Supply Definition and 506 Threads

Hi! I'm trying to build a variable voltage DC regulated power supply that is 0-30v and 2mA-3A. The problem I'm having is that as soon as I plug it into get a reading on my multimeter it reads 34v, even if I try turning the pot it does not change. I've rewired the pots and made sure the...

It is safe to add on extra socket by this way? Original connection: postimg.org/image/v6nshoygh/ Add-on connection: postimg.org/image/vkoccsyu5/ The extra socket is for light usage only. Water heater is instant water heater without tank. The switch is double pole single switch.

Homework Statement At $0.60 per bushel, the daily supply for wheat is 450 bushels and the daily demand is 645 bushels. When the price is raised to $0.90 per bushel, the daily supply increases to 750 bushels and the daily demand decreases to 495 bushels. Assume that the supply and demand...

Homework Statement [/B] Just a general question to see if I'm doing this right. The volume just doesn't seem right. Anyways we have a water supply of 1.6 million gallons with a pH of 9.93. We want to get the water to a pH of 6 using a 30% HCl solution.Homework Equations M1V1+M2V2=M3V3...

Ok folks, I haven't got much answers lately here and almost none with my last smps ground wire thing but here is another problem I'm facing , on the outputs (DC) from my smps after the bridge rectifier diodes and a smoothing filter cap bank I still get about 1V or bit more parasitics which I am...

Hello, I'm working on a project and I need some assistance. I need to adjust the negative supply voltage to an integrator opamp that I use for DC offset control based upon the resistance in a voltage divider elsewhere in the design. R12 is the trimmer resistor to adjust the CVS circuit and V5...

Hi Guys, I want a to buy a DC power supply to experiment with to power transistor amps that I want to build. I also I want to power up 12V car radios and other low voltage devices. I am looking at this one new from ebay which cost about $50.00. " 30V 5A Precision Variable Adjustable Digital DC...

hi guys, am working on variable speed drive system. My aim is to make a low cost drive system for three phase induction motor. Current system employs three phase AC-DC and DC-AC converters, which has 12 switches in total. I have one idea...i found three phase inverter topology which has 4...

I have an old motorcycle which I would like to fit with a modern CDI ignition. The ignition would be of the type typically fitted to dirt bikes and which require a high voltage AC source. They have a permanent magnet alternator with a separate high voltage stator for the ignition in addition...

I recently bought a DC power supply online to perform experiments that require electricity. I am not an expert with electricity so I have a few questions about it. It has a maximum of 10 amps and 30 volts, and both values are variable, however it does not show me the value of the current unless...

Hello everyone, I am designing the power system of a new circuit. It will receive an analog video signal and then be able to split that video signal to multiple outputs. I would like to have multiple ways to power the circuit depending on the application. One way to power the device will be by...

I am planning to run 230V single phase machine with 460V single phase supply. what will be the effects in RPM and torque? (( this is how i thought: as we increase voltage , current will decrease since power is same...decrease in current decreases the torque...to maintain same power, decrease in...

Hello community, I am building a device for which I will be using five Stepper motors (each 5v, 3a) and one brushed DC motor whose speed has to be varied and operates between 12V and 48V (350Watts). Also I have a heater which runs at 12V, 40Watts. My question is: How will I best power these...

Homework Statement a 12v dc supply is connected across 2 100k resistors in series.a voltmeter having sensitivity of 10,000 ohms per volt is switched to its 10v range and is connected to its 10v range and is connected to measure the voltage of 1 resistor. Homework Equations 1)sketch circuit...

How many led's 20ma at 3 volt can one run from a fixed supply voltage of 110 volt dc and a maximum supply of 20ma? I come up with 36.

Hi, When the modern 80 plus power supplies are quoted as being "87% efficient" on 100% load, does this mean that an 80 plus Gold PSU rated at for example 1000 Watts will provide 1000 Watts to the internal PC components, and therefore draw 1000/(0.87) = 1149.43 W from the wall? OR does it mean...

