Environmental Sealing - Overview
Overview | Design Considerations
GENERAL INFORMATION: The gasket, which is placed under the graphic overlay of the membrane switch keypad, insulates the layers that constitute the membrane switch keypad circuit. Placed on the perimeter of the part, this gasket prevents the infiltration of liquids, moisture and various substances inside the membrane switch keypad. GGI International recommends the integration of a perimeter gasket in all cases where the keypad assembly may be subjected to high levels of humidity and other extreme environmental conditions.
ENVIRONMENTAL FACTORS:
GGI International's engineering staff can recommend and design a membrane switch keypad assembly that will withstand various environmental conditions. Adding a gasket to the keypad will eliminate or minimize the effect of the following factors:
- Variations in temperature
- Variations of pressure
- Liquid substances
- Moisture
- Chemicals
- Particulates of polluting agents
IP Values: Here's an efficient way for you to evaluate your needs with regards to protection against infiltration and contaminants. Simply provide GGI with the IP Value to which your product must comply. The IP Value (International Protection) is a two-digit classification standard that specifies the level of sealing of an electronic product. The first digit indicates protection from contaminating solids and the second digit refers to protection from contaminating liquids.
The values of these codes are as follows:
| 1st digit | Protection from contaminating solids | 2nd digit | Protection from moisture and contaminating liquids |
|---|---|---|---|
| 0 | No protection | 0 | No protection |
| 1 | Protection from particles bigger than 50 mm. | 1 | Protection from vertical water drops. |
| 2 | Protection from particles bigger than 12 mm. | 2 | Protection from water drops having an angle of approach of 15 degrees. |
| 3 | Protection from particles bigger than 2.5 mm. | 3 | Protection from the rain (an angle of approach of 60 degrees). |
| 4 | Protection from particles bigger than 1 mm. | 4 | Protection from projected water. |
| 5 | Protection from dust. | 5 | Protection from projected water from a hose. |
| 6 | Complete seal from dust. | 6 | Protection from projected water from a hose in a powerful and concentrated fashion. |
| 7 | Protection from a temporary immersion. | ||
| 8 | Protection from continuous immersion. | ||
For example: A membrane switch keypad requiring thorough sealing, an IP65 level may be required. This means that the membrane switch keypad assembly should be sealed against dust and resist the projection of water from a hose.