Protection of Electrical Devices with Diodes

Protection of Electrical Devices with DiodesOh, buggers.. This is what we usually say when our new, correctly assembled and fully operable device dies at the first connection, even before it had time to work. Such failures are often a result of polarity reversal.In reality, such situations are really easy to avoid - all you need to do is modify your circuit by a regular semiconductor diode at the point of power input. This measure will help you forget that incorrect polarity could lead to any sad results.I would like to also emphasize the danger of connecting a battery to the battery charger without following the polarity. In doing so, you short circuit the battery, and such short circuit current (and in lead batteries it could be hundreds of Amperes we are talking about) flows through the rectifier, which heats up and then inevitably fails. And in this case once again, connection of a power diode to one of the battery charger's wires will help avoid such and accident and would not stand in the way of operation.In many cases devices are protected against excessive voltage with the help of fuse diodes. In the event of reversal of polarity, such diodes appear to be connected in the forward direction and they protect the device itself, but do cause a short circuit within the circuit. This is bad in itself, but it also leads to the diodes significantly heating up and failing a lot more often. This scenario is also typical of most KREN voltage stabilizers. After the said devices fail, they no longer provide any protection against reversal of polarity with respect to the rest of the circuit. If it is impossible to install such protection on the entire circuit, you can protect the most expensive elements, for example microcontrollers and signaling processors, by adding a diode to the power outputs.This small trick will help you save lots of time, money and nerves.

Category:

Science & Technology

Tags:

• circuitry
• diode
• polarity
• polarity reversal
• protection