Electronic Stove Control Sensors Are More Efficient and Safe REED RELAYS REED SENSORS REED SWITCHES Introduction The new stove tops particularly those made of the flameless, burnerless ceran stoves use reed sensors to eliminate the need for knobs and use less power. Gas stoves and electric stoves with their exposed heating elements are always in need of cleaning. With gas stoves there is always the potential of fire as well. Figure 1. MK17-X-3 Sensor physical layout Features • Magnet and Reed Sensor are isolated and have no physical contact by typically having the magnet mounted to a sliding device that is independent of the stove top, and the Reed Sensors are mounted on the under side of the stove top strategically placed such that the magnetic field of magnet will be sensed when brought within their proximity. Figure 2. Magnet assembly is independent of stove and is used to control the burner level. The magnet can be stored out of reach of children when not in use. • The reed switch used in the Reed Sensors is hermetically sealed and is therefore not sensitive to high temperature environments • The magnet is not affected by its environment • Tens of millions of reliable operations • Surface mounting and through hole mounting • Cylindrical hole and screw fastening mounting • Contacts dynamically tested Applications • Ideal for sensing the heat settings for each stove burner replacing the need for costly knobs. • Ideal for applications sensing remotely through any non-ferromagnetic material in a host of different configurations Figure 3. When magnet is inserted into stove top slide and moved over the sensors mounted beneath the Ceran top, the switches are actuated at each burner level. Reed Sensors Allow KnobKnob-less Operation of Stove Tops and Represents a Real ‘Green Approach’ Appliance designers continue to improve stove tops by making them less dangerous, more energy efficient and more child proof by ceran heating elements and knob-less operation by using reed sensors. The ceran stove is also very easy to keep clean with its smooth surface over the entire top. This contrasts with gas stoves that have open flames for heating with reports of several household fires each year. These coupled with the exposed electric elements of electric stoves are in constant need of cleaning. The new ceran stoves use a magnet mounted in a plastic housing that is independent of the stove top. Reed sensors are typically mounted on circuit boards on the underside of the stove top. When the magnet assembly is brought in the vicinity of the reed sensors, the contacts close and a signal is sent to the electronics which turns on the burner to the selected level. Moving the magnet further will select a higher burner level, lower burner level, or turn off the burner when its use is complete. 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 3 www.meder.com Electronic Stove Control Sensors Are More Efficient and Safe REED RELAYS REED SENSORS REED SWITCHES Specifications Defining the MK06 & MK15 Series Operate specs Min Max Units Must close distance 5 25 mm Must open open distance 5 25 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 MK06 Storage Temp MK06 Operate Temp MK15 Storage Temp Temp MK15 Typical 50% Min Max Units 200 0.5 1.5 10 150 200 320 -20 -20 -20 -20 0.5 0.1 85 85 130 130 V Amps Amps Watts mΩ mΩ V msec msec °C °C °C °C Reed sensors represent the most energy efficient approach instead of using hall effect sensors that draw power all the time whether its in the sensing mode or not. The reed sensors while sitting idle draw zero power, and since that is the case 99.9% of the time much energy is saved. Also, children who cannot turn off their inquisitive minds are always intrigued with stove knobs. Usually they will find a way to reach them and turn the knobs. In the past this has led to fires and some badly burned children. With this new approach, this cannot happen, because there are no knobs and the plastic sliding assembly enclosing the magnet can be simply picked up and stored in a convenient location, away from any inquisitive minds. Because MEDER’s sensors use hermetically sealed reed switches that are further packaged in strong high strength plastic, they can be subject to high temperature environments without any loss of reliability. The reed sensor is an excellent choice because it can operate reliably over a wide temperature range, and represents an economical way to carry out the sensing function. MEDER’s sensors are packaged for surface mounting as well as through hole mounting. Also, MEDER has cylinder packages as well as screw fastening packages having lead wires for remote attachment to the electronics. Consult with our engineers for specific details for your exact application. Consider some of the below options in surface mount and through hole versions for meter reading or similar applications. Surface Mount Series Series MK15 MK16 MK17 MK22 MK23MK23-35 MK23MK23-66 Figure 3. MK15 Tape & Reel MK23MK23-87 MK23MK23-90 Dimensions mm W 2.5 H 2.5 L 19.50 W 2.3 H 2.3 L 15.60 W 2.1 H 2.1 L 9.61 W 2.7 H 2.3 L 15.60 W 2.2 H 1.95 L 15.75 W 2.2 H 2.7 L 19.60 W 2.0 H 2.1 L 15.60 W 2.54 H 3.05 L 24.9 Illustration inches 0.098 0.098 0.768 0.091 0.091 0.614 0.083 0.083 0.378 1.060 0.091 0.614 0.087 0.077 0.620 0.087 1.060 0.772 0.079 0.083 0.614 0.100 0.120 0.980 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 3 www.meder.com Electronic Stove Control Sensors Are More Efficient and Safe REED RELAYS REED SENSORS REED SWITCHES Through Hole Series Series MK06MK06-4 MK06MK06-5 MK06MK06-6 MK06MK06-7 Dimensions mm W 3.3 H 3.3 L 12.06 W 2.8 H 3.2 L 14.30 W 3.3 H 4.2 L 17.24 W 3.3 H 4.2 L 19.78 Illustration inches 0.130 0.130 0.475 0.110 0.126 0.563 0.130 0.165 0.679 0.130 0.165 0.779 Cylindrical Panel Mount Series Series MK03 MK03 Dimensions mm Dia 5.25 L 25.5 Illustration inches 0.207 1.004 MK14 MK14 Dia L 4 25.5 0.157 1.004 MK18 MK18 Dia L 5 17 0.197 0.669 MK20/1 MK20/1 Dia L 2.72 10 0.107 0.394 Rectangular Screw Flange Mount Series Series MK04 MK05 MK05 MK12 MK12 Dimensions mm W 13.9 H 5.9 L 23.0 W 19.6 H 6.1 L 23.2 W H L 14.9 6.9 32.0 Illustration inches 0.547 0.232 0.906 0.772 0.240 0.913 0.587 0.272 1.260 **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 3 of 3 www.meder.com