Not all photoelectric sensors in industrial environments are accurate including photoelectric sensors on production lines, in factory processes, construction, and mining sites and in other industrial environments. Inadequate sensors can cause unnecessary downtime and cost companies profit and reputation.
The key problems with many photoelectric sensors are that they have inadequate background suppression. This means that the sensors cannot detect a target close to a reflective background. Other key problems with some sensors include that they do not have colour independent detection, cannot detect lustrous surfaces and cannot detect objects at oblique angles.
Inadequate background suppression and colour-independent detection
Photoelectric sensors that have poor background suppression cannot prevent background light and objects affecting incorrect detection. For example, if the sensor is in use on a distribution warehouse conveyor belt, it may be confused by the metallic shine from the conveyor. If the sensor stops the conveyor working due to incorrectly detecting the metallic shine, deadlines for delivery of product and output can be missed due to unnecessary downtime.
Non-detection of lustrous surfaces
Another problem with some photoelectric sensors is that they cannot detect lustrous surfaces. Lustrous surfaces are very shiny surfaces. For example, sensors in the production of sheet metal may not be able to detect the metal pieces going down the conveyor belt if they are too bright. The shine from shiny surfaces can disrupt the sensor’s detection performance and affect the plant’s operation and its ability to perform its function in the supply chain.
Non-detection of objects and light at oblique angles
Some photoelectric sensors cannot detect objects at obtuse or acute angles. If a sensor cannot detect objects at oblique angles, it can be disadvantageous to the production process. For example, in the detection of cylindrical objects. If the sensor is not correctly mounted and aligned during installation – or bumped slightly out of alignment after installation – the sensor will unreliably detect the object creating problems within the process.
The Solution – IFM’s new PMDLine of photoelectric sensors
IFM’s new PMD line of photoelectric sensors addresses all three concerns described above and has precise detection of products with a switch point up to 2m. The secret is in its patented PMD technology which is based on Time-of-Flight (ToF) technology.
The OID and O5D type photoelectric sensors has reliable background suppression and colour-independent detection. The OID has a simple switch point setting by rotatable setting ring with integrated locking function whereas the O5D has two pushbuttons and a LED display.
The PMD line photoelectric sensors feature reliable detection regardless of whether the object is a shiny, matt, dark or light object of any colour. The unit allows any angle of incidence and thus flexible mounting positions are possible. This simplifies installation and saves costs.
All PMD line photoelectric sensors have background suppression, a visible laser light, a measuring range of 0.03m to 2m and background suppression up to 20m. The sensors have 2 switching outputs, overload protection, switching frequency of 11Hz, operating voltage of 10…30VDC and a life expectancy of 50,000 hours. The laser beam can be switched off via IO Link or pin 5 on the M12 connector.
The new OID204 has an IP69K rated stainless steel body for those areas that have high wash down requirements. The IP69K version of the OID photoelectric sensor is set-up via IO-Link and does not have the setting ring to enable it to conform to the IP69K ratings.
ifm’s exceptionally large product portfolio does not only cover all relevant standard solutions but also the special requirements of individual industries. In addition to position and process sensors, sensors for motion control and safety technology are part of the product range. Furthermore, ifm offers products for industrial imaging and communication as well as identification systems and systems for mobile machines including high IP, shock-resistant and temperature rated controllers and displays.
With I/O Link, you can integrate directly into your local control systems and with this connectivity, the sensor information can be utilised up to ERP level.
For more information on IFM’s new range of OID sensors, click here