Measuring Electrical Contact Noise in Sliding Electrical Contacts

B615: Standard Practice for Measuring Electrical Contact Noise in Sliding Electrical Contacts

In the realm of electromechanical systems, the integrity of electrical contacts is paramount. Unforeseen noise can degrade signal quality, lead to intermittent failures, and compromise the reliability of critical components. For engineers and designers working with sliding electrical contacts, understanding and controlling this noise is essential. ASTM B615 provides an authoritative framework for achieving this, offering a comprehensive standard practice for its measurement.

What is B615?

ASTM B615, "Standard Practice for Measuring Electrical Contact Noise in Sliding Electrical Contacts," is an industry-leading document developed by ASTM International. It establishes a standardized methodology for quantifying the electrical noise generated at the interfaces of sliding electrical contacts. The primary purpose of this standard is to ensure consistent, repeatable, and technically sound measurements, facilitating reliable engineering evaluations and quality control.

Scope & Purpose

This standard governs the practices and critical factors involved in measuring electrical contact noise specifically within sliding electrical contact systems. It outlines the necessary test conditions, apparatus, and reporting requirements to enable accurate noise characterization. While B615 focuses on the measurement of contact noise, it does not address the inherent safety hazards associated with the materials or equipment used, which remain the user's responsibility.

Who Must Comply?

• • Primary audience: Electrical Engineers, Materials Scientists, Test Engineers, Quality Control Technicians, and Research Scientists involved in the design, testing, or manufacturing of components with sliding electrical contacts.
• • Industries affected: Electronics Manufacturing, Aerospace, Automotive, Telecommunications, and Research Institutions.
• • Compliance nature: Voluntary, but highly recommended for ensuring product quality and comparability across different testing facilities.
• • Enforcement: Typically enforced through internal quality assurance protocols, customer specifications, and industry best practices.

Key Requirements Overview

Professionals utilizing ASTM B615 must adhere to several core requirements:

• • Comprehensive Test Condition Reporting: The standard mandates detailed reporting of all relevant electrical (e.g., current, source voltage, load impedance), mechanical (e.g., contact velocity, wipe rate), and environmental (e.g., temperature, lubrication, atmosphere) parameters during testing.
• • Appropriate Apparatus Selection: Key provisions include specifying the use of suitable measurement instruments, such as oscilloscopes or RMS voltmeters, with adequate frequency response and shielding to prevent external interference.
• • Distinction of Noise Sources: Professionals must ensure that measured noise is attributed to the contact interface itself, distinguishing it from induced voltages or acoustic noise.
• • Two Primary Test Types: The standard differentiates between Type I (qualification/acceptance testing simulating end-use) and Type II (research/tribological studies with varied parameters) testing, each with distinct objectives and parameter control.
• • Baseline Noise Measurement: It is crucial to establish and record a baseline noise level with static contacts to ensure its insignificance compared to the operational noise.

Related Standards & References

ASTM B615 often complements other ASTM standards that delve into the material properties and performance of electrical contacts. For instance, standards related to contact resistance measurements (e.g., ASTM B182 for friction and wear testing, which can influence contact noise) and material specifications for contact alloys provide foundational data that can inform B615 testing. Understanding the tribological behavior of contact surfaces