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Showing posts with label Mains-Circuits. Show all posts
Showing posts with label Mains-Circuits. Show all posts

Sunday, June 17, 2007

Flashing Neon lamp for Soldering iron

ar_subject: delabs formmail
message: How can I make a flashing neon lamp - 240 volt AC

I have been trying for 3 hours ( R-C circuits) but no sucess. I want to include it in my soldering iron socket to show the power is on.

Mail from HJ of UK


These circuits may help, let me know if this works.

I am sure a reading of above will help make your own. do not forget, i like a feedback.

delabs


You can comment on this thread with your homepage-blog URL, HJ can also give more details, or Indicate his blog. I am using initials of users, you are free to give more details. - Anantha Narayan - delabs


Thursday, May 19, 2005

Mains Voltage Monitor

i need a circuit design to detect generator voltage and display with LED for certain value of voltage. for example red LED"s for voltage under 180 V, green LED for 180-220V and Yellow LED for voltage above 240 V.

i would like be glad if you would like to help me design it!

mail from KB


I have some designs that may do that easily. Have a look at them. We could modify them to suit your needs.

First the 230V has to be brought down to say 2.3V with a transformer or attenuator. Then we have to measure it with LED bar graphs, choose color of LED as required. If the measurement unit is a sealed plastic box then it can be transformer less.

Look at these first. Mains Stabilizer Circuit, In DMM Circuits see ....analog and 3-1/2 digital display for +/- 199.9mV. in LM3914 you can light up a bar graph or a single LED to show the Level.

in Water Level Sensorsee Fluid or Water Level Sensor using reed relays - circuit example

These links also help. elektor.de/miniproj/details/020282.htm

DPM based on ICL7107 see AC voltmeter digital, 7107, pdf After you looked at all the circuits, Tell me how i can help you.

delabs


i have seen almost all the source you show me. i got more explanation and also more confusion...!
well, actually all i need is not too complicated but maybe its tricky for me. i got the idea about using voltage comparator via voltage divider, not using transformer like you said. it is more reliable and easier, isn"t? but again i got little bit trouble to design it!

is it easy for you anantha? i hope you will give me best solution for it! if you dont have mind i will wait for your design as comparison, but not in hurry! Ok, thank you for your kind attention!

mail from KB


I will make a circuit for you as soon as possible. Do you need just 3 LEDs or more. do you have experience in using 230V supply safely as it can give shock. give me more details if possible.

delabs


Again thank you very much for your attention on my question. actually it will be better to have 9 LEDS for 3 kinds. i have some experiences in installing 220/230 V but not expert, dont worry about that i will try as safe as possible.

i would like to install picohydro for my garden with power about 300 watt using induction generator. it will be expensive and not comparable to use complete controller as well. so i wondering to have voltage indication to estimate voltage condition, or even you have experiences with picohydro or minimum requirement for it (controlling, safety) like overvoltage protection, etc. again i will be glad for it....!
i will wait for your answers.

mail from KB


Can you please explain in brief what is picohydro and how induction generator is used. I have attached a circuit, It is not tested, It might do the job. You must have basic knowledge in building, testing and troubleshooting circuits.

After a study of the circuit you can tell me more clearly your needs.

delabs

Ok, induction machine can also used as generator if you at least:
1. Drive motor faster than synchronous speed (slip = negatif)
2. There is reactive power from outside (capacitor/Grid)
I think you know it! in my case i used 3 phase induction motor with 1 phase output only (C2C connection),its more reliable and much better than 3 phase output for small power! its easy to build! any way, thank you for your design...!i will try to study it before i build.

mail from KB

The circuits you asked for with some explanation has been published here.

mains-voltage-monitor-using-lm3914.html
simple-mains-voltage-monitor.html

delabs




Wednesday, October 20, 2004

stabilizer circuit

i kinda found myself in a place where the voltage is so low (80v-110vAC) and i need to boost it up to 220v so what can i do? i have a burnt stabilizer (that is the electronics part) so i need the electronics circuit to replace the burnt one can Anybody help?

post by FP


here is a circuit i made for you, i am not sure it will work, i hope it will help you learn. part of these ideas are over 20 years old. Stabilizer Circuit............... Stabilizer circuits

One more circuit, this is a bit complicated and it is not tested, it may not work that easy, just refer it to make your own design, it is just a bit of theory and my experience, i may be wrong at a few places. Electric Circuits

delabs


Tuesday, October 19, 2004

Lamp Dimmer

I need a simple circuit to drive a 12v DC (4amp) light. But, it needs to dim to 25% over a specified amount of time. Basically it needs to hold at 25% (4v) for a few seconds then fade and increase to 100%(12v) , hold for a second then fade back to 25%. Here are the electrical specs: - Input 12vDC @ 5amps - Output from 4vDC to 12vDC (amp draw may be as little as 1 amp or as much as 4.5) - Only 1 potentiometer is used to vary the rate at which the voltage changes from 4-12 - It must increase and decrease voltage in a very smooth way, so that it fades the light to 100% and then back down to 25%

mail from JR



I have a circuit in my website that may serve your purpose, visit Power Supplies Section. see this circuit.................switching power regulator for electroplating There may be some documentation errors in my circuits. If you are used to building and troubleshooting circuits then it is ok.

delabs


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