2 500 A and frequencies from 15 Hz up to 60 Hz for equipment other than liquid filled transformers. This European Standard establishes essential dimensions, to ensure adequate mounting and interchangeability of mating plug-in separable connectors of equivalent ratings.

Steckbare Durchführungen über 1 kV bis 52 kV und von 250 A bis 2,50 kA für Anlagen anders als flüssigkeitsgefüllte Transformatoren

Traversées embrochables de tensions supérieures à 1 kV jusqu'à 52 kV et de 250 A à 2,50 kA pour équipements autres que transformateurs immergés dans un liquide

La présente Norme Européenne s'applique aux traversées isolées pour des tensions maximales supérieures à 1 kV jusqu’à 52 kV, des courants assignés de 250 A à 2 500 A et des fréquences allant de 15 Hz à 60 Hz, pour les équipements autres que les transformateurs immergés dans un liquide. La présente Norme Européenne fixe les dimensions essentielles, afin d’assurer le montage correct et l’interchangeabilité des connecteurs séparables embrochables correspondants, de caractéristiques assignées équivalentes.

Vtični skoznjiki za napetosti nad 1 kV do 52 kV in tokove od 250 A do 2,50 kA za opremo, razen za transformatorje, polnjene s tekočinami

Ta evropski standard velja za izolirane skoznjike za maksimalno napetost od 1 kV do 52 kV, ocenjene tokove od 250 A do 2 500 A in na frekvencah od 15 Hz do 60 Hz za opremo, razen za transformatorje, polnjene s tekočinami. Ta evropski standard vzpostavlja potrebni obseg za zagotavljanje primernega nameščanje in medsebojne zamenljivosti za paritev priključnih konektorjev enakovrednih ocen.

General Information

• Status: Published
• Publication Date: 08-Jul-2010
• ICS: 29.080.20 - Bushings
• Technical Committee: CLC/TC 36A - Insulated bushings
• Drafting Committee: CLC/TC 36A - Insulated bushings
• Parallel Committee: IEC/SC 36A - IEC_SC_36A
• Current Stage: 9093 - Decision to confirm - Review Enquiry
• Start Date: 16-Mar-2022
• Completion Date: 23-Sep-2025
• Ref Project: SIST EN 50181:2010 - Plug-in type bushings above 1 kV up to 52 kV and from 250 A to 2,50 kA for equipment other than liquid filled transformers

Relations

• Replaces: EN 50181:1997 - Plug-in type bushings above 1 kV up to 36 kV and from 250 A to 1,25 kA for equipment other than liquid filled transformers
• Effective Date: 28-Jan-2023

Overview

EN 50181:2010 is a European Standard established by the CLC (European Committee for Electrotechnical Standardization) that governs plug-in type bushings used in electrical equipment other than liquid filled transformers. It applies to bushings designed for maximum voltages above 1 kV up to 52 kV and rated currents ranging from 250 A to 2,500 A, operating at frequencies between 15 Hz and 60 Hz. This standard specifies essential mechanical dimensions and electrical requirements to ensure interchangeability and compatibility of plug-in separable connectors with equivalent ratings.

By adhering to EN 50181:2010, manufacturers and users can guarantee that plug-in type bushings will fit properly and function reliably, facilitating safe and efficient connection, installation, and maintenance in medium-voltage electrical systems.

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Key Topics

Scope and Application

• Applies to insulated bushings with voltages from 1 kV to 52 kV.
• Rated current levels include 250 A, 400 A, 630 A, 800 A, 1,250 A, 1,600 A, 2,000 A, and 2,500 A.
• Suitable for equipment other than liquid-filled transformers, such as switchgear and other medium-voltage devices.
• Covers frequencies from 15 Hz to 60 Hz.

Standardized Dimensions

• Defines interface types (labelled A to F for outside cone and numbered 0 to 3 for inside cone bushings) to ensure mechanical and electrical interchangeability.
• Specifies detailed dimensions for outside cone and inside cone plug-in bushings including mounting distances, contact sizes, and bail holder configurations.
• Ensures standardized mating between bushings and separable connectors for easy plug-in/out operation.

Electrical and Mechanical Requirements

• Electrical rating in accordance with IEC 60038 voltage classes: 12 kV, 24 kV, 36 kV, and 52 kV.
• Compliance with EN 60137 for separately supplied bushings.
• Emphasis on proper material selection for bushing contacts and conductors to avoid corrosion, especially when mixing different metals.
• Optional features include bail holders designed to prevent accidental disconnection of separable connectors.

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Applications

EN 50181:2010 is essential for the design, manufacture, and usage of medium-voltage electrical equipment requiring plug-in type bushings, including but not limited to:

• Switchgear and controlgear assemblies: Ensuring consistent bushing connections that facilitate maintenance and reduce downtime.
• Medium-voltage equipment installations: Providing reliable electrical insulation and mechanical stability for cable connections.
• Replacement parts and upgrades: Interchangeability allows equipment owners to source bushings from different manufacturers without compatibility issues.
• Substation components: Supporting robust electrical connections above 1 kV with standardized dimensioning.

This standard supports industries such as utilities, industrial plants, railways, and renewable energy systems, where medium-voltage electrical equipment reliability and ease of service are critical.

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Related Standards

EN 50181:2010 references and complements several key standards for electrical insulation and medium-voltage equipment, including:

• EN 60137 - Insulated bushings for alternating voltages above 1,000 V, which covers general requirements and testing methods for bushings.
• IEC 60038 - Standard voltages, supplying the standard nominal voltage values referenced in EN 50181.
• IEC Guide 109 and CENELEC TC 111X documents - Provide environmental guidelines concerning the entire lifecycle of electrotechnical products, encouraging minimal environmental impact.
• Other national standards aligned under the CENELEC framework to harmonize medium-voltage bushing specifications across Europe.