1. Homework Statement Homework EquationsThe Attempt at a Solution My answer to (b) was that power supply would have an internal resistance which is not negligible and will affect results. The correct answer is that shorted lamp A would cause damage to the lamps/supply. How is lamp A...

I just recently finished a new computer build for $280, or so I thought. I did it reluctantly. I was hoping to hold on to my old Core2Duo I built back in 2007 until 2022 when they stopped supporting Windows 8. In fact, I probably would have pushed it even until they stopped supporting Windows...

Hi everyone, I am trying to make a Summing Amlifier. I have simulated on computer where it is working correctly, but on real circuit it is showing some mal functioning. I am using OP 27 Op Apmp. The circuit diagram is attached. When I try to add DC voltage to AC sine wave, initially sine wave...

Q1. I know a DMM will anticipate a sineusoidal supply, thus there can be problems with spiky supplies. Even if you have a true RMS meter, it it's a spikey supply, non-sineusoidal, you still can't calculate the peak of a spiky supply? Does a DMM measure the peak, then calculate from THAT the...

Hello. I really don't get a concept of a way to generates negative voltage as a one of the supply voltage to typical OP-AMP. (Operational Amplifier) The output voltages is supposed to swing to more than 10 V thus supply voltages to OP-AMP should be +15V and -15V. I'm thinking of supply these...

Hello, I was looking for some sort of chip/IC that would accept a digital input of say 4-5 bits and that would adjust an output current. I am looking to have a +/-3.3mA current applied to a resistive load. It would also be helpfull (for testing purposes) if I could adjust the inputs so that I...

I'm sorry if this isn't the right place for a shopping question, but I'm not sure where else to go for advice. I got a https://www.amazon.com/dp/B0094KM4VK/?tag=pfamazon01-20 on sale and the unit is great, but the batteries don't hold a charge very well, especially when using rechargeables - it...

Hi, I have a question about LC series oscillators. Specifically when a DC supply is applied. Solving the differential equation for such circuit using as initial conditions at t=0 that Vc=0 and I=0 I get as a solution that the circuit oscillates and the voltage across the capacitor has an...

So in many books, authors state that the supply rate, u^3/l is proportional to the dissipation rate ɛ, in a turbulent flow i.e: u^3/l ~ ɛ where u and l are characteristic velocity and length scales of the large eddies. Many will also state that the small scale eddies have a time period or...

Hi I know little about this but I am wanting to wire up my 1mw green laser to my usb port to use it as a power supply it is 3 volts I'm wondering is there a program you can use to change the 5 volt output to 3 volts or would I need to use a resister in the wiring ?

I have a thing I want to build(scanning electron microscope) that requires like 5-10 different power supplies within the 1-20 kv range. Instead of building all of them, can't I build one 250kv power supply and split its power into all of these different high voltage components? How would you...

So, I get tired of seeing manufactures of various water nozzles claim that their nozzle magically increases pressure. Garden hose nozzles (this chunk of brass makes your 30 PSI into a pressure washer!¡!) and showerheads (Simpsons, anyone?) are particularly bad offenders. My question is would...

my 3inch plasma globe needs 5V 300mA dc supply... Can I use an adapter with 4.5V and 50mA output rating? If can't then what will happen if I still do use it?

Hello, I'm planning to light up a tile chess board with 64 LEDs (blue and white) set between the tile squares, and I was wondering if this Class 2 Battery charger output: 12VDC 900mA, would work to power 16 parallel sets of 4 LEDs + 1 ohm 1/8W resistor and a SPST toggle switch? The current...

Hello all. If I was to create a circuit with a 2 kV power supply, how would I reduce the current so that if I were to accidentally become part of the circuit, I would be in no danger? Another question: Does a bleeder resistor help? Thanks.

I'm looking to build a varied, high frequency power supply for a strobe light. Any suggestions on the best way to go about this? I would prefer to have it computer controlled so that I can change the frequency without manual input. Any pointers would be really appreciated! Thanks!

my electric supply company some time supply very low voltage which cause damage/burn out my Tv three time do you know any sort of device which disconnect power supply to my Tv and my Tv un harm from low voltage my electric company uses 220 volt supply or british system. please help me

I'm trying to re-purpose an old Compaq (and another HP) ATX computer power supply to use as a lab PS. I've seen tons of articles on line about how to do this, for example. I can't get it to even start up though. I have the power-on pin from the ATX connector that goes to the motherboard shorted...

