Electricity and Control May 2025

Sensors + switches: Products + services

Infrared visioning in automotive end-of-line testing

temperature on the heated window surface exceeds or falls below a specific value (say, 35°C), the camera sends an analogue signal to an alarm LED, which is easily visible to the specialist at the certification station in the automotive production facility. Furthermore, the process can be fully automated, with follow up actions (such as switching o” the process) triggered by the Optris system. This automation shortens production time without disrupting the process flow. Streamlining automotive production For the customer, the benefits of using Optris IR devices are clear: the measurement process has been reduced from up to 15 minutes to around 30 seconds, and technicians are free to perform other tasks. The time saving and e”iciency gains are significant advantages, with cost savings that support using the PI 640i. The PI 640i thermal camera also o”ers advantages in other thermally related production processes. Its high thermal sensitivity allows for quick detection of seat temperature changes, increasing time savings on the production line. The instrument can also capture radiometric video at frame rates of 32 Hz and up to 125 Hz in subframe mode, enabling accurate monitoring and analysis of rapid temperature changes and dynamic processes. The camera is equipped with interchangeable lenses that cover di”erent fields of view (15°, 33°, 60°, and 90°), so it can adapt to various printer sizes and applications by selecting the optimal focus and field of view. It is robust and designed for industrial environments, with an IP67 rating that protects against dust and water ingress. It can operate in temperatures ranging from 0°C to 50°C, and separate accessories are available to enhance its durability further. This ensures reliability and longevity under demanding conditions. Various interfaces and a comprehensive soŽware package facilitate integration into existing systems. The camera can be connected via USB 2.0 or, optionally, via a Gigabit Ethernet (PoE) interface. The included Optris PI Connect soŽware package enables simple setup and remote monitoring of the camera. Additionally, the camera o”ers several industrial process interfaces, including analogue and digital inputs and outputs, and relays for alarm and fail-safe functions.

Window defrosters are an important feature in vehicles, particularly in colder climates. They help defrost ice from the windowpanes to ensure drivers can maintain visibility and safety. The manufacturing process begins with producing windowpanes made from special laminated glass. Thin, nearly invisible heating wires of electrically conductive material are integrated into the panes. The wires are methodically embedded in the glass to ensure even heat distribution and e”icient heating performance. For the rear windshield’s heat conductors, the defroster operates by sending an electrical current through a grid made of metal and resin, which is attached to the surface of the glass using an adhesive. As the defroster resists the flow of electricity, it converts the electrical energy into heat, warming the glass windowpane. Issues with the defroster are common because the wiring is typically thin and fragile, so it is susceptible to breakage. On the production line, automotive manufacturers need an e”icient solution to measure the temperature of the windows quickly and precisely, ensuring that the connections, installed cables, and wires work correctly and do not have any defects, before a vehicle is released. Previously, the end-of-line test procedure was performed manually by technicians. Heating the elements took 10 to 15 minutes. In this application case, the manufacturer sought to speed up and automate this process as much as possible. Automating quality tests The Optris PI 640i thermal imaging camera, available locally from Instrotech, provides a solution. This compact VGA camera (640 x 480 pixels) with a high thermal sensitivity of 40 mK, detects and evaluates even minor temperature di”erences. The PI 640i can be installed at any distance from the measurement object within the system and deliver the necessary signals to any location (peripheral devices), allowing operators to focus on other processes simultaneously. During the final test, the electrical connection of the heating strips is first examined by applying a defined voltage and measuring the current flow to ensure all wires function correctly without interruptions. Next, the defrosters are tested in a simulated environment to check their performance under simulated real world conditions. This involves deliberately misting the windows and activating the heaters to observe how quickly and evenly visibility is restored. Additionally, the window defrosters are tested for durability by repeatedly switching them on and o” to ensure reliable performance through multiple cycles. The PI 640i IR camera records every thermal change in real-time and monitors the entire process. If, for instance, the The OPTRIS PI 640i thermal camera is recommended for e˜icient automated end-of-line testing of car window heater defrosting systems in automotive manufacturing.

For more information visit: www.instrotech.co.za

Using infrared visioning and temperature measurement technology for faster testing in automotive manufacturing.

22 Electricity + Control MAY 2025