SIST EN 3373-011:2009

SIST EN 3373-011:2009 is the Slovenian adoption of EN 3373-011:2009 from CEN for aerospace terminal lugs. It specifies nickel plated, ring-shaped terminals for crimping on copper conductors, for metric and inch stud series, and for use up to 260 °C. The standard is intended to be used together with EN 3373-001.

What does SIST EN 3373-011:2009 specify?

SIST EN 3373-011:2009 sets the product requirements for a specific family of crimpable terminal lugs used in aerospace electrical connections. It covers the lug type, the stud series it fits, the temperature range, the dimensional envelope, and the identification and packaging information needed for supply and control.

The document is organized into 10 clauses:

• Scope
• Normative references
• Terms and definitions
• Characteristics
• Dimensions and mass
• Designation
• Quality assurance
• Details of assembly tooling
• Marking
• Packaging

It also relies on Table 1 for dimensions, Table 2 for test applicability, and Figure 1 for the marking area.

What are the key requirements of SIST EN 3373-011:2009?

SIST EN 3373-011:2009 requires the lug design to suit aerospace use on metric and inch stud series, with service at temperatures up to 260 °C. In practice, this means the part must match the stud system and the environmental duty expected in high-temperature aircraft installations.

Product characteristics and construction

Clause 4 sets the operational range and gives basic workmanship requirements. The lugs must have smooth surfaces without burrs or sharp edges, and if a split barrel construction is used, the split must remain permanently sealed after crimping. This matters because sharp edges and an opening split can weaken the connection or damage adjacent wiring.

Dimensions, mass and identification

Clause 5 points to Table 1 and Figure 1 for the required dimensions and mass. The table covers multiple conductor sizes and stud sizes, and the document states that these dimensions are based on metric conversions of SAE-AS 20659. Clause 6 defines the designation format, which uses the standard reference, an item code and the product description block. That gives manufacturers, buyers and inspectors a common ordering and traceability language.

Quality assurance, testing and tooling

Clause 7 requires quality assurance in accordance with EN 3373-001. Table 2 then identifies the test methods that apply to this product, including visual examination, dimensions and mass, voltage drop, ageing, salt mist, vibration, tensile strength and low-temperature crimping. For users, that means acceptance is tied to a defined test regime rather than a simple visual check.

Clause 8 controls assembly tooling. Crimping tools must conform to MIL-DTL-22520, and the clause also identifies tool families and die requirements for larger conductor sizes. In practice, this helps keep the crimp process consistent and prevents using unsupported tooling.

Marking and packaging

Clause 9 requires the item code and the manufacturer's monogram to be embossed in the marking area, using EN 2424 Style F. Clause 10 requires the package marking to show the EN designation, the manufacturer's name, part number, quantity, date of manufacture and batch number. This supports traceability in receiving inspection, stock control and maintenance release.

What terms does SIST EN 3373-011:2009 define?

For this document, the terms and definitions from EN 3373-001 apply. The main terms used here are:

• Terminal lug - a crimpable connector terminal used to join a conductor to a stud.
• Crimping - the mechanical compression process used to attach the lug to the conductor.
• Stud series - the metric or inch stud sizes for which the lug is designed.
• Item code - the code from Table 1 used in the designation and marking.
• Manufacturer's monogram - the maker's identifying mark embossed on the lug.
• Quality assurance - the control framework used to verify conformity with EN 3373-001.

Who uses SIST EN 3373-011:2009?

SIST EN 3373-011:2009 is used by aerospace electrical equipment makers, wire harness assemblers, test laboratories, quality managers and buyers of electrical connection hardware. It is relevant when selecting terminal lugs for crimped copper connections in high-temperature aerospace installations and when specifying tooling, inspection and marking requirements.

Which standards are used with SIST EN 3373-011:2009?

• EN 3373-001 - provides the technical specification framework, shared terms and the quality assurance basis.
• EN 2424 - gives the marking style used for embossing the lug.
• *EN 2591- ** - supplies the test methods used in Table 2 for visual, electrical, mechanical and environmental verification.
• SAE-AS 20659 - is the dimensional basis from which the lug dimensions are derived.
• MIL-DTL-22520 - sets the general requirements for the crimping tools.
• MS25441 - identifies a crimping tool used for higher conductor sizes.
• MS90485 - identifies the die dimensions for larger conductor sizes.

What does the SIST EN 3373-011:2009 document contain?

The document contains a product standard, not a general tutorial. Its main technical content is the scope, the shared references, the application of EN 3373-001 terms, and the product characteristics for ring-shaped nickel plated terminal lugs.

It also includes a detailed dimension table for wire size and stud size combinations, a designation system, a table showing which EN 2591 test methods apply, and assembly-tooling guidance. Figure 1 shows the marking area, which supports correct identification and traceability during manufacture and inspection.