It is crucial to use pneumatic sensors for precise pressure monitoring in various robot and industrial control applications. To ensure reliable operation, pressure monitors must have excellent resistance to overpressure and vacuum, and should include a measurement unit that is insensitive to liquids or deposits.
In addition to precise and robust work, application flexibility is also a key feature that can accelerate initial installation and support configuration changes, enabling mass customization in Industry 4.0.
The monitor should include an easy to read display screen for quick status checks, programmable outputs for alarms, and local settings and operations using integrated buttons. IO Link is required for digital data transmission to achieve remote process monitoring and configuration. In some devices, analog output is more useful.
Supports multiple installation configurations to ensure compatibility with various system designs.
This article introduces the PQ series precision pressure monitors of ifm Efector (ifm) and details how they meet the different needs of pneumatic and compressed air systems in various industrial and robotic applications.
user interface
The visual interface is a major feature of the PQ series. It includes a 1-inch color TFT display screen, switch point LED indicator lights, and switches for changing display and setting parameters. The main process value measured is pressure, which can be displayed in various units including bar, psi, or kPa. Vacuum degree can also be expressed as a percentage of the set point.
The display screen can show the configuration set point (SP) and reset point (rP) of the digital output. The switch point uses LED as an indicator light. For models with analog output, the display screen can be used to set and display the analog starting point (such as 4 mA) and ending point (such as 20 mA) to scale the signal. The user interface includes the following elements (Figure 1):
If output 1 activity, the switch status LED will light up
If outputting 2 activities, the switch status LED will light up
TFT display screen elements:
Device Status
Process value. The display screen can switch from standard color (green) to another color (red), and when the process value enters or exceeds an acceptable range, the color will switch, making it clear at a glance.
Diagnostic and performance information, such as switch frequency, recorded minimum or maximum pressure. In Figure 2, Hi. P represents the highest measured value of pressure.
Button for displaying configuration and parameter settings
IFM PQ series user interface layout image
Figure 1: PQ series user interface layout. (Image source: ifm)
The PQ series has models with and without configurable analog outputs. The PQS model (such as PQS812) has two digital outputs, while the PQC model (such as PQC812) has a configurable analog output in addition to the two digital outputs. The analog output of PQC model can be used to send proportional signals.
Mechanical and automation designers can choose equipment with specific measurement ranges. The measurement range of PQS812 and PQC812 is -1 bar to 10 bar (-100 kPa to 1000 kPa, -14.5 psi to 145 psi). The PQS816 and PQC816 models are designed for low-pressure and vacuum applications, with a measurement range of -1 to 1 bar (-100 to 100 kPa, -14.5 to 14.5 psi). Applications that only require vacuum measurement can use PQS819 and PQC819, with a measurement range of -1 bar to 0 bar (-100 kPa to 0 kPa, -14.5 psi to 0 psi).
Compressed air treatment is a common operation in pneumatic systems. This is a process of removing impurities (such as moisture, oil, and dust) from compressed air, with the aim of protecting pneumatic equipment, ensuring system reliability, and maintaining product quality.
The PQ series is particularly suitable for compressed air treatment systems, as coated and sealed silicon measuring units can maintain performance when the air is contaminated with water, dust, or oil.
Vacuum grasping application is a common use of PQ series pressure sensors. These applications may include multiple pick actuators. The red/green color change on the display screen allows the operator to clearly see the process value of each pickup at a glance (Figure 2).