Questions tagged [ac]

This tag refers to alternating current mains power. It usually applies to voltages with >100V RMS, but can also be used for ex. 24V industrial AC power.

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Help for voltage is being passed trough load, even triac is OFF condition

We are using below circuit for home automation. We are facing problem when 5v battery is not passing to the circuit,but even 1 volt is being passed trough load, even triac is OFF condition.. Please ...
222 views

Explanation of a sample circuit for the FL5160 Dimmer controller

While looking for dimmer circuits, I stumbled upon the FL5160 Dimmer controller and it's specification at https://www.onsemi.com/pub/Collateral/FL5150-D.pdf The example schematic (for example, the ...
99 views

Is a safe 110/120VAC benchtop power tap possible?

I have a benchtop power supply that provides +3.3, +5, and +/-12VDC. I've started cannibalizing small appliances for parts, and I'd like to have similar power taps for 110/120VAC. Does such a thing ...
121 views

Protecting malfunctions in relays which operate roller shutters (motor, inductive load)

I have a circuit used to control roller shutters in my home, which roughly can be seen in the schematic below. simulate this circuit – Schematic created using CircuitLab It works, but after ...
61 views

What determines the real world transformer ratio of a clamp on AC power meter?

The ideal step-up transformer, when the primary coil has 1 winding and the secondary coil has 60 windings would step up the voltage 60 times. With this improvised clamp on AC power meter, which is ...
443 views

Why do we use alternating current and not direct current for mains power plugs within a house? [duplicate]

I understand that for transporting electric energy it makes way more sense to have AC. But within my house, I don't think that argument holds any more. Devices I use (roughly ordered by power ...
26 views

Calculating Currents and Voltages in and AC RL Circuit provided below

I am studying RL Circuits with AC sources. I am trying to solve this circuit So far, I am only able to calculate the current iL through the inductor as for the other parts I can't grasp the concepts. ...
80 views

Railway overhead lines: What happens to other two phases in single phase railway power?

This is actually two questions. As my imagination I have the German/Swiss/Austrian/Norwegian/Swedish railway system on mind (15kV, 16.7Hz). I think conceptually the problem is the same on other AC ...
171 views

How to design an AND gate for 24V AC Thermostat Connection

I have a two stage furnace with a heat pump, and a thermostat that isn't capable of controlling the second stage of the furnace when in heat pump mode. However, I can configure it in such a way that ...
20 views

AC servo motor driver problem (new, more precise) [duplicate]

I was not precise in last question. My AC servo motor driver "panasonic MSDA023A1A" which I use on CNC cutting machine is started to display alarm code "Err_18", which stands for regenerative ...
113 views

Question about AC servo motor driver

Does anyone know what means when AC servo motor driver displays error code for "regenerative discharge", and stops working. What this mean in practical situation. This happens from 1 to 10 minuts ...
32 views

Can a MTS 101 2 pin ON-OFF switch rated for VAC be used in a DC circuit?

I'm currently looking at buying a bunch of MTS 101 rocker switches which are rated for: AC 125V 6A, AC 250V 3A For DC the rating is not available http://www.massuse-relay.com/details/MTSSeries.pdf ...
113 views

Why a CFL lights up when I touch it?

When there is a very low voltage (AC), even for a compact fluorescent lamp (CFL), it glows very dim (orangish in color) at the beginning of the glass but when I hold the glass just for a second, it ...
399 views

Permanent magnet synchronous motor (PMSM) equivalent circuit

I am trying to model a PMSM (permanent magnet synchronous motor) in LTspice and in order to do so I need to form an equivalent circuit. Through some research I believe the circuit should be formed in ...
174 views

Calculate torque from current induced in a single phase of a 3 phase AC Induction servo motor

I'm looking to measure the torque or slip angle on an AC induction (asynchronous) servo motor given the current induced in one of its phases. The servo and drive is yaskawa. Example data is shown ...
75 views

Input protection on a DC jack

I am designing an battery powered instrument with around 20-40Ah 3S li-ion batteries in it along with a 10A 3S(12.6v) external charger. Due to ease of availability and the current capacity I have ...
52 views

AC Circuit Analysis with Diodes and Op-Amp

The following circuit is given: The 2 diodes are idealised in the following way: All other parts have the following properties: I've been trying to figure out what the voltage at the entrance of ...
180 views

Voltage Equation in Time Domain

When we describe a AC signal (voltage is this case) in time domain we use an equation something like this below: $v(t) = V_m \mathrm{sin}(\omega 𝑡 + \phi)$, where 𝜔 is the angular frequency of ...
39 views

Ac signal of soldering iron tip

Did you noticed that when holding a LED with bare fingers and connect it to a soldering iron(ac type) it gets a little bright. I did it for other components to reduce their heat during the soldering. ...
215 views

How to wire 220v to 1 ch relay

I bought the following 1 ch relay - Link (433 MHz), which is just like the one in this video - Link. I want to connect it to my room lightbulb which uses 220v, the thing is I'm not sure how to wire ...
38 views

Power strips show fault in some outlets but not others

I'm not sure if this is on topic or not, but I thought I would ask. I have a few power strips (surge protectors) in my house that I use for computers, TV, etc. Some of these have a "fault" or "surge"...
141 views

I am measuring AC signal using an instrument amplifier AD623. This will be fed to an ADC in the 0/+5V range. Therefore the signal must be centred on 2.5V. A voltage divider will create the 2.5V using ...
44 views

Use of blender's PSU

I would like to use blender PSU board. To power motor of the blender. Whole blender consists of this this board, control board (which blew up) and motor itself. I am now trying to hack this board to ...
51 views

What's the use of the 4 outputs of a power entry module (Qualtek 864-10/009), and how to interpret it's circuit digram?