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Why EN 50181:2010 Matters

Adhering to EN 50181:2010 ensures:

• Safety and reliability by standardizing insulation and electrical parameters in medium-voltage plug-in bushings.
• Interchangeability, enabling equipment compatibility and reducing custom engineering efforts.
• Ease of maintenance through separable connectors that can be safely connected or disconnected.
• Lifecycle efficiency by facilitating replacement parts sourcing and minimizing equipment downtime.
• Environmental consideration by recommending materials and designs that reduce environmental impact.

For manufacturers, designers, and operators of medium-voltage electrical installations, EN 50181:2010 offers a clear and practical framework for integrating plug-in type bushings that meet European regulatory and performance expectations.

Standards Content (Sample)

SLOVENSKI STANDARD
01-september-2010
1DGRPHãþD
SIST EN 50181:1997
9WLþQLVNR]QMLNL]DQDSHWRVWLQDGN9GRN9LQWRNRYHRG$GRN$]D
RSUHPRUD]HQ]DWUDQVIRUPDWRUMHSROQMHQHVWHNRþLQDPL
Plug-in type bushings above 1 kV up to 52 kV and from 250 A to 2,50 kA for equipment
other than liquid filled transformers
Steckbare Durchführungen über 1 kV bis 52 kV und von 250 A bis 2,50 kA für Anlagen
anders als flüssigkeitsgefüllte Transformatoren
Traversées embrochables de tensions supérieures à 1 kV jusqu'à 52 kV et de 250 A à
2,50 kA pour équipements autres que transformateurs à remplissage de liquide
Ta slovenski standard je istoveten z: EN 50181:2010
ICS:
29.080.20 Skoznjiki Bushings
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN 50181
NORME EUROPÉENNE
July 2010
EUROPÄISCHE NORM
ICS 29.080.20 Supersedes EN 50181:1997

English version
Plug-in type bushings above 1 kV up to 52 kV and from 250 A to 2,50 kA
for equipment other than liquid filled transformers

Traversées embrochables de tensions Steckbare Durchführungen über 1 kV
supérieures à 1 kV jusqu'à 52 kV bis 52 kV und von 250 A bis 2,50 kA
et de 250 A à 2,50 kA pour équipements für Anlagen anders als flüssigkeitsgefüllte
autres que transformateurs à remplissage Transformatoren
de liquide
This European Standard was approved by CENELEC on 2010-07-01. CENELEC members are bound to comply
with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard
the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on
application to the Central Secretariat or to any CENELEC member.

This European Standard exists in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CENELEC member into its own language and notified
to the Central Secretariat has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus,
the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy,
Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia,
Spain, Sweden, Switzerland and the United Kingdom.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Management Centre: Avenue Marnix 17, B - 1000 Brussels

© 2010 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 50181:2010 E
Foreword
This European Standard was prepared by the Technical Committee CENELEC TC 36A, Insulated bushings.
It was submitted to the Unique Acceptance Procedure and was approved by CENELEC as EN 50181 on
2010-07-01.
This document supersedes EN 50181:1997.
The main technical changes on the Plug-in type bushings are:
– Enlarge the scope of the voltage class from the plug-in bushings from 36 kV to 52 kV;
– Upgrading the current capacity of the existing defined bushings;
– Introduce a new bushing interface for 52 kV.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN and CENELEC shall not be held responsible for identifying any or all such patent rights.
The following dates were fixed:
– latest date by which the EN has to be implemented

at national level by publication of an identical
national standard or by endorsement (dop) 2011-07-01

– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2013-07-01
__________
– 3 – EN 50181:2010
Contents
Introduction . 4
1 Scope . 4
2 Normative references . 4
3 Definitions . 4
4 Requirements . 5
4.1 Application . 5
4.2 Standard values of maximum voltage (U ) . 5
m
4.3 Standard values of rated current (Ir ) . 5
4.4 Compliance . 5
4.5 Bushing mounting distance . 5
4.6 Detail dimensions of plug-in type bushings . 5
Figures
Figure 1 - Interface dimensions of outside cone plug-in type bushings . 6
Figure 2 - Bushing details of outside cone plug-in type bushings . 7
Figure 3 - Outer dimensions of inside cone plug-in type bushings . 9
Figure 4 - Interface details of inside cone plug-in type bushings . 10
Tables
Table 1 - Interface dimensions . 6
Table 2 - Bushing dimensions . 8
Table 3 - Bushing dimensions . 9
Table 4 - Interface dimensions . 11

Introduction
The object of this European Standard is to specify the requirements to ensure interchangeability of bushings
for maximum voltages above 1 kV up to 52 kV and rated currents from 250 A to 2 500 A for equipment other
than insulating liquid filled transformers.
1 Scope
This European Standard is applicable to insulated bushings for maximum voltages above 1 kV up to 52 kV,
rated currents from 250 A up to 2 500 A and frequencies from 15 Hz up to 60 Hz for equipment other than
liquid filled transformers.
This European Standard establishes essential dimensions, to ensure adequate mounting and
interchangeability of mating plug-in separable connectors of equivalent ratings.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.

EN 60137, Insulated bushings for alternating voltages above 1 000 V

1)
IEC Guide 109 and Cenelec TC 111X document , Environmental aspects − Inclusion in electrotechnic
...