Overview
IEC 60738-1-3:2008 is an IEC blank detail specification for directly heated positive step‑function PTC thermistors intended for inrush current applications (Assessment level EZ). It is a supplementary document to the generic specification and defines the required style, layout and minimum content for any detail specification addressing PTC inrush-current devices. Detail specifications that do not follow this blank are not considered compliant with IEC requirements. This edition (2.0, 2008) is to be read together with the generic IEC 60738‑1 document.
Key topics and requirements
- Scope and identification
- Identification elements to be inserted in a detail specification (organization, reference numbers, device description, outline drawing, assessment level EZ).
- Mechanical and material data
- Method(s) of mounting, dimensions (gauging), coating, termination types and suitability for soldering, and flammability/solvent resistance statements.
- Electrical ratings & characteristics
- Mandatory parameters and units to be specified: operating temperatures, maximum voltage, zero‑power resistance (series/parallel), isolation/insulation values (if insulated), minimum/maximum peak‑to‑peak inrush current, and residual current.
- Marking, packaging and ordering
- Marking requirements per IEC 60738‑1, packaging details (bulk/tape), and minimum ordering information.
- Inspection & test schedules
- Defined lot‑by‑lot (Group A/B) and periodic (Group C) inspection tables with sampling, severities and acceptance criteria; requirements for qualification approval and quality conformance.
- Referenced test methods
Applications and who uses this standard
- Manufacturers of PTC inrush current limiters: to prepare compliant detail specifications and define product datasheets.
- Design and application engineers: to ensure component selection meets required inrush limiting performance and environmental/assembly constraints.
- Quality, test and compliance teams: to implement lot inspection, qualification testing and supplier approval in accordance with IEC procedures.
- Procurement and standards officers: to reference unambiguous procurement requirements and ensure IEC conformity claims are valid.
Related standards
- IEC 60738‑1 (Generic specification - read in conjunction)
- IEC 60068‑2‑58 (Environmental testing - solderability / soldering heat)
- IEC 60410 (Sampling plans and inspection by attributes)
Keywords: IEC 60738-1-3:2008, thermistors, PTC thermistors, inrush current, blank detail specification, assessment level EZ, quality conformance, test schedule, IEC 60738-1.