I notice there are some functions in Mathematica in which you can't supply directly, an array of arguments but rather must give it a list. For example, GCD and LCM. I can use for example, GCD[2,3,8] and it returns 1. However if I code: GCD[{2,3,8}], the function call fails. I know of one way...

Hi. I have made a 12Vdc 3A unregulated power supply for my projects. I want to do some electrodeposition, and the 12V are a bit too high (It starts to electrolyze water and the deposited copper breaks very easily). I'm looking for a way to step-down the voltage without using too much money...

< Mentor Note -- thread moved to HH from the technical engineering forums, so no HH Template is shown >[/color] Hey. We are a group of 4 students, working with a project. The focus is directed towards the supply of hydraulic fluid. Four different piston cylinders subjected to different...

Hi again - partially stuck with a question and I'm not sure where to go. Hoping someone would be able to give me a hint :) A 75 W non-inductive light bulb is designed to run from an ac supply of 120 V rms to 50 Hz. If the only supply available is 240 V rms show that the bulb can be run at the...

Hi Im just wondering how mini projectors are powered up.. Is it a dc to ac ? Or just Ac? Also I am trying to look into a very small power supply but can't find anything as small as I want.. The smallest I've found is 13 x 5.6 x 9.7

Hi! I want to design DC power supply 12V 2A. Here is what I have done. Firstly, we need to transform AC main voltage. I will use transformer with ratio Np:Ns=16:1 : We must choose diodes with maximum forward current more than 2 amperes. I will choose UG8JTHE3/45.. This diode has maximum...

I've built a small voltage regulator that I can use with my breadboard or to test circuits. It is the first circuit that I've actually soldered together, so please disregard the hack job. The problem with the circuit is that when I hook up a very small load to the supply, the voltage plummets. A...

People say that the voltage across one resistor is equal to the voltage supplied. I've drawn a picture of a simple circuit with two points near the positive terminal. Apparently, if we take the potential difference of these two points, it will equal 9V according to the above saying (which can...

Homework Statement I performed a lab with a simple DC circuit. The circuit has 4 resistors (i.e. R1, R2, R3 and R4), which is the same as shown in the attached image. When the voltages across all resistors were added, they were higher than the source. How is this possible? The KVL rule states...

I am trying to drive a 115V DC brushed motor with a DC power supply. Most drivers I've found are for AC to DC and the 115V supply seems to be to much for most DC to DC. Has anybody worked with driving motors with large DC power supplies? Or does anybody now where I might find one? Thanks...

I have a power brick (transformer) that sends 12V, 17.9A to a device. I have another device that requires 12V, 10.83A. If I put a 1.7 ohm resistor in parallel to draw some of the current: \frac{12V}{17.90A-10.83A}=1.697312 Could I use it to power the 10.83A device? I'm just not sure if it is...

Homework Statement [/B] Parallel circuit consists of 100ohm resistor with 0.4A current, a 0.47uf capacitor with 0.177A current. Both connected across an AC supply, determineHomework Equations [/B] The supply voltage The supply frequency Current drawn from supply Power factor of the circuit The...

we talk about three phase supply .. I want to know that what actually is three phase..?? Its obvious there are three wires carrying current but what is "phase" ? Is there something like, transmission line is further divided into three wires ..?? Please explain..its quite basic.. and I am...

my friend gave a dc supply to a transformer in my college lab accidentally and the fuse went off can i get an explanation on why this happened?

I had an idea to put a rotating mill turbine into the pipes that supply water to home tap systems. So that as the water flows through, the turbine is spun and electricity is produced. But why isn't this actually done?

Hello, I'm 15 and very interested in physics. I'm building a safe nuclear fusion reactor as a science project. (I know how to safely handle high voltage and radiation) I have a question about the power supply. First off, I know that fusion takes around 40 Kilo-volts and it needs to have a...