Descriptions:Switch Type: NC(normal closed type), the circuit is closed normally, and, that if a magnet not near it, the circuit open. It consists of a pair of contacts on ferrous metal reed in a hermetically sealed glass envelope. There are two types of reed switches: normally open reed switches and normally closed reed switches. In the presence of a magnetic field, the contacts of a normally-open reed switch will close. A normally-closed reed switch is closed when it is not near a magnet; as a magnet is brought close to it, a normally-closed switch will open. .
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Material: Aluminium. 1 X Surface Magnet. Of the 4 available wires, two carry the signal from the switch while the remaining two function as a tamper loop. These are designed for ease of installation with countersunk fixing holes.
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Material: Aluminium. 1 X Surface Magnet. Of the 4 available wires, two carry the signal from the switch while the remaining two function as a tamper loop. These are designed for ease of installation with countersunk fixing holes.
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Description:Suitable to used in apartment, hotel, office, etc.The entry alarm adopts magnetic sensor design to detect any entry from door or window.Easy to install, it will warning you somebody is coming in with loudly and harsh sound.Mounting screws are included here.
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Aluminium magnetic reed switch for alarm systems,  electrical enclosures etc. Suitable for doors and windows on hardwired systems. Normally closed and tamper pairs, no EOL double pole.  New in sealed bags.  10 available. 
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Strong adsorption force, the magnet end is made of strong magnetic potting to make the sensor more sensitive. Alarm Current: 15ma. Sealed design, dustproof and waterproof, even if the door sensor is in the water, the signal will not be interrupted.
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The door contact sensor is a magnetic field electrical switch that provides a high-pitched alarm when someone opens a door or window when it is closed, thus protecting your home.SpecificationColor: GreyMaterial: Zinc AlloySize: Cable Length: 380 mm / 14.96 inchMaximum Current: 0.5AMaximum Voltage: 0-100VSensing Distance: 50-70 mm / 1.97-2.76 inchMagnetic Sensor 1: 10 x 4.8 cm / 3.94 x 1.89 inchMagnetic Sensor 2: 10.6 x 5 cm / 4.17 x 1.97 inchPacking List: 1 x Rolling Door Contact SensorAdvantageRust-proof Material - The wired contact sensor is made of rust-proof and durable zinc alloy, with sensitive response of magnetism and can be used for a long time.
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Enhance your home or office security with our magnetic reed switch. This surface-mounted door and window contact is good for detecting the opening and closing of the door and window. Suitable for use in homes, shops, hotels, computer rooms, and other settings where security is a concern. In addition to providing an extra layer of security, these magnetic reed switches can also be used for automation purposes, such as turning on lights when a door is opened.SpecificationContact Type: Normally Open (NO)Max. Voltage: 100VMax. Current: 0.5AMax. Power: 10WOperating Distance: 10mmDimension: 29mm x 15mm x 9mm/ 1.14-inch x 0.59-inch x 0.35-inch (L*W*H)Packing List: 4 x Sensors, 4 x MagnetsAdvantageThe door magnetic contact is made of ABS material that is durable and long-lasting.
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