HandsHands-Free Barcode Scanner Scanner Sensor REED RELAYS REED SENSORS REED SWITCHES Introduction Most major food chains and retail stores process purchased items through their payment stations using electronic automatic barcode scanners. Most of these barcode scanners are equipped with a hands-free docking cradle. A Reed Sensor and magnet used in tandem, with the hand-held barcode scanner and docking cradle, allowing hands-free scanning mode, provide the most reliable results. Figure 1. MK23 Sensor physical layout Features • Hermetically sealed Figure 2. Hand-held barcode scanner and docking cradle in the hands-free mode. • Dynamically tested contacts • Reliable switching • Ability to activate and control the on and off points over large distances • Millions of switching operations Applications • Sensing for barcode scanners in hands-free mode • Sensing long distances when using devices requiring a docking cradle Figure 3. Barcode scanner is out of docking station, deactivating the Reed Sensor and switching off the hands-free mode MEDER’s MK23MK23-35 Reed Sensor Sensor Solves A Major Reliability Problem Hand-held barcode scanners have become the norm in processing retail goods. They can automatically adjust inventory levels and improved operating costs. Many stores have even eliminated the sales clerk and allow customers to process their own purchases. Because hand-held barcode scanners are portable, they can see high shock and vibration forces in their normal use, especially when dropped on hard surfaces. Some mechanical switches and some Reed Switches are particularly sensitive to vibration and shock. So much so, that their actuate points can shift when dropped making them malfunction in the barcode scanner. Of course when this occurs there is inevitably a busy line of customers waiting for their purchases to be processed. MEDER’s MK23-35 Reed Sensor is not susceptible to shock and vibrations forces. However, several of MEDER’s Reed Sensors were tested in authentic hand-held barcode scanners, in which they were dropped repeatedly from a height of 4 feet in all six axes, at various temperatures, with no failures and no significant changes to any of their specifications. Failures were reported in other types of sensors tested along side MEDER’s Reed Sensors. A full report is available upon request. MEDER electronic Application MEDER electronic AG | Germany | tel.: +49(0)7731/8399-0 | Email: [email protected] MEDER electronic Inc. | USA | tel.: +1 508.295.0771 | Email: [email protected] Page 1 of 2 www.meder.com HandsHands-Free Barcode Scanner Scanner Sensor REED RELAYS REED SENSORS REED SWITCHES Specifications (@ 20° 20°C) MK23 23MK 23-35 Series Operate specs Min Max Units Must close distance 3.3 5.7 Must open distance 4.3 12.2 mm mm Hysteresis Load Characteristics Switching voltage Switching current Carry current Contact rating Static Contact resistance Dynamic contact resistance Breakdown voltage Operate time Release time Operate Temp Storage Temp Min Max Units 200 1.0 1.5 20 150 200 320 0.5 0.1 -20 130 -55 130 V Amps Amps Watts mΩ mΩ V msec msec °C °C Figure 4. Hand-held barcode scanner dropped in 6 axes during shock testing. Consider some of the below surface mount options for this application. Surface Mount Series Series Series Figure 5. MK23 Tape & Reel Dimensions Illustration mm inches MK15 W 2.5 0.098 H 2.5 0.098 L 19.50 0.768 MK16 W 2.3 0.091 H 2.3 0.091 L 15.60 0.614 MK17 W 2.1 0.083 H 2.1 0.083 L 9.61 0.378 MK22 W 2.7 1.060 H 2.3 0.091 L 15.60 0.614 MK23W MK23-35 2.2 0.087 H 1.95 0.077 L 15.75 0.620 MK23W MK23-66 2.2 0.087 H 2.7 1.060 L 19.60 0.772 MK23W MK23-80 2.0 0.079 H 2.1 0.083 L 13.00 0.512 MK23W MK23-87 2.0 0.079 H 2.1 0.083 L 15.60 0.614 **Consult the factory for more options not listed above. ** MEDER electronic Application MEDER electronic AG | Germany | tel.: +49(0)7731/8399-0 | Email: [email protected] MEDER electronic Inc. | USA | tel.: +1 508.295.0771 | Email: [email protected] Page 2 of 2 www.meder.com