Custom Contact Pins

In 1995, Tooltronics began designing and manufacturing custom test sockets for the power electronics and relay industries. A critical component of these sockets is the Kelvin contact pin. After extensive research, we found that existing suppliers could not provide a solution that met our requirements for orientation accuracy, current capacity, and reliable mechanical retention. As a result, Tooltronics developed and began manufacturing our own Kelvin contact technology.

Our Kelvin contacts were designed to solve three key challenges common in relay and power device testing:

1. Precise pin orientation for reliable contact with rotated hook pins and square or rectangular device leads
2. Higher current capability for demanding power electronics testing
3. Stable vertical retention without the need for epoxy or adhesives

To achieve this, Tooltronics uses 0.015" thick Beryllium Copper for improved current capacity and durability. Our Kelvin pins also utilize an obround-shaped injection molded insulator, which ensures precise orientation and secure positioning compared to traditional round insulator designs.

Contacts are manufactured from Beryllium Copper and finished with 30 microinches of gold over 200 microinches of boron nickel, providing superior conductivity, corrosion resistance, and long service life in demanding test applications.

LPK Kelvin Contacts

Our standard LPK Kelvin contact pins are widely used in relay and semiconductor test sockets.

• LPK-100 – Designed for 0.100" minimum spacing
• LPK-125 – Designed for 0.150" minimum spacing

These contacts are available as individual components or integrated into custom test sockets and fixtures.

High Current Kelvin Contacts

For higher power applications, Tooltronics offers High Current Kelvin Contacts rated up to 50 amps per side. Available options can accommodate device leads ranging from 0.025" to 0.080", providing reliable performance for demanding power semiconductor testing.

High Current PCB Mountable Contacts

Our High Current PCB Mountable Contacts provide a reliable electrical interface directly to a printed circuit board. These contacts allow devices to be inserted and tested without permanent soldering, making them ideal for development, qualification, and production testing environments. A wide range of sizes and configurations are available.

MPS Solid Pin (Non-Kelvin) Contacts

When space is limited and Kelvin sensing is not required, MPS Solid Pin contacts provide a compact and reliable alternative. These contacts are available with either a turned tail or solder cup termination, offering flexibility for various test socket and fixture designs.