oSIST prEN 2591-217:2026

• Abstract:

  This document specifies a method for measuring the voltage drop under specified current in terminal lugs and in-line splices.; It is used together with EN 2591-100.

• Status: Not Published
• Public Enquiry End Date: 04-Mar-2026
• ICS: 49.060 - Aerospace electric equipment and systems
• ICS: 49.090 - On-board equipment and instruments
• Technical Committee: I13 - Imaginarni 13
• Current Stage: 4020 - Public enquire (PE) (Adopted Project)
• Start Date: 16-Jan-2026
• Due Date: 05-Jun-2026
• Completion Date: 05-Mar-2026
• Ref Project: FprEN 2591-217 - Aerospace series - Elements of electrical and optical connection - Test methods - Part 217: Voltage drop under specified current for terminal lugs and in-line splices

• Revises: SIST EN 2591-217:2004 - Aerospace series - Elements of electrical and optical connection - Test methods - Part 217: Voltage drop under specified current for terminal lugs and in-line splices
• Effective Date: 19-Jan-2023

oSIST prEN 2591-217:2026 is a draft European standard in the aerospace series, published through CEN and distributed by SIST. It specifies a method for measuring voltage drop under specified current in terminal lugs and in-line splices. The document is used together with EN 2591-100, so it is meant for test and qualification work under the wider aerospace electrical and optical connection test framework.

What does oSIST prEN 2591-217:2026 specify?

oSIST prEN 2591-217:2026 specifies how to measure voltage drop in terminal lugs and in-line splices when a specified current is applied. In practice, it tells a test laboratory or supplier how to prepare the specimen, how to set up the measurement, and how to calculate the result.

The document is organized into five clauses and a bibliography:

• Clause 1 - Scope
• Clause 2 - Normative references
• Clause 3 - Terms and definitions
• Clause 4 - Preparation of specimens
• Clause 5 - Method
• Bibliography - EN 2591-100

Clause 1 also states that the document is used together with EN 2591-100, so the general test-method rules come from the companion part while this part covers the voltage-drop test itself.

What are the key requirements of oSIST prEN 2591-217:2026?

The main practical requirements are in Clause 4 and Clause 5. They define how to prepare the test pieces, what to measure, and how to judge the result.

• Specimen preparation - Clause 4 requires specimens to be fitted with their normal accessories and wired according to the technical specification. This matters because the test should reflect the intended build condition, not a special laboratory setup.
• Technical specification data - Clause 4 requires the technical specification to state the number of specimens, cable type, installation and wiring, the length L between the measurement points, the test current, fitted accessories, and whether initial and final measurements are required. This means the acceptance test must be defined before testing starts.
• Measurement set-up - Clause 5 measures the voltage drop of the specimen and the reference cable between the measuring points shown in Figures 1 and 2. This gives a controlled comparison between the connection and the reference conductor.
• Calculation method - Clause 5 calculates the voltage drop of the connection by subtracting the voltage drop of the reference cable from the measured drop of the specimen. Separate formulas are given for terminal lugs and for in-line splices, so the result is handled according to connection type.
• Acceptance criterion - Clause 5 states that the calculated voltage drop shall not exceed the value specified in the technical specification. In practice, the standard gives the method, while the product requirement comes from the project or procurement document.
• Temperature correction - Clause 5 includes an optional normalization of voltage-drop values to 20 °C when the technical specification calls for it. This is important when test temperatures vary and results need to be compared on the same basis.
• Distance correction - Clause 5 says that if the distance between the measurement points is different from L, the measured values are adjusted to that distance by calculation. That keeps results comparable even if the test arrangement is not exactly the nominal one.

What terms does oSIST prEN 2591-217:2026 use?

The document uses a small set of core terms in the method.

• Terminal lugs - Connection elements at the end of a conductor, tested here for voltage drop under current.
• In-line splices - Connection elements joining conductors in line, tested with their own calculation formula.
• Specimen - The test item under evaluation, prepared and wired as described in the technical specification.
• Reference cable - The comparison conductor used to remove the voltage drop of the cable run from the measured result.
• Measurement points - The points between which voltage drop is measured, as shown in the figures.
• Test current - The current level specified for the measurement and used for both the specimen and the reference cable.
• Crimp - The connection whose voltage drop is calculated by comparison with the reference cable.

Who uses oSIST prEN 2591-217:2026?

This standard is used by aerospace manufacturers, connector suppliers, test laboratories, and quality teams working on electrical connection elements. It is relevant when a company needs to verify the electrical performance of terminal lugs or in-line splices under a defined current.

Buyers and engineers use it to set a clear test requirement in a technical specification. Quality managers use it to check that a supplier’s test method and acceptance result match the agreed aerospace test practice.

What changed in oSIST prEN 2591-217:2026 from the previous edition?

oSIST prEN 2591-217:2026 supersedes EN 2591-217:2002. The foreword states two technical changes:

• a formula was added to normalize measurements at 20 °C for power terminal lugs and splices
• the measurement points in Figure 1 and Figure 2 were corrected

Which standards are used with oSIST prEN 2591-217:2026?

EN 2591-100 is the companion part named with this document. It provides the general test-method framework used together with this voltage-drop method.

What does the oSIST prEN 2591-217:2026 document contain?

The document contains the test method, the specimen preparation rules, the calculation approach, and the measurement layouts for terminal lugs and in-line splices. It also includes two figures showing the measurement assemblies and formulas for connection voltage drop, reference-cable subtraction, and optional normalization to 20 °C.

For a reader preparing a test plan, the most useful parts are Clause 4 for defining the specimen and Clause 5 for defining how the measurement is made and how the result is adjusted before comparison with the specified limit.

SLOVENSKI STANDARD
01-marec-2026
Aeronavtika - Električni in optični spojni elementi - Preskusne metode - 217. del:
Padec napetosti pri določenem toku za kabelske čevlje in vrstne spojke
Aerospace series - Elements of electrical and optical connection - Test methods - Part
217: Voltage drop under specified current for terminal lugs and in-line splices
Luft- und Raumfahrt - Elektrische und optische Verbindungselemente; Prüfverfahren -
Teil 217: Spannungsabfall bei festgelegtem Strom für Kabelschuhe und Stoßverbinder
Ta slovenski standard je istoveten z: prEN 2591-217
ICS:
49.060 Letalska in vesoljska Aerospace electric
električna oprema in sistemi equipment and systems
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
EUROPEAN STANDARD
prEN 2591-217
NORME EUROPÉENNE
EUROPÄISCHE NORM
December 2025
ICS 49.060 Will supersede EN 2591-217:2002
English Version
Aerospace series - Elements of electrical and optical
connection - Test methods - Part 217: Voltage drop under
specified current for terminal lugs and in-line splices
Luft- und Raumfahrt - Elektrische und optische
Verbindungselemente; Prüfverfahren - Teil 217:
Spannungsabfall bei festgelegtem Strom für
Kabelschuhe und Stoßverbinder
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee ASD-
STAN.
If this draft becomes a European Standard, CEN 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.

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Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.

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COMITÉ EUROPÉEN DE NORMALISATION

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© 2025 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 2591-217:2025 E
worldwide for CEN national Members.

prEN 2591-217:2025 (E)
Contents Page
European foreword . 3
1 Scope . 4
2 Normative references . 4
3 Terms and definitions . 4
4 Preparation of specimens . 4
5 Method .
...