Wiring Schematic diagram: light

Showing posts with label light. Show all posts

Wednesday, November 19, 2014

Simple LED Emergency Light Circuit

This LED emergency light project is simple, cheap and easy to build. The circuit do the charging of the battery and when the main source is not available such as in brownouts, the white LEDs automatically turn on.

Initially, the voltage output from 220V to 12V converter is fed to the input of LM317 regulator. Then this voltage is regulated down to 7.37V using 240 ohms and 1.2K resistor combination (see LM317 Calculator).

At this instant, the battery is in charging mode and the transistor Q1 is off. Indicator LED serves two purpose, one primarily is to give us idea that the battery is charging and another is to ensure that the Q1 is off.

During brownouts, the transistor Q1 is on and delivers current to 16 white LED of about 20mA each, thus a fully charged battery (6V/4.5Ah) can last up to 14 hours.

The charger has no built in over-current control but still it protects the battery from overcharging since the charging voltage is set only to 7.4V.

Project materials:
1pc - transformer - 220V to 12V-0-12V , center tap 12VA
16pc - 120 ohms resistor 1/4 W
16pc - white LED min 3V@30mA
1pc - red LED
1pc - 1000uF/25V electrolytic capacitor
3pc - 1N4001 diode
1pc - LM317 regulator
1pc - 1.5K resistor 1/4W
1pc - 240 ohms resistor 1/4W
1pc - 1.2k resistor 1/4W
1pc - 9012 pnp transistor or any of much higher capacity
1pc - 6V 4.5ah battery

Thursday, October 30, 2014

Emergency Light Flashlight

3 in 1 - LED Night Light, LED Emergency Light and LED Flashlight; Length: 4.0". The Night Light has an Automatic Sensor which allows On at Dusk and Off at Dawn. The Emergency Light features an 8 Hour Battery Back Up. Convenient White Light Flashlight.

The light is not terribly sharp-witted but its first-class sufficient to facilitate you wont be real bumping into furniture all through a power outage. The light is by the side of its brightest at what time the power is rotten.
When its used having the status of a nightlight it is a not much dimmer but still upbeat adequate to perceive your way around.

The intensity of the light motivation vary depending on how dark the opportunity is. during the belatedly afternoon while the sun is still outside it will live very dim but will perk up up being the extent becomes darker. Although here is a photo sensor on the light a loss of power preference aim the light on in spite of of how dark before light the area is.

The light stays on a bunch longer than the circular emergency plug concerning illumination with the aim of Ive used in the older and it looks a lot better than them. I carry out think it would look even better devoid of the flashlight part of the light and I would have a preference to grasp a version like with the aim of if theyd offer it.

Once plugging into a lookalike outlet it still leaves area intended for a lesser plug to progress into the outlet then to it.

Friday, October 24, 2014

Triac Light Switch as a dimers

The series of light switches this time slightly different from the voltage of work. The series of light switches can work directly on the AC power network. Light switches are using the main component of TRIAC and LDR. The circuit is very simple and the components were sold in the market.

If you want a light reception sensitivity of this circuit can be arranged then the 3.3 MOhm resistor can be replaced with a variable resistor. For more details can be seen from the following series of images.

Circuit Diagram

With Triac Light Switch series is as dimers, but dimers control performed by the reception of light around the LDR. The lower the intensity cayaha received LDR then bright lights. For installation LDR need to be considered so as not exposed to light from the lamp directly.

Thursday, October 16, 2014

Simple Rear Light After Glow Circuit Diagram

This article is of interest only to readers whose bicycle lights are powered by a dynamo. The laws on bicycle lights in the United Kingdom are stricter than in other countries and a dynamo is, therefore, a rarity in this country. From the point of view of traffic safety it is advisable (in UK obligatory) for cyclists to have the rear lamp of their bicycle to light even when they are at standstill. In principle, it is not very difficult to modify the existing rear light with afterglow: all this needs is a large enough energy reservoir. Since the after-glow is required for short periods of time only, a battery is not required: a large value capacitor, say, 1 F, is quite sufficient.

As the circuit diagram shows, in the present circuit, the normal rear light bulb is replaced by two series-connected bright LEDs, D2 and D3. These are clearly visible with a current of only 6 mA (compared with 50 mA of the bulb). The current is set with series resistor R1. The LEDs are shunted by the 1 F capacitor, C1. Since the working voltage of this component is only 5.5 V, it is, in spite of its high value, physically small. An effective regulator is needed to limit the dynamo voltage adequately. Normal regulators cannot be used here, since they do not work at low voltages. Moreover, such a device would discharge the capacitor when the cycle is at standstill.

Rear Light After Glow Circuit Diagram

Fortunately, there is a low-drop type that meets the present requirements nicely: the Type LP2950CZ5.0. Of course, the dynamo output voltage needs to be rectified before it can be applied to the regulator. In the present circuit, this is effected by half-wave rectifier D1 and buffer capacitor C2. Diode D1 is a Schottky type to keep any losses low – important for this application, because the ground connection via the bicycle frame usually causes some losses as well. The value of buffer capacitor has been chosen well above requirements to ensure that C1 is charged during the negative half cycles of the dynamo voltage.

Thursday, September 11, 2014

LIGHT ALARMS

LIGHT ALARM - 1
This schema operates when lightweight|the sunshine} Dependent Resistor receives light. When no lightweight falls on the LDR, its resistance is high and also the transistor driving the speaker isnt turned on. When lightweight falls on the LDR its resistance decreases and also the collector of the second transistor falls. This turns off the primary transistor slightly via the second 100n and also the initial 100n puts a further spike into the bottom of the second transistor. This continues till the second transistor is turned on as onerous because it will go. the primary 100n is currently nearly charged and it cannot keep the second transistor turned on. The second transistor starts to turn off and each transistors swap conditions to provide the second half of the cycle.

LIGHT ALARM - 2

This schema is comparable to lightweight Alarm -1 however produces a louder output as a result of the speaker being connected directly to the schema. The schema is essentially a high-gain amplifier thats turned on initially by the LDR and then the 10n keeps the schema turning on till it will activate no more. The schema then starts to show off and eventually turns off utterly. the present through the LDR starts the cycle once more.

LIGHT ALARM - 3 (MOVEMENT DETECTOR)

This schema is extremely sensitive and may be placed in a very space to detect the movement of a person up to a pair of metres from the unit.

The schema is essentially a high-gain amplifier (made of the primary 3 transistors) that is turned on by the LDR or photo Darlington transistor. The third transistor charges the 100u via a diode and this delivers turn-on voltage for the oscillator. The LDR has equal sensitivity to the photo transistor during this schema.

Streampowers

Wednesday, September 10, 2014

Knight Rider Light Circuit With 6 LEDs

Most of you ask about 6 LED bulbs Knight Rider schema.So Here it is.You can attach this one for your car or van.Actually this is so attractive schema.and This schema operates with 6v.

Note

#IC 40017 data

Friday, September 5, 2014

UV Torch Light

UV (ultra-violet) LEDs can produce eye-catching effects when their light is allowed to interfere with certain colours, particularly with reflected light under near-dark conditions. Also try shining some UV light on a diamond.

Circuit diagram :

UV Torch Light Circuit Diagram

Most UV LEDs require about 3.6 V (the ‘blue’ diode voltage) to light. Here, a MAX761 step-up switching IC is used to provide constant current to bias the UV diode. The IC employs PWM in high-cur-rent mode and automatically changes to PFM mode in low or medium power mode to save (battery) power. To allow it to be used with two AA cells, the MAX761 is configured in bootstrapped mode with voltage-adjustable feedback. Up to four cells may be used to power the schema but they may add more weight than you would like for a torchlight.

To prolong the switch life, R1 is connected to the IC’s SHDN (shutdown) pin. Less than 50 nA will be measured in shutdown mode. Electrolytic capacitor C1 is used to decouple the schema supply voltage. With-out it, ripple and noise may cause instability. The one inductor in the schema, L1, may have any value between about 10 and 50 µH. It stores current in its magnetic field while the MOSFET inside the MAX761 is switched. A toroid inductor is preferred in this position as it will guarantee low stray radiation. D1 has to be a relatively fast diode so don’t be tempted to use an 1N400x because it has a too slow recovery time.

The schema efficiency was measured at about 70%. R2, the resistor on the feed-back pin of the MAX761 effectively determines the amount of constant current, I, sent through the UV LEDs, as follows: R2 = 1.5 / I

where I will be between 2 mA and 35 mA.

Zener diode D4 clamps the output voltage when the load is disconnected, which may happen when one of the UV LEDs breaks down. Without a load, the MAX761 will switch L1 right up to the boost voltage and so destroy itself.

Author : Myo Min

Saturday, August 23, 2014

12v Light Dark Switch

Often, for certain low voltage lighting systems; you would like to turn off the lights during the bright light of the day. Most commercial day/night switches are designed for AC lighting. This hobby schema below was designed for a 12v DC system. But, it could be modified for other voltage as well. It uses an inexpensive photo-transistor as the light detector. An n-channel FET is used to switch power to the lights. A transistor schema is included to provide some hysteresis.

This keeps the schema from fluttering the light during the transition from day to night and night to day. It is recommended that a plastic tube be placed over the transistor to prevent it from being illuminated by the lights it is controlling. By selecting the appropriate power FET, the schema could control over 100 watts worth of 12v lighting. (July 22, 2008)

Source: DiscoverCircuits

Thursday, August 21, 2014

How Put that Light Out! Wiring diagram Schematic

If you forget to switch off the light after leaving a seldom used room (such as the loft), there’s a strong likelihood that it could remain lit for months, running up an expensive power bill in the process. How can we prevent this waste?

It’s not hard for electronics enthusiasts to design a little schema to mitigate the effects of absentmindedness. The notion is simple; if the light is left on when the hatch or door is closed, a rhythmic sounder/buzzer signal produces an alarm that hopefully will not be masked by other noise.

Circuit Diagram:

The schema is powered as long as the lamp bulb is switched on by light switch S1. If the reed switch S2 then signals that the hatch has been closed, the sounder operates. The red LED, mounted outside the loft next to the entry hatch, also indicates that the lamp up there needs to be switched off. The schema does not use a transformer, meaning that the whole schema is at mains potential. For this reason the components must be placed inside an insulated plastic case for protection, with no way that people can touch any part of the schema (this includes the sounder).

The connecting wires to the LED and the reed switch contact must be fully protected to the same touch-proof degree too. For the sounder you can use any type that operates on direct current in the region between 1 V and 3 V. In this schema the operating voltage is limited by the LED connected in parallel to the buzzer. Using a red LED will provide around 1.7 V to the sounder. The current requirement of this kind of miniature sounder is about 5 mA.

Author: Stefan Hoffmann - Copyright: Elektor

Friday, August 15, 2014

110V LED light circuit diagram

Most of you who use 110V asked me LED light diagram which can be operated with 110V.By using this schema you can light up 4 LEDs form110V.Use white colour LEDs

Note:
# If you are under 10 dont try this schema
# Be careful when you deal with 120V
# Build this schema on a PCB