Life Cycle Testing
Holland Nameplate performs life cycle testing to insure that our customers have a realistic expectation as to the typical number of cycles a particular design can endure. Any specific life requirements should be communicated to Holland Nameplate’s engineering department before the design begins.
Windows
The overlay materials used in membrane switches begin the process clear. Colors are screen printed on the back of the overlay material. Areas that do not have color printed on them become windows.
As mentioned in the section on hardcoats, window areas can have a variety of hardcoats or textures added to them. It is recommended that small discrete LED annunciator windows have the same texture as the background. Larger windows for LEDs, LCDs, or VFDs may need a window with less light diffusing characteristics. Window coatings in general are a
If LED displays are within .062" of the overlay, a velvet texture will usually yield acceptable readability. For distances greater than .062", we recommend a matte finish for the window coating.
If LCD displays are within .125" of the overlay, an
Insertable Legends
In some applications it is desirable to have the ability to customize some of the legends, either when the switch is assembled to the end product or in the field. This allows a customer to use one standard membrane switch for many different models of similar instruments. It also allows customizing a membrane switch for specific applications.
Switches can also be designed with legend cards that can be changed by the end user. One very successful application is a scoreboard with an insertable legend card for each sport. This allows the user to
To design a switch with insertable legends, a clear window is put into the area
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