Exatron 3000B
www.exatron.com 7-16 Chapter 7 Preventive Maintenance
PARTICLE INTERCONNECT CONTACT MAINTENANCEWHY CLEAN P I CONTACTS?
EXATRON'S patented Particle Interconnect ("P I") contacts can best be visualized as a microscopic bed
of nails. The nails themselves are nickel-plated diamond particles which are coated with a nickel or gold
finish. These particles are evenly distributed on a beryllium-copper or copper-clad PCB substrate,
resulting in a contact surface with a rough "nail file" appearance.
Typical PI coating on flexible BeCu Pin
One of the outstanding features of P I contacts is their ability to penetrate the build-up of oxidation on
component leads.
P I CLEANING/PREVENTIVE MAINTENANCE PROCEDUREPREPARATION - DISMANTLING THE P I CONTACT ASSEMBLY:
To clean and/or recondition your P I contacts, it is necessary to disengage the contacts from their
operating environment so that you may work with unobstructed P I surfaces. EXATRON manufactures two
types of P I contact assemblies: Handler Contactors (part #6000-242-H, compatible with Autosite
programmers,) and BP Programmer Contactors (part #6000-537-A, mounted onto a programmer
socket.)
Handler Contactor Assemblies
A. Remove the four #6-32-08 Allen bolts which hold the assembly onto the handler.
B. Place the contact assembly on a protective surface such as non-conductive i. c. packaging
foam to protect the pins on the bottom from possible damage while cleaning or re-conditioning
the contacts.
BP Programmer Contactor Assemblies
A. This contact assembly is mounted onto a programmer socket with 84 pins holding it in place.
Gently loosen each of the four sides of the contact assembly by hand and pull straight up to
remove it.