What is the Function of the Reed Switch in a Telephone Hook?
Whether you are looking to use the reed switch for a telephone handset hook or in any other application, it's important to know exactly what its function is. A reed switch is a type of switch that is used in proximity and sensing applications. When the switch is activated, it sends a signal to the receiver. You can also use the reed switch in other ways, such as as a relay switch.
Reed switches are used in proximity and sensing applications
Unlike normal switches, reed switches work as both an electrical bridge and a magnetic switch. This makes them suitable for use in proximity and sensing applications. They are also liquid resistant and suitable for use in dirty environments.
Reed switches are encased in small glass tube-like envelopes. When the glass envelopes are moved together, they become magnetized. These glass envelopes then become the contacts for the reed switch.
The reed switch detects changes in the magnetic field and controls the flow of electrical currents in a circuit. The switch can be used in proximity sensors and alarm systems. Reed switches can also be used in laptops. In laptops, the switch is triggered when the screen is lowered.
Reed switches are found in many electronic devices, including automobiles and fluid control systems. They also are used in flip style cellphones. These cellphones have a magnet in the upper part of the case. When the reed switch is closed, the magnet swings close to the switch. When the reed switch is opened, the magnet springs back to its original position.
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They can also be used in other ways
Typically, the most obvious use of a reed switch is to detect intruders. This is often done in the form of intruder alarms. But, you can also use these switches in other applications.
For example, you can use a reed switch to determine if the water in your electric shower is too hot. The switch works by opening and closing the bridge. When the bridge is open, the magnet on the door can be used to trigger the switch.
Another cool use of a reed switch involves a magic wand. In fact, Jason Poel Smith's magic wand uses a reed switch.
It uses a small electric motor to swivel the head. The switch is encapsulated in a sealed glass envelope. Its contacts are about ten times thinner than the human hair.
Other uses for a reed switch include measuring wind speed. Anemometers with rotating cups contain reed switches inside to sense the wind speed.
Ensure reed contacts are only control contacts for direct or indirect relay control
Ensure reed contacts are only control contacts for direct or indirect relay control. An electrical switch is a device that switches an electrical circuit. The circuit is arranged to provide energising and discharging current to the circuit. Normally, the circuit will consist of two contact sets, one of which is closed in the de-energised position of the relay and the other which is open.
Reed switch contacts are very small and may fail if they are subjected to overload. They may also fail if a shock occurs. To prevent this, the contacts should be fitted with a safety circuit monitor. A safety circuit monitor will ensure that the contacts are switched only with a current that is safe.
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Reed contacts should be able to switch a voltage of at least 500V. This is because relay coils are "highly inductive loads". When de-energised, these loads generate large reverse emfs. This is why manufacturers require arc suppression in their relays.