Protection Circuit | Electronic Project Circuits

Posts Tagged ‘protection circuit’

Over voltage and low voltage protection circuit

This is an electrical circuit protection device sound disappeared, when too much voltage 220V, and protection, when pressure is too low with Using the relay cut off power when voltage problems.
From the circuit when the voltage is 220 volts AC through a transformer T1. It serves to reduce the pressure remaining 12 volts, through a D1-D4 connected to Direct rectifier bridge circuit. To convert the voltage, alternating current to direct current. Then, through the C1 and C2 to the power filter smoothing. And entering a pin. Or input pin of IC1, a loan IC Rex bit computing to 12-volt power supply is fixed to the IC2. That it is IC Op Amp. Pressure acts edge IC2/1 High Voltage Detector, High Voltage ICs, if this current work to the Q1 and relay function, it works with, thus cutting off power from the load instantly. The IC2/2 serves to detect the lower voltage. The two components can be specified by VR1, VR2. LED1 display when power or low power over a specified.

Be the first to comment - What do you think? Posted by admin - December 14, 2010 at 7:35 am

Categories: Detector, Electronic Control, Power supply Tags: Low voltage protection circuit, Over voltage protection circuit, protection circuit

Alarm when the supply to rack with 1N4001

To use such circuits.If you have identified the polarity of the power supply or power supply connector on the wafer is not clear.The wrong polarity can cause damage and range.But when using this circuit with active circuit, it can be Protect And show a correct polarity.
Operation of the circuit is not complicated. When the supply terminals to make LED1, D1 has been bias direct. It makes LED1 light, and The piezo speaker PZ1 emit noise.The lamp LED1,it would be R1, assist current limiting and voltage.To prevent LED1, no damage.But if the supply polarity is LED1, D1 will be actuated bias. D1 is not bias the LED1 is not lit.And piezo speaker PZ1 not emit noise. The D2 works, The D2 works, because it was direct bias.Make a power supply circuit as usual.

Be the first to comment - What do you think? Posted by admin - September 16, 2010 at 6:45 am

Categories: Alarm systems, Detector Tags: 1N4001, polarity protection, protection circuit

24VDC Motor Speed Control with 20A Shot Circuit Protection

This be Motor Speed Control Circuit 24 Volt at current 20Amp. By it uses IC SG3526Bcontrol in the character PWM that receive like very much and drive motor with power Mosfet number IRFP7410 x 2 pcs. Then can apply to DC Motor at use 20 Amp get comfortablely and still have Shot Circuit Protection circuit As well. You see the detail adds at picture circuit.
source : aircraftdesigner