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Mains electricity, typically a higher voltage AC waveform used to deliver electrical power to households. In North America 120V, 60Hz, in most European countries 230V, 50Hz. What most people will plug appliances into.

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I would just test this instead of asking here, but because this goes to mains, dangerous voltages and all that, I prefer to be safe than sorry. An old USB adapter stopped working, and I finally took ...
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Question: I'm facing a recurring issue with our control panels used for firefighting and fire alarm systems. During power failures, the varistors, responsible for overvoltage and undervoltage ...
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I'm building a lab bench power supply and I want to power it from mains voltage. My plan is to buy this transformer to go from 120VAC to 12VAC, then send the 12VAC through a rectifier, and then ...
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In the sample schematic Microchip Technology supplies in the data sheet for their MCP39F521 shown below, it appears that V1- is grounded. (V1- and V1+ are input pins for determining voltage.) Does ...
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A DIY project I'm working on uses electronics embedded in concrete, including 110V AC heating elements. As I was verifying my wiring before testing the device I was surprised to discover conductivity ...
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For years now there has been a random occurrence that happens with seemingly any power tap device I have with protection circuitry in it where it will make a audible buzzing/arcing sound for a few ...
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I recently saw this photo of the project "NATO-L", or North Atlantic Transmission One-Link. It's an under-sea powerline planned to connect Europe with North America. Does anyone know what ...
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I'm looking to design a circuit to measure AC mains voltage and current for protection purposes. I'm considering using the ADS131E0 ADC by Texas. The IC is made with power-line monitoring in mind. On ...
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Here's the most basic capacitative dropper circuit I could find with ten seconds on Google. Allegedly the voltage across the load will be about 5V. (I say "allegedly" because I couldn't ...
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Here are the two wiring diagram.
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I simulated the circuit shown below using MultiSim and obtained some interesting results. The simulation suggests that you can accurately reproduce the AC line voltage from the input to the output. ...
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The other day I was having a walk outside on a rural road and noticed something odd about the nearby power lines: What are these extra wires doing there? Context: Location - Europe, Latvia. This is a ...
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I have observed some unusual behaviour between my domestic 240VAC supply and an EV charger which has over-voltage protection. I'm posting this question here in search of a possible explanation or for ...
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I'm generating a square wave carrier signal of 125 kHz using 555 timer, I modulate it with a data signal generated from ATmega32 Tx pin (UART 9600 Baudrate) using OOK-Modulation, and now I'm trying to ...
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(Uber-edit - it has come to my attention that I am an ignoramus. This post is being left in place not to highlight my stupidity in particular, but to serve as a warning for others who think ...
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I have a property in a rural area that is serviced by a SWER line. This means we get one high voltage line from the utility into the service transformer, whose other leg is connected directly to ...
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I'm currently working on constructing a mobile power distribution unit and I need some assistance with a specific aspect of it. The unit is designed to accommodate both types of power networks found ...
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I was looking at adding a Y/C video input to an old TV, but it's got a hot chassis so it's not a trivial task. I thought I could just capacitively couple the chroma line, but then I looked at the &...
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I’m very interested in making some art that’d require me working in single frequency light — specifically the monochromatic light from the sodium vapour bulbs historically used in street lights. I can ...
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I'm pretty new to electronics. I'm building a device that has an aluminum enclosure, is powered by a 120V AC outlet, and requires roughly 520W of total power. My circuit is: AC input with a hot, ...
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I am designing an AC mains connector footprint in KiCAD which will be implemented using three 4.8 mm faston tabs for line hot, neutral and ground. Is there a norm or preferred order for the order of ...
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This video discusses residential power distribution systems, and the magnetic fields that surround them. At the 36 second mark of the video, the presenter states We have a distribution line issue ...
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I've just looked at a power supply for a client to try and diagnose some other issues, and I noted that the connections weren't what I expected. The supply is cascaded, one isolated UK mains to LV DC ...
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Beginner here. I am trying to make a "zero crossing" circuit with phase control. This is probably not the right name for the circuit. Basically, I have a sine wave (from the power outlet) at ...
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There is a house connected to German mains with hot, neutral and ground. Some distance away in the village there is a PWM source (most propably a solar inverter) which shows as 17kHz on the mains ...
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In the datasheet of this power supply, it is recommended to place the capacitor before the inductor for the mains voltage filtering circuitry, as it is shown on this image featured on the datasheet: ...
