Contrinex Inductives🧲 are ‘Hot Stuff’♨️ on Computer🖥️ PCB Soldering Reflow Oven

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Contrinex Extended Distance Inductives🧲 are ‘Hot Stuff’♨️ on Computer🖥️ PCB Soldering Reflow Oven

A manufacturer of computer Printed Circuit Boards (PCBs) uses presence detection immediately after the soldering reflow process, to trigger a subsequent operation. This is achieved by mounting a long-distance Contrinex inductive sensor above the exit conveyor of the reflow oven to detect each motherboard as it passes out of the oven. The customer’s control system accepts the sensor’s output switching to initiate the next process stage – Read more at 500.PLUSAx.co.uk


During the manufacture of PC motherboards, a soldering reflow process is used to secure components on to PCBs. Following assembly, boards are conveyed into a reflow oven, where the temperature increases in a carefully controlled manner in line with a predetermined thermal profile, melting the solder paste on the boards.

As each board leaves the oven, a sensor must trigger the customer’s control system and activate a transfer mechanism, moving the board automatically to the next process stage.

The ambient temperature immediately at the oven’s conveyor output can reach 80°C (176°F), which has caused unacceptable rates of sensor failure in the past. Sensors must therefore operate continuously in this environment with ultra-high reliability.

Extended sensing distances are highly desirable for this application as several types of motherboard, each with different component heights, pass through the oven. Long-distance sensing also allows the sensor to be positioned further from the hot PCBs.



Contrinex 500 Series Extended Sensing Distance Inductive sensors are ideal for this demanding application.  Condist® technology delivers best-in-class operating distances and sensors have a continuous rating to 70°C (158°F). Trials confirmed highly stable performance even in the elevated ambient temperatures around the reflow oven. Vacuum-encapsulated electronics ensure excellent resistance to thermal shock and vibration.

Extra Distance sensors are mounted vertically on steel brackets attached to the exterior of the reflow ovens, and sense the presence of each motherboard as it passes beneath the sensing face. The operating distance is set at 10mm, eliminating the risk of collision with components on the board, and an M12-threaded metal housing allows easy positional adjustment when necessary.

As is typically the case with Contrinex sensors, IO-Link connectivity is included as well as the choice of an industry-standard PNP or NPN interface to the customer’s control system. No additional electrical or mechanical protection is required in spite of the adverse operating conditions.

Previously, sensors from other manufacturers did not detect boards reliably and had unacceptably short service lives, causing frequent interruptions to production. Sensor replacement costs were excessive. Contrinex inductive sensors have been reliable and long-lived, providing a professional sensing solution with an attractive total cost of ownership.

PLUS Automation aims to help you #MakeSenseofSensors, helping solve applications, improve machine performance and reliability, and reduce costs using Contrinex’s exceptional choice of sensors. Find more information and read other application examples go to www.PLUSAx.co.uk



🕵🏽‍Reliable & fast detection

3️⃣Triple the normal sensing distance

📏22mm sensing range – M18 sensor

💪Robust and & reliable in demanding conditions

🎛️IO-Link – Ideal for Industry 4

🌡️ -25°C to +70°C

💰Low-cost solution



Find out more at 500.PLUSAx.co.uk, or Click to download a flyer, or Click to download Contrinex’s Product Overview brochure

PLUS Automation aims to help you #MAKESENSEOFSENSORShelping solve applications, improve machine performance and reliability, and reduce costs using Contrinex’s exceptional choice of sensors.

Find more information and read other application examples go to www.PLUSAx.co.uk

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