Questions tagged [mains]
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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How can I power a PC-fan with mains power? [closed]
I am making a project where I want to integrate an old fan I have laying around. I want to plug it into a socket and start.
In my first try connected the red and black from the converter with the ...
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When does UL allow a user to access the a metal component connected to AC MAINS through a Y capacitor?
This is a 1kV SMPS design and it is considered a PRIMARY CIRCUIT by UL because it connects directly to 120V AC MAINS. It does not expose its 1kV output directly to the user, but uses the voltage ...
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What's the name of this connector, used to connect a mains power cable to the PCB of a RadioShack 42-3067 xenon strobe?
The power cord for a RadioShack 42-3067 xenon strobe got damaged very close to the appliance, so I need to replace it. I assume the connector on the end used to attach it to the PCB isn't reusable, so ...
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How to design a phase selecting switch without using a relay?
My project is an automatic phase switching device which will detect the phase unbalance between the phases and switch the load to the healthiest phase. The block diagram is below:
The project focuses ...
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Most efficient and cheapest way to drive a high power and consumption giant dimming LED matrix
I'm building a giant LED matrix for an art project.
Each "pixel" is a 12V RGB LED strip consuming ~23W, and has to be fully dimming controllable.
We're talking about 768 pixels with a total ...
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Power monitoring home electricity supply - No power generation yet power reverses direction at set times
Setup:
My friends house.
The house has Economy 7 (UK tariff) which has a single incoming supply but the meter then seperates it into "Day" and "Night" conductors.
They have been ...
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How do I calculate the required inductance and rating of a common mode choke used as an AC line filter?
I want to replace a common mode choke (240 VAC line filter) for a vintage computer power supply (Amiga 1200 PSU). The current choke is 47 mH, 2 Ω.
It seems that this footprint is quite hard to find (4 ...
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Why are conductive chassis double insulated appliances allowed in the UK?
MacBooks are infamous for 'buzzing' to the touch while charging. If another (properly Earthed) laptop touches one, it can flicker the screen or shut down. If I plug one of these same properly Earthed ...
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What are these jumpers between phases and earth in a residential distribution grid?
In my city, in quite a few locations there appear to be wire jumpers from each phase to the earth(?) wire. They appear to have ceramic insulators, so I suspect they aren't just directly connecting ...
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TRIAC dimmer switch not dimming
I recently attempted to reverse-engineer a TRIAC dimmer switch that I found in a lamp. The circuit was very simple, and I'll provide a schematic below.
From what I could tell by reading the part ...
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Mains: If I measure 30 VAC on a switched-off circuit, is it more likely that one wire is floating or "partly energized"?
It's a 3-way switch circuit powering an LED light bulb. I don't know how possible it is for a wire to be partly-hot at some level between 0 and 110 V. I know that floating voltages show up as ...
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Is it possible to add an indicator LED to a mains outlet?
I am building a power filter/distributor for one of my HiFi systems. Nothing fancy, but I wanted to add an LED indicator for each outlet, signaling that a device is connected and is drawing current ...
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Mains AC detection circuit - will it work?
I´m trying to detect mains voltage (230 VAC) across AC_SENS_L and AC_SENS_N.
AC_SENS_IN goes to an Arduino input with pull-up.
I only need to detect if voltage is present, not what voltage.
Any ...
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A switch that can only latch if power is present?
In a previous post, @Transistor showed hos to create a simple pulse trigger with a relay and a switch: Is there such a thing as a non-latching pulse switch?
Now I'd like to take the problem one step ...
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Earth pin in a 3-pin mains plug [closed]
I bought a new pressure washer online and it has a 3-pin plug as shown in the picture, but there are only two pins protruding out from it.
The two pins fit into my standard 3-pin socket and it works ...
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Utility meters in an AMF panel
Without the DG, the mains goes to, say, 5 flats in my apartment through 5 utility meters.
However, with AMF, the DG is shorted to mains. Wouldn't the utility meters count DG energy too?
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Why are batteries used with garage and gate motors in South Africa?
In South Africa (230V, 50Hz) as far as I know, most gate and garage motors are connected to a motor controller and powered by usually 12V lead acid batteries, which are then connected to a charge ...
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Preventing mains spikes from cheap water pump
I bought a pack of add-ons for my DIY CNC that has a water cooled spindle.
One of the items was the water pump. But when I switch on the pump, a fairly substantial crack can be heard in any speakers ...
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Reset mainboard from Raspberry Pi
I have a desktop computer with an Asus mainboard TUF_GAMING_B550-PLUS and a Raspberry Pi 4.
I log in remotely to the computer, but unfortunately from time to time it has an operating system issue, ...
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Using 5-wire cable in single-phase electrical wiring
Most single-phase household wiring is done using 3-wire cable (L/N/PE). However, a typical room nowadays has at least two wiring groups - mains that's done with 2.5mm² and lights done with 1.5mm². ...
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Using the phase side of the line as ground for an isolated dc/dc converter
This evaluation board mention connecting the GND of the board to the phase side of the line in order to use a shunt to measure current from the high side. In this example they use a capacitive power ...
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High-side energy monitoring with shunt
I'm working on an device that will switch a load and measure the energy of said load. This is for a 120/240VAC system. I plan on using the MCP39F511A for this job.
However in their datasheet and ...
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Digital signal to Power Line Communication (PLC)
For a hobby project I created my own digital protocol. I use a 16 Volt data bus (16 Volt = 1, 0 Volt = 0). My protocol is A-synchronous, half duplex and uses a transmittion speed of 4800 bits per ...
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Mains power supply safety
Curently I'm working on a design (for my own domestic use only) which is to be supplied by 230 V/50 Hz mains.
The IEC cord will be connected too one of these:
Mains Filter with Fuse
After that, the ...