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I'm working on an ac mains control circuit and came across IsoMOV a new hybrid MOV/GDT for surge suppression. This appears to be a straightforward replacement for a standard TPMOV with additional ...
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I came across the following circuit on a random website: Source website My guess is this circuit is used by some extension boards as shown below: I understand that LED1 current (around 2 mA) is ...
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I want to implement an electrical mains level detector to interface with a microcontroller the simplest and most efficient way possible as this circuit would always be on. I’m trying to detect when a ...
fivejeez's user avatar
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I'd like to understand if charging multiple devices using the 240 V line's main power plugs forms a series or parallel circuit.
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Many AC-DC power supplies (say, 220VAC to 24VDC) have huge inrush current values. For example, a device might have an inrush current of 80A@230VAC. This raises the question of how to handle the ...
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Currently I working on very simple AC power mains distribution board. I want to use PCB-mounting AC line filter SCHAFFNER FN405-10-02 for EMI reasons. The datasheet provides simplified schematic: ...
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Just like the regulation graph (ouput voltage vs. input voltage) for a voltage regulator, is there a similar graph (power factor vs. input voltage) for a power factor corrector circuit? My aim is to ...
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You have a mains transformer with switchable inputs, 120V and 230V. In case somebody switches the input to 120V and applies 230V (which cannot be mechanically prevented, reasonably), the whole ...
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As soon as I plug in either my laptop or my speakers to the wall, I get an unbearable amount of noise in my guitar recording. Signal chain: Guitar --(1/4 jack)-> Audio Interface --(USB)-> PC --(...
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Using an incandescent light bulb in series with a mains-powered device is a well known trick to limit the current used by the device. It's great for testing devices you're unsure of. Unfortunately, ...
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I've been tasked with switching a number of 115 VAC, 60 Hz supplies to various pieces of equipment, and monitoring these output supplies on a PIC18. I'm confortable with the PIC and ADC side, but ...
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I have some misunderstandings with the grounding of a transformer. As far as I know, the utility transformer's (the last transformer before my mains plug) neutral point (star-connected point of 3 ...
electroeso's user avatar
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I'm not sure if its been done before but how feasible is the idea of building an computer expansion card (PCI/PCIe) that carries mains power on some areas of the expansion card being switched by ...
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UK mains voltage is 230V (RMS) with a tolerance of -6% and +10%. That gives it an upper limit of 253V (RMS). Lots of relays are rated up to 250V: e.g. the Omron G5Q series has a "rated ...
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In a Class I appliance, when a fault occurs that brings dangerous voltage in contact with accessible conductive parts, the installation wiring fuse or GFCI will not only shut down the dangerous ...
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At board power-on, the fan output connector has mains (230V AC) voltage without the fan connected, that drops to ~2V AC with the fan connected. At power-on, on the attached display, the board shows a ...
gdee's user avatar
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I am trying to control two 100W LED security lights via a motion sensor. The motion sensor is a Philips Hue and runs on the Zigbee network, the LED’s are 230V. I have purchased a Raspberry Pi and ...
en_passant's user avatar
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I'm building a small circuit to power an ESP32 with two different power supplies. Normally the circuit will be powered from AC, using a Mean Well IRM-02-5 AC-DC power supply to get 5VDC out of 220VAC. ...
Daniel P.'s user avatar
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I have a triac in a 60Hz 120V power line (as is often done for dimming) and want it to only switch on the power when the AC voltage is low (widely between -40V and +40V would even be fine). This is ...
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The premise of the question may be the problem so please let me explain first. In my home at night we have a bunch of nightlights and we run a small fan in each bedroom for the noise and/or cooling. ...
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I have noticed that my power supply (PSU) makes a VERY slight coil whine/static noise while it is plugged into the power outlet, regardless of the power status of the PC and the PSU. It sounds no ...
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I watched this video and wonder if its complete separation of primary and secondary coils is the normal way to wind a low-power isolation transformer (e.g., 60Hz 120V 120VA). I particularly want low ...
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Problem statement: Sailing boat with a 16A onboard breaker need to connect to a 32A onshore power supply. What is the minimum cable size from the onshore 32A breaker to the onboard 16A breaker. Under ...
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We have small non-isolated 230VAC devices that transform mains to LEDs running at 32V, 20mA. The lights are directly connected to live, neutral and earth like a standard lightbulb would be. Since ...
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