A reed relay is a lot like a standard relay – it can be used as an electronically controlled switch. While a standard relay has a solenoid with a mechanical armature that moves a contact, a reed relay uses magnetic force to move the contact. A small electromagnet is housed next to the contacts; when power is applied, the contacts are closed. Because these relays do not have a mechanical armature, these relays can be actuated much quicker than their mechanical counterparts.

So why use a Reed relay over a conventional relay or transistor? Since Reed Relays are sealed in a vacuum they are able to use contacts made from Silver. Silver has a very low resistance which makes these ideal for switching extremely low voltages and current.

This specific reed relay can switch voltages up to 200VAC / 200VDC at a half amp (500mA). The coil is rated at 5VDC and requires 10mA.