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Sender: "piclist-bounces@mit.edu" Date: Mon, 20 Jan 2020 22:05:07 -0800 Subject: Re: [EE] Diode bridge failure Thread-Topic: [EE] Diode bridge failure Thread-Index: AdXQJ8XEJHXXvZ1qSb++6b0iInnuwg== Message-ID: <9bb6fb65d87562c6df9183be88476a52.squirrel@mai.hallikainen.org> References: List-Help: List-Subscribe: , List-Unsubscribe: , In-Reply-To: Reply-To: Microcontroller discussion list - Public. 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I had a situation where a device had a bridge made with 400PIV diodes. It was powered by an external 24VAC transformer. The diodes would occasionally fail. These were used in movie theaters and a spike of several hundred volts to ground would appear on the transformer secondary (common mode, not differential) when a xenon lamp in a projector was struck. This would occasionally blow the diodes. Recognizing you have an MOV there to suppress such transients, but I wonder if enough of the transient could still get to the diodes. Harold --=20 FCC Rules Updated Daily at http://www.hallikainen.com Not sent from an iPhone. --=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 .