# Low voltage Definition and 56 Threads

In electrical engineering, low voltage is a relative term, the definition varying by context. Different definitions are used in electric power transmission and distribution, and electrical safety codes define "low voltage" circuits that are exempt from the protection required at higher voltages. These definitions vary by country and specific codes or regulations.

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1. ### Using a low voltage supply in a class B amplifier

Hi, friends, I have two queries. I read somewhere that 1. In class B mode higher plate efficiency (tube amp) permits the use of smaller power supplies...and 2.For low level signals a low voltage supply is used, but as the signal level increases, so a high voltage supply is utilised. Q1. what...
2. ### What Are the Best Data Loggers for Monitoring 3-Phase Low Voltage Parameters?

Could someone please suggest types of data loggers that can be used to log 3 Phase parameters on the Low Voltage side of a transformer. Thanks
3. ### Electrical Low Voltage AC-AC or AC-DC Step Up

Ok, So my generator is producing ~1.5VAC. I need to step that up via transformer to no less than 5VAC max of 20VAC. Ideas or links to components I can use?
4. ### Determining Number of Turns for low voltage AC Generator

Ok, I did a quick search, and could not find answer. I need to determine how many turns / windings of 24awg magnet wire are required to generate no less than 5VAC no greater than 20VAC single phase using 3 of the N45 Neo Magnets rated at 13800 gauss each with 275-pound pull. Y'all give me a clue...
5. ### PDLC film on low voltage (3-6V)?

Hello community, I am working on a device project that requires a stripe of roughly 6cm*2cm to hide something beneath programmatically. A PDLC film could do the job, but I need to find a way to power with a series of coin cells battery, something between 3 and 6V. All the PDLC films I found are...
6. ### Low voltage across low resistance for heating elements

I am planning some low power heating devices in the 10 - 20 watt range and have been considering the usual high resistance alloys: nichrome, kanthal, and stainless steels (304, 316, 630). I have noticed that all of these materials are expensive. Is there some reason I could not just use steel...
7. ### Charging a low voltage battery with a higher one of same Ah

Let's say both battery have the same charge capacity of 3Ah Battery A has voltage of 3V and B has voltage of 6V. Battery A is completely discharged while B is completely charged. If I charge battery A with battery B, wouldn't B be completely drained because they hold the same amount of charge...
8. ### Method to create a high current and low voltage

How would I be able to produce a circuit that produces a very high current at a very low voltage? Would it be considered a reverse Tesla coil?
9. ### How to Configure a Power System for High Current and Low Voltage Demands?

I have to configure a power system for a furnace which demands very high current of the order of 50KAmps with low voltage of the order of 100 volts. Can anyone help me to get insight into how to configure the power system in boarder way. I am planning to use a transformer with thyristors .
10. ### Do Joule Thief's Work With Supercapacitors

I have a supercapcitor to power some of my small projects. The only problem is that the voltage drops gradually, unlike a lithium ion battery, in which the voltage is mostly stable throughout. My boost converter that I am using to boost the voltage up to 5 volts, stops working with an input...
11. ### Book for designing low voltage switches

Hi, Can anybody suggest a good book that discuss low voltage electrical switching hardware like circuit breakers, motor starters, automatic tranfser switches..etc? I can't seem to find any book that focuses on this.
12. ### Can a Zener Diode with a Breakdown Voltage of 1V be Fabricated?

Hello I must complete my research before Saturday... my problem is: how can we fabricate a zener diode with lower than 5.6v zener voltage? a curve in my reference book determine how much doping need to manufacture desirable zener voltage. but the minimum voltage we can achieve is about 2.5v in...
13. ### Can a low voltage situation cause a fuse to blow?

Hello all. First, let me say that have very little education in the electronics field, but I do know the basics. I recently got hired as a service tech for pressure washers and had encountered a unit that had a small engine (electric start 12v) with a blown fuse. A co-worker of mine has been...
14. ### Very low voltage AC Mains supply damage TV

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
15. ### Finding a Low-Cost Way to Step-Down Voltage for DIY Power Supply

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...
16. ### Low voltage switching of a pump, on a countdown

New member here. This might be the coolest subject for a forum I've seen in awhile (that probably sounds like robot spam). On to business... I have been scr*wed by a succession of people over our home's improperly plumbed hot water. It takes forever to get hot water to the faucets. I bought a...
17. ### Low voltage Low heat, battery powered heater

Hey guys! I have been following the forum for quite some time now. With all of you smart people out there, I am hoping you can help me design a heater, or at least lead me in the right direction. What I am attempting to create is a battery powered heater, to maintain a temperature of...
18. ### How can I design a high-output power inverter for low input voltage?

