Power Indicator | Electronic Project Circuits

Posts Tagged ‘power indicator’

LED Display for On-Off battery indicator

This circuit uses LED – 2 pcs. show something On – Off of or the circuit that use Battery. By LED – D1 flasher , when open and D2 flasher when open. While open that have charge current amount of flow through D1 go to Charge Capacitors 1000 uF , make D1 stick or shine and switch off when Capacitors the full. Then have current which flow be Leakage Current the a little. When enough close capacitors 1000 uF discharge way D2 , then stick tell close or cut the circuit has already. The detail is other , friends see in the circuit yes.

Be the first to comment - What do you think? Posted by admin - November 25, 2008 at 8:09 am

Categories: Battery, Detector, LED Flasher Tags: battery tester, led display, led voltage indicator, power indicator

Blown Fuse indicator LED Display

A Fuse be the equipment protects that use often most. Because of cheapness can use protect electronics expensive circuit. Generally when fuse torn us can know immediately. but in sometimes Fuse torn already we don’t know. such as in electricity automobile system brake system , the system delays the electric current very much, etc. Fuse torn get into trouble at we must know for immediately the safety. I then beg for to advise the circuit is simple. It is can show with , LED that now. Fuse torn already please. See the illustration by equipment value that show that note for Voltage Source 12V , but if friends want to apply to the level Volt the other. As a result change value R1 and R2 get by can calculate from R1 = (Vin – 2) x 50 and R2 = (Vin – 2) x 10000/2 . Think the work of the circuit has a little, It may help to give friends comfortably go up please sir.

Be the first to comment - What do you think? Posted by admin - September 12, 2008 at 7:58 am

Categories: Detector, Electronic Control, Security Tags: led display sign, led voltage indicator, power indicator, protection power supply

Supply Voltage Indicator

A novel supply voltage monitor which uses a LED to show the status of a power supply.

Notes:
This simple and slightly odd circuit can clearly show the level of the supply voltage (in a larger device): as long as the indicator has good 12 volts at its input, LED1 gives steady, uninterrupted (for the naked eye) yellow light. If the input voltage falls below 11 V, LED1 will start to blink and the blinking will just get slower and slower if the voltage drops further – giving very clear and intuitive representation of the supply’s status. The blinking will stop and LED1 will finally go out at a little below 9 volts.

On the other hand, if the input voltage rises to 13 V, LED2 will start to glow, getting at almost full power at 14 V.

The characteristic voltages can be adjusted primarily by adjusting the values of R1 and R4.

The base-emitter diode of T2 basically just stands in for a zener diode. The emitter-collector path of T1 is inversely polarized and if the input voltage is high enough – T1 will cause oscillations and the frequency will be proportional to the input voltage. The relaxation oscillator ceases cycling when the input voltage gets so low that it no longer can cause breakdown along the emitter-collector path.

Not all small NPN transistors show this kind of behavior when inversely polarized in a similar manner, but many do. BC337-40 can start oscillations at a relatively low voltage, other types generally require a volt or two more. If experimenting, be careful not to punch a hole through the device under test: they oscillate at 9-12 V or not at all.

Circuit : Miroslav Adzic – Serbia & Montenegro
Source :: http://www.zen22142.zen.co.uk/Circuits/Power/svind.htm