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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Controlling TRIAC with PWM from microcontroller
I am looking to control a mains heater with a microcontroller. It seems like most solutions use an optocoupler to signal the microcontroller at a zero crossing and another optocoupler to trigger the ...
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Identifying old Thermal Relay and its operating parameters
I was hoping that I could get help identifying an electrical component from a environmental chamber over 30 years old. It is a Sunvic Thermal Relay Type TDW-AJ 2301, 17A 200/250V AC as shown in the ...
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Should I connect a small DC motor directly to the mains without an isolation barrier? [closed]
I recently found out I'd need to pay upwards of $2k in order to supply my entire house with automated blinds. I feel like I can definitely do it myself for a fraction of the cost.
For this purpose I'm ...
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Location of Galvanic Isolator in marine installation
Almost every installation diagram I have come across for a galvanic isolator, has the GI installed in the shore power input line as follows:
I think can understand how this would make sense for a ...
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What is this U-shaped device that seems to be connected to one leg of an overhead power line?
Seen recently in Boulder, Colorado.
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Does the use of an IEC line connector on equipment require a UL cert?
My client wants to use a 12V SLA with a built-in line-powered charger in his gear. If I add an IEC AC mains line connector does this turkey now have to go through cert?
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Monitoring ground mA current via voltage transformer [closed]
The TL;DR
Can a voltage transformer act as a milliamp current sensor? They resemble in structure.
Explanation
I want to build an approximate ground leak milli-ammeter (0.1-30 mA) for some appliance.
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How can I power the SMPS with reduced input AC voltage while it's under full load?
I'm encountering a design issue with my switch-mode power supply that utilizes the InnoSwitch3-EP (INN3678C). The SMPS powers up and outputs the required V when the input voltage is 133VAC or higher,...
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Is this a viable amplifier circuit?
I am looking to measure my mains voltage input for a power monitoring circuit. This is the first time I have messed with an opamp to read out a transformer, as well as my first time simulating in ...
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How to safely avoid earth cable? [closed]
I'm a software developer (in the uk) and I've been sent some hardware to use as part of my testing, but the way the non-uk manufacturer is telling me to wire it up sounds very sketchy to me.
Its a ...
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Remove 50Hz noise from a system
I am working on measurement circuitry and one of the challenges I have is the 50Hz noise. Is there some analogue circuitry that could be implemented to eliminate this?
I am using multiple LDOs to ...
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Is an AC/DC converter with no visible fuse before the transformer inherently dangerous?
I've been using a generic, unregulated mains AC/DC converter (wall-wart) for a very low-power project. It's output was a bit prone to 50 Hz ripple, so I opened it up to investigate how the circuit ...
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Maximum Current in 3 phase ac charger for vehicles
I have seen a couple of AC EV Chargers that take in 3-phase inputs.
For US it is 120V. For UK and Europe it is 240V/220V.
My question is, I want to design the fuse and other MOV components and relays ...
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Power Supply Concept; Safety and Completeness - Feedback needed [closed]
I am currently designing a power supply for a circuit I have built.
I don’t have a great knowledge about PSUs, everything that I know I have learned in the internet. Unfortunately, my engineering ...
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Purpose of Isolation in Power Supplies
I have a general question.
Suppose, I have a PCB, (an electronic device), which is powered from the Electrical socket (from mains grid). Let us assume it is single phase.
When the mains power supply ...
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electrical safety for UK -> NL move
We are planning on moving back into the EU. We have a lifestyle of UK based appliances, and will need to update/refit/replace them all.
I see that EN / "Europäische Norm" is very well ...
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Design Review Request: AC Mains Monitoring
I am designing a PCB to monitor 240v RMS mains with a ZMPT101B and YHDC SCT-013-000 current clamps.
I am rectifying with an LS05-13B05R3. I aimed for 32mil clearances and widths with no overlap of ...
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How do you understand the kWh that the power company charges you for?
I really didn't know how to phrase this question. But here are the details.
First I understand the simple 10 x 100 W for 1 hour is 1 kWh.
But what I want to know is at what time interval does the ...
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Mains Plug Soldering Wires
So I have a few extension leads all are 13A rated but the cable length is too short just 1 metre. It would be cheaper for me to rewire them than buying new extension leads.
I bought a reel of the ...
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Measuring Differential mode HF on mains with oscilloscope
I want to measure Differential mode HF 9kHz to 100kHz with 3dB accuracy on my 230V 50Hz mains. Is the following concept good?
Let's imagine a first-oder high pass filter with its entry voltage U_e ...
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Single phase energy meter reports Phase current as 0A but neutral current 1A [closed]
When I switch off all my appliances, my single phase energy meter reports phase current(Ph) as 0A, but neutral current(nE) as 1A.
Also on the meter display it is flashing the earth symbol.
The KWh ...
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Reliable fail-safe optoisolator
I would like to add an extra fail-safe to a optocoupler. My current approach is to transmit a pulse of very specific frequency and pulsewidth on a clock on the high voltage side through the ...
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AC-DC Schematic - Is this a Death Capacitor [closed]
Is this a death cap? I think it's not a death cap because it doesn't connect to the DC ground, but I'm not 100% sure.
Image Source: Hi-Link HLK-20M24 Datasheet - https://www.rhydolabz.com/documents/...
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Detecting presence of mains voltage using Microcontroller, low power solution
I'm currently designing a 'smart' light switch, controllable from Microcontroller and physical switch. I am looking for a low power solution to convert signal so that the Microcontroller can detect if ...
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Shared neutral betwen 120v AC line and 82v ac output of triac phase dimmer?
I'm building a power supply for an old photographic enlarger (LPL/Saunders 4500ii aka 7451).
The enlarger has a jones connector with four pins for ground, a fan (120v ac), and a 200W bulb (82v ac RMS),...
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Highly accurate DIY friendly (cheap) power load
To avoid XY question, I start with my motivation and then my question.
I have an Emporia Vue2 (in-panel) power sensor but it is known not to be very accurate. For me there is a discrepancy between the ...
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Is USB-C unsafe in humid/water conditions? [closed]
We had a case in France of a teenager who died by electrocution while taking a bath when his phone that was being charged fell in the bathtub (as reported by the press).
How is it possible taken into ...
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What is the simplest / most elegant way to passively select power supply based on voltage levels?
I have a problem and my thinking seems to be a bit stuck.
I want to design a power supply that works on both mains voltage (120VAC to 240VAC) and voltages below 24V (AC or DC). There's only a single 2 ...
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Modular equipment to detect N and L swap in single-phase 230VAC feed?
Say I have a single-phase feed with N and L (no PE) that comes into a distribution board. I have equipment for detecting over/undervoltage, but what equipment can I use in order to detect someone ...
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Can you wire a breaker directly to an extension cable? [closed]
I have a modular UPS system, it provides power from mains or inverter depending on which is available. The power is provided to one short extension cable to which appliances are connected.
For safety, ...
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Is it possible to design a compact antenna for detecting the presence of 50 Hz mains voltage at very short range?
I have a mains cable buried in the wall. I would like to permanently place a small battery powered device on the wall over the cable's location and have the device be able to detect if the cable is ...
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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
I'm in Europe. Out standard for domestic sockets is to run a 3x2.5mm² cable (a single cable consisting of 3 wires each having a 2.5mm² 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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When using a class 2 built-in power supply, do I still have to attach metal parts of the device housing to PE?
I've got a project of a DIY microcomputer used for control and measurement purposes, which gets mains power via a Meanwell IRM-10 "AC/DC converter" mounted on one of the PCBs, which are then ...
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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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