Main question: What is the purpose of having 4 outputs? If I only had pins 1 & 4, I would be able to use 115VAC when it's set to 115VAC, and 240 VAC when it's set to 240VAC. For 240VAC setting:...
159 views

Why does my lamp only work when plugged the “right” way?

I have found a halogen lamp that only works when plugged to the wall socket the right way. I am baffled by this behaviour. The lamp is similar to this model, and uses a bulb similar to this model. ...
98 views

What are the practical differences between AC and DC transmission?

I have a long (2m) but thick wire between transformer-based power supply and low frequency power amplifier. Know your best advice ahead, but no, I cant get rid of it. I can put it in two ...
1k views

Converting 220v 50Hz to 110v 60Hz

I have a situation which I'm not sure how to handle. I've purchased an appliance from US. This appliance is powered by electric motor (175W) and then I realized I cannot use simple step-down converter ...
47 views

There exists 110v/60Hz motors as well 220/50Hz ac motors rating, what determines the voltage of an electric motor?

I have seen the Toms question and answers for what determines the voltage of an electric motor? None of the answers not fulfilling. I was not able to comment to get clarify my doubt, so I’m posting ...
31 views

Fusing on dual voltage industrial device

Please forgive me if this question has been asked before. I am designing a heating device that will be sold to industrial consumers. In our past designs we have had multiple versions of the same ...
86 views

Crosstalk between AC and DC

First time asking a question but I've come across something I just can't find the answer to. Whether or not it's because a silly question I hope to find out. So I understand that with crosstalk ...
4k views

How to connect this 3 wire AC motor?

I have this NEW heat recovery unit from Amazon (shady quality, branded as made in UK but actually made in China) with this motor inside. It was supposed to have two speeds (Low/Hi). Question: How ...
214 views

Balanced delta source to Wye source by considering magnitude only is ok?

I read and derived formulas for balanced delta source to Wye source; it is given by Vy = Vd / sqrt(3)<30 but in some places I see people only dividing by sqrt(3) for conversions are keeping angle 0,...
55 views

run ac device on battery [closed]

I recently purchased a radio which unfortunately doesn't have battery option. Its spec is AC 230V - 50/60 Hz and 14 W Is there any way to use my Ni-Mh rechargeable cell battery with this device. ...
132 views

Transformer - I connected 50k resistance which burnt - why? AC

Wall supply gives as much power as a component uses. I'm trying to connect a 800W transformer to produce an arc of electricity. But I can't exceed 10A because home fuse will triger (so every device ...
184 views

Building AC to DC circuit that can not be run on a breadboard

First I have an AC power source. Can I solder the power source directly to a rectifier to make it DC? I plan on using a protoboard using the DC power but I need the board to be able to handle 2Amps ...
49 views

hump on rectified signal and inconsistency on gate signal

Following is the image of my circuit, I am working at the moment. This is not my own circuit but I am trying to understand and work on it. Following is the signal I am getting at Gate2. What could ...
176 views

Unity Gain Phase Splitter- Why outputs have different voltages

I’m trying to calculate the values of the biasing resistors for this phase splitter circuit. (I know the actual values of the resistors, but I just wanted to manually work it out). When I made the ...
59 views

1k views

Measured continuity between live and neutral

I was trying to get rid of the humming noise coming from my speakers in my hi-fi system. It is an old piece of equipment from back when the UK appliances did not come with the mains plug and you had ...
55 views

Can I use 220V inverter as 12V power supply?

I have a pure sine wave inverter, it charges a 12V battery and converts 12V from battery to 220V during a power cut. Since it can output 12V to charge the battery at quite a high current I was ...
129 views

AC/DC wattage conversion

I've got some common Dutch "huishoudsnoer" (household-cable? Mainly used for powering lamps. Not solid core, 2*0.75mm² cable) laying around, that's rated for 1380 watts. Our wall sockets provide 230V ...
83 views

What is the effect on kWh if the power company reduces line voltage to a residence? [closed]

We just received our power bill and it is showing a 30% rise in kWh for the past month. Nothing has changed in our home. We were even gone one full week in the month. To make it more interesting, ...
154 views

Pulse skip modulation vs Phase cutting for AC inductive loads?

What is preferred and safe mode for controlling power to an Inductive AC load when driven by a Triac? I am using a microcontroller with zero crossing optocoupler to drive the control signal and the ...
139 views

What enables the home appliances and electronics to work on single-phase?

Talking about the home appliances and electronics, if it is single phase that we are using in houses and currents get to zero every half cycle, how do the home appliances (using AC) and electronics (...
46 views

DC Variable power supply

I would like some advice on a particular circuit design for a variable DC power supply. Here is some information about what I want to do: I want to do open and short circuit tests on an alternator ...
66 views

To run 1.5 ton ac [closed]

i want to run a 1.5 ton ac through dynamo and generater(that run a dynamo) for that purpose how much KVA dynamo required and also a diesel generator(how many hp/KVA) will be required. NOTE:- generator ...