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Sender: "piclist-bounces@mit.edu" Date: Sat, 18 Jan 2020 13:26:47 -0800 Subject: [EE] Magnetic lock Thread-Topic: [EE] Magnetic lock Thread-Index: AdXOR6Vg4ewWn8KRTfWmCEirNiirVg== Message-ID: List-Help: List-Subscribe: , List-Unsubscribe: , Reply-To: Microcontroller discussion list - Public. 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The lock consists of an armature plate which bolts to the door and an electromagnet which, when energised, grabs the armature with a force of several hundred pounds. I splashed out an extra fiver for the "monitored" version which lights an LED anf operates a relay when the device detects that the armature is held by the magnet. But how does it detect the locked condition? Does the current in the magnet increase when something is attracted by it? Or what? __________________________________________ David C Brown 43 Bings Road Whaley Bridge High Peak Phone: 01663 733236 Derbyshire eMail: dcb.home@gmail.com SK23 7ND web: www.bings-knowle.co.uk/dcb *Sent from my etch-a-sketch* --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .