The project “Digital AC/DC Voltage cum Continuity tester” can be used to test 25 Volts to 500 volts AC/DC voltage continuity and open-circuit condition by displaying on the 7-segment display. There is the various advantage of “Digital AC/DC Voltage cum Continuity tester” over multimeter are Small Size, low cost, easy operation and requires no troublesome selector switch to select testing mode. To make a selector switch free circuit, we had used 82K impedance for DC and 220K impedance for AC. The testing procedure is very simple all you have to…
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Phase Sequence Change Indicator
The project phase sequence change indicator using 555 IC is used to indicate whether there is a change in phase sequence occurring or not by a beeper or a LED. We all know that in three-phase motor phase sequence is important because the change in phase sequence may cause trouble in machines. Circuit Description of Phase Sequence Change Indicator The circuit of phase sequence change indicator is divided into two main sections i.e. controlling section and the beeper section. The circuit of the phase sequence change indicator is shown in…
Read MoreSimple Battery Changeover Relay
It is economical to use a battery eliminator but with frequent power failure in most developing countries, it becomes annoying to change over from battery eliminator to battery operation every time the electric supply fails. Thus, we had designed a simple battery changeover relay. A simple way to avoid the nuisance is by connecting the battery and power pack in parallel. But the advantage with such a system is that when the eliminator voltage falls, even slightly (say from 6V to 5V), though the performance of the set remains unaffected,…
Read MoreRotation Sensor using 555 IC
In this section, we discuss another application of the most popular IC, the 555 timers. Introduced in 1972 by the Signetics Corporation as a bipolar integrated circuit, the 555 is also available in CMOS technology and from several manufacturers. There are various projects we had already posted in the timer IC 555-based projects section. Now, we have come up with another interesting project called rotation sensor using the most popular IC of all time 555 Timer IC. When more conveyors or equipment are used in the processing system and anyone…
Read MoreSingle Phasing Preventer Circuit
If we have been familiar with machinery, we all know how important it is to follow safety measures to mitigate injuries and accidents. A single phasing preventer circuit is one of the solutions we can look forward to. The phrase ‘preventer circuit’ itself portrays it. The single-phase preventer circuit is also a high low and unbalanced-supply voltage cut-off relay. To ensure complete safety for 3-phase machinery, the preventer circuit has been known to be handy. Generally, an induction motor burns out due to excessive voltage during an off-hour, a very…
Read MoreAC Motor Speed Controller Circuit Using AT89C51
Here is a simple circuit “AC Motor Speed Controller Circuit Using Microcontroller” which is used to control the speed of AC motor using microcontroller At89c51. The circuit uses the principle of changing the firing angle of TRIAC to control the speed of the motor. Here, in this project, we had to use various switches to control the speed whereas an LED bar graph is used to indicate the speed of the motor. Circuit Description of AC Motor Speed Controller Circuit Using AT89C51 The circuit diagram of the signal phase AC…
Read MoreOp-Amp 741 Based Sound Operated Light
Op-Amp 741 Based Sound Operated Light Circuit Diagram, Circuit Description with Working Principle and Parts List Introduction to Op-Amp 741 Based Sound Operated Light In contrast to where so far the technological development has brought us, this project might seem so plain, but it is a basic project that supports advanced projects, helps newcomers in the electronics field to understand the fundamentals, and being much economical provides extra credits to the users. This mini-project op-amp 741 Based Sound Operate Light builds up a small gadget/device which can be employed to turn…
Read MoreLoad Protector Circuit and Remote Switching
Introduction | Load Protector Circuit and Remote Switching Have you ever noticed the number of devices used at your house to serve your purpose? There are many. These devices require a specified rate of power to operate. Maximum variations in voltage/ power and load can destroy most of the devices like inverters and UPS systems since it can cause excessive heating of the output transformer windings and the active driving device and thereby damage them. And, some domestic appliances also need to be protected against under/over-voltage. This particular circuit serves the…
Read MoreDIY Resetting Protector Circuit for Computer
Introduction to DIY Resetting Protector Circuit for Computer With the speed of development in technology, it is no wonder that a number of software have been developed to prevent computers from quick execution of rushed commands which are mostly accidental issues. However, even the most advanced computer programs do not offer protection against the accidental operation of the panel-mounted reset switch. This often leads to incomplete installation of software, improperly closed files, and results in useless memory accumulation in the hard disc. Therefore we need a device which can prevent…
Read MoreDynamic Temperature Indicator and Controller Using Ardunio
Here is a standalone Dynamic Temperature Indicator and Controller Using Ardunio that also controls the electric appliance according to temperature. The use of Arduino technology makes this closed-loop feedback control system efficient and reliable. Arduino allows dynamic and faster control. Here we used a rotary encoder and liquid crystal display for more users friendly. The sensed and set temperature values are simultaneously displayed on the LCD panel in centigrade which can be changed Kelvin in scale. Circuit Description of Dynamic Temperature Indicator and Controller Using Arduino The circuit is programmed…
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