Hey guys, I need to make a power inverter that will take in .1-.3 volts, and the output needs to be as high as possible.
19. ### Dielectric test as per IEC for Low voltage panels

Hello guys, I was searching for what voltage does IEC standard call for Di electric test that should be done to low voltage panels? is it 2.5 KV for 1 minutes? If yes how how low voltage cable rated 600/1000 V can withstand 2.5KV without insulation failure?
20. ### Low voltage op amp to control high voltage series pass transistor

I am in the middle of designing a low drift and low ripple power supply for myself. To control the output voltage, which ranges from 0 to 20V, I am using an op amp whose output is fed into a Darlington pair of power bjts. The output of the Darlington pair is both fed back to the op amp's...
21. ### Does the Order of Voltage Transformation Affect AC Power Supply Output?

Hi all, I need to create an adjustable power supply (AC) that ranges from 0-6 volts with roughly 1 ampere at 1 volt. I have a variac transformer (0-130 volts), an isolation transformer and a stepdown transformer. My question is, does it matter what order I step the voltage down? In other words...
22. ### Why Does a Bulb Blink During Low Voltage?

why an bulb blinks during low voltage?
23. ### What does the Hysteresis do in a UVLO (under Low Voltage Lockout)

As fare as I have researched UVLO Under Low Voltage Lockout is a circuit which is used to turn off and on the output power of a electronic device according to voltage selected. For instance in a charging circuit the power will only flow to the load once the capacitor has charged to a certain...
24. ### Bonding High Voltage Source with Low Voltage Source(s)

I'm trying to get a better understanding on how grounding, bonding, and earthing works when high voltage sources interact with lower ones. For example, if you have a 400V AC, 20V AC, and 5V DC source all stored in the same aluminum cabinet (surrounded by a faraday's cage and connected to earth)...
25. ### Looking for a two leaf low voltage switch

Hello, I figure if anyone on the internet would know where to find a good solution to my issue, it would be you guys. For a tiny bit of background, I am building a Virtual Pinball Cabinet. I want to control two inputs with a single switch.. To be exact, I want to emulate the setup that...
26. ### Can a Battery-Powered Heater Wire Prevent Freezing in Fridge Drainage Tubes?

Hi there! I recently noticed that the little drainage tube in the back of my fridge keeps blocking up with ice. As a result massive condensation develops around the ice which eventually drips down the back causing the bottom of the fridge to fill with water the whole time. Apparently the...
27. ### Can't have high voltage function generator. What about low voltage Tesla coil?

According to many knowledgeable people on the internet, an affordable "high" voltage function generator does not exist. I would have liked to have had electrodes operating at >50v with frequencies up to 15 Mhz but it seems such a function generator is out of my reach. So I want to know if a...
28. ### Can I use ionized gas to make an electric arc at low voltage?

I am exploring what electricity can do and I have a question. First, can I use ionized gas to make an electric arc at low current? Second, If I can do this, what kind of ionized gas could I use (that is bottled), can I use?
29. ### Prove Electric Field Lines Go from High to Low Voltage Sources

Homework Statement In my electromagnetism lab, we had one electrode connected from the negative end of a power supply to one end of a conductive sheet, and the other electrode connected from the positive end of the supply to the other end of the conductive sheet. The potential difference of...
30. ### What Component Can Boost a Low Voltage Signal from a Computer Fan?

Hi all, I'm currently trying to build a sort of anemometer using an old computer fan. I have the hardware side of things set and was able to get my voltmeter on it whilst it was spinning, unfortunately it puts out somewhere between 1 and 8mV, which was a little less than I was hoping for as...
31. ### Inverter low voltage high current 5-12v in 13.8v out 30 amps

I am looking for a design to achieve the following. I have an off road camping trailer with a second deep cycle battery installed. The second battery never reaches full charge because of the voltage drop from the alternator in front to the battery in the rear of trailer To charge the second...
32. ### Differences between electric cables designed for High, medium and low voltage

I am trying to find the differences between electric cables designed for High voltage, medium voltage and low voltage electric transport, but I am failing to find an answer. I was wondering if you could help me with this. I know that aluminum is almost always the metal of choice, thicker is...
33. ### Low voltage relay and AC motor questions. Heeeelp. Please

Hi, I have a central vacuum system that has blown it's circuit board up. Basically a hoover with a low voltage switching system to fire the motors up. Finding a new board will be difficult so I'm going to rebuild the control system. I can solder, can rewire a house, but the finer points of...
34. ### Need to interrupt a low voltage lighting loop circuit

