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Showing posts with the label protection

Short circuit protection for almost any power supply

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This instructable is about a universal short circuit protection that I’ve designed to use in bench power supplies. I’ve designed it to fit in most power supplies circuits. In order to this circuit fit in your bench power supply, you will need to do some calculations, but don’t worry, I’ll explain everything on the next steps. [ ]

Restricted earth fault protection connected earth fault relay

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Electronic Fuse for DC Short Circuit Protection

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This is an electronic fuse that protects the load against short circuit. Project Description Relays must be chosen with a voltage value equals to the input voltage. Don’t omit using the 100uF capacitor with appropriate voltage value with respect to the input voltage. If you can’t provide, you can use C106 instead of BRX46. You can adjust the current with using 10K potentiometer. If you will use the fuse with very high currents, lower the 0R6 5W resistor value (ex. 0R47, 0R33, 0R22 or 0R1). Watt value of the resistor should be increased also.

Crowbar Speaker Protection

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Crowbar circuits are so-called because their operation is the equivalent of dropping a crowbar (large steel digging implement) across the terminals. It is only ever used as a last resort, and can only be used where the attached circuit is properly fused or incorporates other protective measures. A crowbar circuit is potentially destructive - if the circuitry only has a minor fault, it will be a major fault by the time a crowbar has done its job. It is not uncommon for the crowbar circuit to be destroyed as well - the purpose is to protect the device(s) attached to the circuit - in this case, a loudspeaker. Description There's really nothing to it. A resistor / capacitor circuit isolates the trigger circuit from normal AC signals. Should there be enough DC to activate the DIAC trigger, the cap is discharged into the gate of the TRIAC, which instantly turns on ... hard. A TRIAC has two basic states, on and off. The in-between state exists, but is so fast that it can be ignored for ...

Temperature protection using PTC and LM393

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 Used as a protective circuit above uses a component named PTC , the components in the operating obstacles , but obstacles desert PTC component is influenced by temperature, whereby if the cold temperatures of less than 100 degrees celcius , then this component has a few obstacles. And when temperature run to 100 degrees celcius or higher, which is owned PTC resistance will rise ass well. Because it depends on ambitient temperature , the PTC can be assembled into a circuit protection if high ambitient temperature, tand automatically switchess off, circuit like a schematic above. Part List : R1___4K7 R2___10K R3___1K9 R4___1M R5___4k7 TH1__PTC thermistor IC____LM393

Protection of the Mosfet in flyback power supply

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PKC-136 PEAK CLAMP CHARACTERISTICS VBR 160Vdc VDRM 700Vdc P 1.5W . See Circuits Diagram below : Protection of the Mosfet in flyback power supply    Feature : - Protection of the Mosfet in flyback power supply -  TRANSIL™ and blocking diode in a single package BENEFITS - Accurate voltage clamping regardless load - Reduced current loop - Reduced EMI emission - High integration - Fast assembly - Reduced losses in stand by mode