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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Can two devices be in series on an AC line?
I know that normally devices are wired in parallel on AC mains, lights, power sockets. Even in multi-adapter power sockets, things are generally in parallel.
Is there any reason the following layout ...
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How to change sync pulse into pulse signal
From this application note :
https://www.renesas.com/br/en/document/apn/cm-318-dc-power-line-communication
I want to change sync pulse into pulse to process in microcontroller
I am thinking to use ...
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How can I convert a variable 120VAC-600VAC to 120VAC without using a large transformer?
I have been asked to design a circuit that is able to convert from several possible input voltages (120VAC, 208-240VAC, 400VAC, 600VAC) to a single output voltage (120VAC.)
The output needs to be able ...
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Problem with MOC3043 for controlling TRIAC
I am having a problem with the MOC3043. I have designed a circuit to control a TRIAC for a heater as shown in the figure:
I used a 1 kΩ resistor on the control side/DC side of the MOC3043. Whenever I ...
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Measure unbalanced tri-phased power with 2-channel scope
Our robot is supplied trough our own "supply block", which is converting 3 phase AC (without neutral) into DC current and powering a 2 smaller devices directly between 2 pairs of phases.
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Mains voltage higher with load than without
I have a power socket wattmeter which measures 238 Vac (I'm in Europe, nominal voltage is 230 Vac). When I connect a relay before the wattmeter, it measures a higher voltage: 261 Vac. What's causing ...
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Is the RMS value the same after you pass it through a full wave bridge rectifer?
Is the RMS value the same after you pass it through a full wave bridge rectifier?
That is if the value was 230VAC (RMS) before the rectifier will it still be so after the rectifier? (ignoring any loss ...
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Using TRIAC on both live and neutral sides?
I am trying to design my electric vehicle charging station. There are some examples on net but they are designed by using relays at live and neutral outputs.
The main purpose of this design is to cut ...
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What will happen to electronics devices if the AC mains power misses one full cycle of mains voltage?
What will happen to electronics devices if the AC mains power misses onr full cycle of mains voltage?
In a 50Hz mains country, you have 49 sine waves (cycles) and 1 period of zero/no voltage. What ...
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What would be the voltage difference between two phases shorted together and the third phase?
I understand that it would be catastrophic for the two phases shorted together.
Say the line to neutral voltage is 2 volts and line to line voltage is √3×2 volts.
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Switch neutral on 115VAC, 220VAC 1 and 3 phase mains power
I have an application that will switch primarily motor loads. It needs to cover US style 115V and both single and three phase 220 and 440 (really up to 460) Not all cases have a neutral.
I'm in a ...
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Pros and cons of feeding domestic socket blocks with 3-phase cable
Our standard for domestic sockets is to run a 3x2.5 \$mm^2\$ cable (a single cable consisting of 3 wires each having a 2.5 \$mm^2\$ cross section) to the room and then join all sockets in one group (...
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Plugging in American standard 240 V into a European standard 240 V machine [closed]
I made the mistake today of not checking if the voltages were correct from an isolation transformer that converters American single phase 240 V (phase, phase, ground) to European 240 V (phase, neutral,...
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3 Phases measurement using a RP2040 mcu to check if all phases are available
I did build a single Phase voltage measurement controller and works.
The basic measurement methode is as this.
The Diode 1N4007 is used to eliminate the negative half cycles. Using a voltage divider ...
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240Vac circuit breaker on 110Vac circuit [closed]
I'm wiring up a 110Vac circuit, and for various reasons I'd like to use a specific breaker. This breaker is rated for 240Vac circuits. Is it ok to use it for 110Vac circuits? It mentions that the 2 ...
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Using a DC rated relay to switch AC
I'm trying to switch medium power 110V AC loads (10-20A) and I'd like to use an automotive rated relay. Naturally most of these are rated for DC loads.
Would it be ok to use a relay like this to ...
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Can I use a 3 A fuse to a 13 A wire?
I made an extension cable from a 3 A cable because I wanted a thinner cable.
The plug came with a 5 A, 240 V fuse but I replaced the fuse with a 3 A, 240 V fuse.
If the appliances I use take more than ...
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What is this device on an electrical pole?
I see this setup all over my neighborhood and am curious about one of the components. The houses on the outer edge of the neighborhood seem to get their electricity by tapping into one of the phases ...
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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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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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