Need to interrupt a low voltage lighting "loop" circuit I configure a lot of low voltage lighting for a living. Although it's not a deal-breaker for the project I'm working on, I'm having a disagreement with a colleague as to whether the following configuration should work: Shapeable...
35. ### Electric Field lines running high to low voltage

Homework Statement Show from the given equation Vb -Va=-intergral a to b (E x ds) that the electric field lines run from higher voltages to lower voltages. Also show from this equation that the electric field lines are perpendicular to equipotential lines. The voltage in our experiment ran...
36. ### Need help building a device to manipulate low voltage

Hello, I need some assistance building a device. I want to input a voltage below 5v, process it and manipulate it by a programmed amount. It won't be perfectly even so I can't do it by a set resistance, meaning the scaling will be different. Example: input 3.74v process it as 73 degrees, then...
37. ### Discharging a high voltage capacitor using a low voltage source?

Suppose a capacitor is initially charged up to 2V, and then a 1V DC voltage source is used to discharge the capacitor to 1V, what is the energy consumption from the voltage source and what is the total energy loss? Assume the capacitor is connected to the voltage source using a resistor and...
38. ### Low Voltage AC Supply from Wall wart?

Hi - I'm just starting to build a few basic circuits and am looking to get easy access to a low voltage ac power supply. I pulled apart a power brick, and it only has 4 diodes, a cap, and a transformer. If I pull out the cap and the diodes and solder the cord to the leads on the transformer, I...
39. ### Low Voltage DC Power Supplies - Why?

Hi guys, first post here. I am an Electrical Engineering student (2nd year) and I have a part time job doing qualification and FMEA type work on power supplies. It's been a great learning experience and it's really helped me in my classes. Right now, I am doing a qual on a low voltage dc...
40. ### Building(or buying) a cheap relay that puts out at least 15hz at low voltage

i want to build a cheap relay that puts out at least 15hz at low voltage. the relay should operate with an input of 9v, and put out 9v but the output should be oscillating at at least 15hz(15 off-on, per second), and please don't tell me to build anything with circuitry or components. thank you.
41. ### Help measuring central Vacuum low voltage circuit

I need Help measuring central Vac low voltage circuit. I would like to put a relay in line if possible to trigger when the unit powers on. I measured 17.78 DC volts when off and then 0 when vacuum powers on. Seems like an odd voltage for the contacts that start the unit when you insert a hose.
42. ### Building an IR Modulator: Troubleshooting Low Voltage Output

Hey all. I am building an IR modulator but seem to have a small kink in the design. Here is my schematic: Here is a picture of the oscilloscope, connected between ground and the output of the TL555 timer and the output of the second transistor (the output pulse going into the LED's)...
43. ### Inductor Burning: Low Voltage Causes & Explanation

Is it true that when a lower voltage is applied across an inductor it burns up the coil? If so can someone please explain why?
44. ### Need cheap way/product to produce acurrent at very low voltage.

I need to produce at 0-5AAC in the millivolt range to test a current to current transducer. The ac amp source to the XDCR is from a 150:5 CT which is then converted to a 4-20mA signal. If my company had the money I would go with an Arbitor panel meter calibrater but that's not an option...
45. ### High Current Low Voltage Power Source

I am in need of a high current low voltage DC power supply, around 8 volts and around 250 Amps would be ideal. A transformer could take a 110v 20a house line and using Pincoming = IPVP = Poutgoing = ISVS and get (110vx20a)/8v= and get 275a which is good. But how do I make that DC...
46. ### Best software for low voltage single line diagram design and calculation

Best software for low voltage single line diagram design and calculation what is the best software out there for low voltage single line diagram design and calculation?
47. ### DC motor burns out at low voltage

I am trying to understand why a DC motor will burn out at low voltages. This idea comes from my dad who is a mechanic. He says that people that always start their car with a half-dead battery tend to burn out their starters and weld parts inside it together from the heat. Personally I think...
48. ### How Does Low Voltage Affect Induction Motor Performance?

I have got an 1HP induction motor rated at 230V(line), 60Hz. If I run it at 185V(line) at 65Hz, what factors are affected in its performance? I am hoping for your expert advices..
49. ### Low Voltage Problem: Do I Need to Rerun Wiring?

had a hanging light in diniing room. wanted to replace with a ceiling fan but junction box would not hold a ceiling fan. so went into attic pulled existing wire only about 6 inches up to remove from junction box. placed wiring in new junction box after it was secured. after installing ceiling...
50. ### Low Voltage BJT: Why 0.225V - 75mV?

i want to know why at some point the low output voltage for a bjt biased between 0 and 5 on the base and voltage 5 at the drain ranges between 0.225v and 75mv so which of them is the low voltage pz answer me now i have a project to deliver