Choosing the Right Panel PC

In order to choose the right industrial panel PC for you, you will first need to determine its use and the environment it will be used in. The working environment and the intended application will determine the following elements:

• Size (starting at 3.5 inches, or about 9 cm)
• Screen format
• Screen Resolution
• Brightness and possible backlighting option
• Touchscreen option (choice between a resistive or capacitive screen)
• Rugged screen. There are generally three levels: semi-rugged, rugged and ultrarugged. The level of ruggedness is the ability to resist being dropped, vibrations, extreme temperatures, etc.
• Integration and mounting

Other characteristics should be taken into account when choosing a Panel PC, depending on your application requirements and the desired performance:

• Processor type
• Memory
• Storage
• Expansion ports (i.e. additional video outputs)

A touch screen combines display functions (screen) and pointing device functions (mouse). There are two types of touchscreen technology:

• Resistive touchscreens:

These touchscreens are made of two conductive layers separated by a layer of insulation. When the user touches a layer, the two conductive films come into contact, which causes a current to flow. The system will detect a variation in resistivity in the conductive layers and determine the coordinates of the contact point on the screen. A resistive touchscreen responds when touched by a stylus, gloved hand, bare finger, nail, etc. This type of touchscreen is also resistant to water, grease and dust.

Compared to a capacitive touchscreen, this type of touchscreen is more accurate, especially when used with a stylus. The manufacturing cost is much lower. Resistive touchscreens are more sensitive to scratches and other damage caused by sharp objects however. They are also less reactive than the capacitive touchscreens, and their reactivity decreases over time. Lastly, resistive touchscreens are less transparent, resulting in a loss of 20 to 25% of screen brightness, and the built up layers can lead to harmful reflections.

• Capacitive touchscreens:

With this technology, a layer placed on the glass face accumulates charges. When users touch the layer with their fingers, charges are transferred to them. This creates a measurable change (the electrostatic field is interrupted) on the layer, sensors then determine the coordinates of the affected area. The disadvantage of this type of technology is that it does not work when the user wears gloves.
For “multitouch” applications, it is necessary to turn to touchscreens with projected capacitive technology. This technology works with thicker screens. This means the touchscreens can be covered by a highly resistant armoured glass screen. Capacitive touchscreens are brighter, guaranteeing a transparency of over 90%.

A multi-touch screen allows the user to apply several points (several fingers) simultaneously on the screen to trigger actions. It is very intuitive to use, the most common and simple actions are zoom and rotate, but the multi-touch also allows you to change pages, for example, by swiping the screen. Another advantage of multi-touch is that actions requiring the use of two hands for critical or potentially dangerous operations can be an effective way to prevent unintentional operator errors.

Due to the interactivity of multi-touch screens, they are often recommended for educational or collaborative work purposes. However, your HMI software may not support this feature: this is something you should check before making your choice.

There are multiple mounting options that allow the panel PC to operate in various environments and applications.

It is important to think about how you want to integrate it into your work equipment (vehicles, automatons, etc.) or into your installation (technical cabinet, kiosk, etc.). You can choose between:

• A rack-mount Panel PC (with bezel for rack mounting, metal frame, server type)
• A Panel PC with a bezel frame so it can be installed from the front (panel mount)
• A Panel PC in metal casing (steel or stainless steel), a desktop or VESA version (arm, stand or base mount)

Industrial Panel PCs have many uses such as HMI in industrial PLCs, in vending and/or payment machines (i.e. interactive displays) and in all sectors requiring operator intervention.

The following standards apply depending on your use of the Panel PC:

• IP index: you should have a good understanding of the environment in order to select the necessary protection index (IP index) required. The first digit indicates protection against solids, the second digit indicates protection against water and/or liquids. Industrial Panel PCs generally have IP65 or IP67 (NEMA 4 or NEMA 6) protection.
• IK rating: the two-digit IK rating indicates the mechanical protection index protection against impact energy, given in joules. It gives the equivalent to the fall of a mass of a certain weight from a certain height. For example IK01 => material protected against an impact energy of 0.15 joules (impact equivalent to the fall of a 150 g mass from a height of 10 cm).
• ATEX standards: ATEX standards concern the protection of people working in environments sensitive to explosion risks.
• MIL-STD-810G/F is an American standard that indicates the robustness of the device. This standard was developed for the US military and is now used commercially to indicate to what degree a product is suitable for the environmental conditions.