Mobile computers are quite often exposed to and operated within less than ideal conditions. They can be exposed to dust, moisture, extreme temperatures, or UV radiation outside of standard office space, which is temperature controlled, and relatively clean and dry. How the device is designed to withstand these conditions is very important to how it will perform, as well as survive in extreme conditions.
The mobile computer industry uses a standardized rating system for determining how resistant a device is to damage from “ingress” of water and dust. Understanding condensation and what drives it is key to understanding the limitations of devices to withstand condensation and perform the tasks needed in different use cases.
Extreme temperatures and, in particular, the transition between extreme temperatures can provide a different path for moisture to create potential damage without it “leaking” into the product.
Another factor concerning a mobile computer outside the office space is the effect of extremely high or low temperatures on battery performance and life.
We examine considerations that must be addressed in order for mobile computers to withstand extreme conditions. It also lists various options when choosing devices for their particular applications.
A standardized Ingress Protection (IP) rating classifies and rates the level of sealing effectiveness provided by mechanical casings and electrical enclosures for a specified application. The IP rating indicates ingress protection for a new product.
A product’s IP rating can, and often does, degrade after the product is dropped and/or exposed to environmental hazards that compromise the material strength, such as a chemical attack, extreme temperatures, impact forces, or other factors due to distortion, cracking, and structural degradation that may occur.
It should also be noted that IP sealing provides little protection against internal condensation formation as the device transitions between warm, humid areas, and refrigerated/air conditioned or freezer environments.
IP Rating System Overview
The international IP rating system, IEC 60529, utilizes the two letters “IP”, followed by two numbers, as follows:
The first number (X) represents a product's resistance to the intrusion of particles or dust.
The second number (Y) represents a product's resistance to the intrusion of liquid (standardized testing uses distilled water).
The highest rating level for dust protection is 6, and for water protection it is 8. An IP rating of “IP67” represents a level 6 for dust protection and level 7 for water protection.
The British standard for IP is EN 60529. While slightly different in the details, it is largely the same as the more universal IEC 60529.
IEC 60520 IP Ratings (Dust and Water)