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Surge protector + mains power adapter safe?
I was looking for a surge protected power strip/extension lead that could be mounted, have 6 or more outlets and came with a 5 meter mains cable with Type G (British plug) inlets and outlets. Having ...
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Building a space heater
I'm building a space heater, not for continuous use, but just as an experiment.
I made a nichrome wire coil that's 3.5 Ω and a fan that blows on it so hot air comes out of the other side of the tube. ...
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Why do power meters claim not to be usable for air conditioners? [closed]
As the title says, why do some power meters (especially the ones readily around where I live) claim that they cannot be used with air conditioners and a few more devices?
One typical such device can ...
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Neon bulb power source
I am designing a Nixie tube clock and need to power some INS-1 neon bulbs. The bulbs have a striking voltage of 65 - 90 V and an operating current of 0.5 mA.
To power the bulbs should I divide 170 V ...
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Discharging resistors on capacitor batteries
Yesterday I saw an industrial capacitor datasheet which stated that discharging the capacitors with resistors improves the life cycle of the capacitors, since it prevents electrical impulse discharges....
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690 VAC transient step causes ringing on secondary of step down transformer
I have an issue in a 50 Hz 690 VAC mains system, where external noise by some external thyristor equipment causes a quick dip on the main line voltage (blue line in image). And this dip causes a ...
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What is the potential of earth relative to mains live and neutral? [duplicate]
I'm confused about the theory of earthing in mains electrics. In particular, how the potential of "earth", the ground or literally the soil beneath my feet relates to the live and neutral ...
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Reasons for subharmonic mains noise in preamplifier
I have a preamplifier based on an OPA1611 that I wanted to characterize. The amplifier is in a fully enclosed and earthed metal chassis, which has an AC-DC converter in it. The mains cabling goes ...
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How to design AC/DC PSU PCB for safety
I want to convert 220V AC to a 12V DC output. I will then feed this 12V DC into a buck regulator to step it down to 5V DC.
Thus far I have done the 12V DC to 5V DC.
However, I am not sure what sort ...
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Can I interchange hot and neutral wires on a Shelly 1 AC input? [closed]
Shelly 1 can be powered by 110-240 VAC. I will use ti as a temperature sensor and I need to power my device from a regular European socket, which means that the user can plug into the wall in any ...
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What does 1ø mean in the spec: 1ø 220V 60Hz?
I'm hooking up my mini split (AC/heater) and it says the system needs 1ø 208-230V 60Hz.
What does 1ø mean in this context?
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Sensing a USB charger state via an Arduino powered via a separate USB charger
I want to sense the state of a 240 outlet. I have an adapter plug that I believe will allow me to use a standard USB charger (rated 120/240 V) to provide 5 V when the outlet is powered.
I also plan on ...
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Why can't I use a multi-adapter I bought in Hong Kong? [closed]
I bought a universal adapter named 'Grounded world travel adapter' in Hong Kong (attached the image). However, there was a sticker mentioning 'This product is not designed to engage with a main ...
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Low power isolated mains voltage zero crossing detection (without optocoupler)?
There are a lot of "classic" zero crossing detectors out there that drive an optocoupler more or less precisely around the mains voltage zero crossing.
I am not so much interested in ...
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Can I use an American power strip in a European outlet? [closed]
All my devices can take 110-240 V. I need to connect six of them and I only have a European outlet (any type) and an American power strip (with plug adapter).
Considering voltage will arc at 1 kV/mm, ...
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How to drive an induction hob coil from AC mains
I have been looking into designing an induction hob circuit, but haven't really found complete answers to my questions.
As I understand it, it's important to take advantage of the natural resonant ...
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How do plug-in photovoltaic cells work with three-phase current electricity meters?
First off: I'm German, and while I have a bit of knowledge of electrical distribution systems, I am not too experienced with English terminology for the technical terms. So please bear with me. Also: ...
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How do large electrical grids stay in phase?
I am a math student with some background in physics so apologies if the question is naive - but I'm trying to understand how large electrical grids like the Eastern Interconnection maintain locally a ...
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What are these spirals for?
A friend of mine made this photo on Mallorca of a overhead power line.
In my opinion the spirals are aviation obstruction markers. Any different information?
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Does peak mains power consumption of a laptop chargers depend on input or output parameters? [duplicate]
Disclaimer: I do understand that depending on the load the "power adapters" or chargers would pull a completely different values, so this question is about the theoretical "peak".
...
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230 V mains isolated polarity detection
I am trying to work out how to produce an isolated 5 V digital HIGH/LOW of the polarity of a 230 V mains supply.
Basically the aim is to be able to read an amp clamp at a set time interval in order to ...
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Digital output protection against accidental contact with 230V AC
I plan to build a "Wire Tracer" device to identify mystery wires around the house. I found this schematic, which uses a NE556 based tone generator and a contact-less receiver. Hopefully it ...
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With little electrical knowledge is it possible to get a standard US light socket to power a small 3 W LED? [closed]
I was attempting to make an LED light bulb from scratch using a UV 3 W diode and acrylic resin. I wanted it to be able to be used as a regular bulb. Is this possible?
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Design for 110 V brownout detector
I suspect that a power circuit in my home has an intermittent connection somewhere, and I'd like to test this to be sure (because if I'm wrong, then the equipment running on that circuit needs to be ...
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RCCB at inverter/power backup output
This question may be lame but I really need a solution. I am not an electrical engineer but asking this here to get help for my home RCCB setup.
I have an RCCB at the main output and it is working, ...
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Coaxial 75ohm cable parallel to electrical mains 127V AC @ 60Hz
Everywhere we look at, the same recommendation is made: "never run coaxial cable parallel to electrical cables". Well, I get it, but.... I have no other option™. More than that, those cables ...
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