Potted Electronics2016-12-12T14:15:05-05:00

Potted Electronics

by David Barnett, P.E.

Elzetta Modular Flashlights have earned the title, “The Toughest Flashlights on the Planet”.  They have been used as hammers, shot with shotguns, and dropped from helicopters.  Elzetta Modular Flashlights are not just tougher than other flashlights, they are orders of magnitude tougher than other flashlights.  The key to this extreme durability lies primarily in two factors.  First is the solid acrylic optical lenses (see blog on Beam Projection for more information).  The other key ingredient is fully-potted electronics.

To understand the importance of potted electronics, one must have a basic knowledge of circuit board construction.  In the simplest terms, a circuit board is comprised of electrical components held to a fiberglass/copper board by thin solder joints.  The solder is made of a tin alloy which, by nature, has very poor mechanical properties.  With solder joints in modern electronics commonly measuring less than 1 mm in thickness, the force required to break these spindly tin connections is pitifully small.  A short drop to the floor is often adequate to fracture a solder joint which, in most cases, will render the circuit board in operable.

Enter electrical potting.  This technology has been around for decades and is used to harden many aviation and critical military electronics.  Potting compound is a thermoset substance that is applied in liquid form and subsequently solidifies to a rigid structure with strong mechanical properties.   When dispensed into a housing that contains electronics and/or circuit boards, the liquid potting compound fills the housing and flows around every electrical component and every solder joint.  The potting compound then hardens and locks everything together into one solid structural mass.  (It’s a bit like pouring concrete on a miniature scale.  Once the concrete has cured, there is no way the rebar is going to bend or break.)  An electrical device without potting is only as strong as its weakest solder joint.  A device with electrical potting is vastly more rugged as the solder joints are completely surrounded and reinforced.   The additional strength supplied by the potting compound not only increases load bearing capabilities, but also resistance to shock, impact, and vibration.

Additionally, potting compound provides a hermetic seal for the encapsulated electronics.  This keeps all electrical components completely protected from water and other fluids that can quickly destroy unpotted devices.

It is hard to overstate the robustness that potted electronics bring to Elzetta Flashlights.  As stated before, Elzetta Modular Flashlights are not just tougher than other flashlights, they are orders of magnitude tougher than other flashlights.  Other manufacturers boast of 1.5 meter drop tests (less than 5 feet) while Elzetta Modular Flashlights have survived 300-feet drops.  Other manufacturers claim waterproofing to depths of a few meters relying on o-rings to keep water away from vulnerable circuit boards while Elzetta Modular Flashlights can be submerged to nearly any depth for any amount of time as the electronics are fully encapsulated inside the device.