# Tagged Questions

1answer
35 views

### Transforming 240 VAC to 5V/gnd

My 240 VAC relay can be either on or off. I'd like to transform that to 1/0 signal for an input pin on my Arduino. I may be able to build something with a rectifier, a step-down and a couple of ...
2answers
79 views

### Full-wave rectified sine wave representation?

Let us suppose I have an input voltage $V=V_0 \sin(\omega t)$ connected to a full-wave rectifier bridge which changes the voltage to $V=V_0|\sin(\omega t)|$. Now, if I want to work out the voltage ...
2answers
49 views

### Is it possible to run a Buck converter with rectified AC supply voltage?

I know that a standard Buck converter requires DC voltage as input. But if your primary input supply is a high AC voltage, it is not very easy to make a clear DC voltage out of it. For example, if I ...
1answer
191 views

### precise half-wave rectifier problem

I'm actually trying to build a precise full wave rectifier. But after a first failed try, I though I would better be off break down things to analyse every part of the circuit. So, I started building ...
5answers
966 views

### Why don't more devices incorporate full-wave rectifiers as reverse polarity protection?

Recently, I was introduced to the idea of using a full-wave rectifier, in order to protect against reverse polarity damage in DC devices. I hadn't even considered using a rectifier in an already DC ...
1answer
119 views

### AC rectifier and voltage regulator

I'm a mechanical engineer and my knowledge of electronics is letting me down please help. I'm looking to run a 1.5V led from an input signal that can vary from 0.3 to 0.5V ac. I want to make the ...
3answers
824 views

### Driving Permanent Magnet DC Motor via PWM

SUMMARY: I am currently trying to finish up a DIY project I've been working on for a while: Building an electric potters wheel. I acquired a treadmill and salvaged quite a few good parts from it, and ...
1answer
244 views

### Common DC ground with two bridge rectifiers

I have an old AC transformer with many taps off it at different voltages. Connecting a voltmeter to tap 2 and tap 3 gives 25V and connecting it to 3 and 4 gives 5V. I connected them to two bridge ...
1answer
215 views

### Can I use more diodes to reduce the voltage off a diode bridge?

I have a transformer labeled as providing 9Vac, 3.36 A. It appears to provide 9.4 v ac according to my multimeter. It runs through a diode bridge (WAB 040 diodes -- already fried the last version), ...
3answers
501 views

### How can I power and dim two sets of LED lights where one requires12VAC and one 12VDC

I am building a wall unit and I would like to use some LED Tape Light (12VDC, 48ft Total 1.45W/Foot) to light the shelves. Then I'd like to use a 12VAC adjustable LED spot light (5W) for the center ...
3answers
569 views

### AC heater, bridge and MOSFET, possible?

In my project I already have all the circuits for a PWM driving some high power MOSFET. Now the hardware guys are coming with this AC heater, and I've been breaking my head around Triacs and phase ...
1answer
482 views

### Electric circuit AC plug to DC Design Help

I'm new to designing electric circuits... but I have a simple project that I really need help on. All I need is a AC plug source to be connected to a 100 WATT bulb and a 3V motor(motor should only ...
2answers
800 views

### What do we use to convert AC to DC current in houses

Do we use an active or passive rectifier to convert AC current to DC current, and why?
1answer
736 views

### Regulated DC supply - need help with calculations

I am in the process of making a regulated power supply to convert AC(220V, 60Hz) to DC(9V, 500ma). I have worked out all the calculations and would appreciate if someone could double check just to ...
3answers
4k views

### What happens if an AC voltage is applied to a battery?

Today I was checking the voltage between charging terminals going to the battery of emergency lantern using a multimeter. The multimeter showed a DC voltage of 9V and an AC voltage of 4V. Could ...