Changing A System For 120 Volts AC to a DC system

LOUIEUP,

What kind of current are you dealing with ?

How many amps of DC do you need, and at what voltage?

What kind of equipment will the D.C. be used to energize?

Depending upon the answers to the above, a simple rectifier circuit may suffice - either half wave, or full wave, (again, dependent upon the efficiency that is expected from the circuit).

Rectifiers can be purchased, or constructed out of a series of diodes. A reservoir capacitor may be added, in order to smooth out the voltage.

I am trying to persevere the environment we are living in. The many 120 VOLT AC appliances that I own are some of the examples that people who use frequently and carelessly. They are the major cause of the ozone being deleted from the atmosphere. I am not too good at handling all the electricity terminology but this is a phrase that is on the label, 60HZ per cycle.

I have at least one appliance to turn into a battery operated unit, as it draws 75 watts of household current/electricity. Ths is one of my appliances that draws a mediocre supply of electricity. If I can convert this appliance to use less power, per operating cycle, then I will change more appliances and preservre this fragile environment. What is a rectifier, along with a diode?

I wantb this unit or appliance to maintain the same output that it does when it is plugged into a standard household outlet.

I am eagerly waiting for your response.

Sincerely, Louie

Dear questioner, what you want to do cannot be done.

Try working out how long a battery operated hairdryer needing 1000 watts of electrical energy (for today a below average level) will work for how long on a 120 amp/Hour car battery??? Simple Ohms law.....

And picking up a car battery......recharging it.....?

Why do you feel that 60hz is a problem?

What has 60hz to do with ozone?

Louieup wrote: I am trying to persevere the environment we are living in.

REPLY: Bravo! but so are many others. If you really believe the appliances you use are the major cause of ozone depletion, stop using the appliances! Your own statement: "If I can convert this appliance to use less power, per operating cycle, then I will change more appliances and preservre this fragile environment"

This clearly highlights the real problem. You are not prepared to do without. You simply want the same convenience but hopefully at a lower environmental cost to ease your conscience or whatever.

Muscle power as opposed to technical innovation may in fact be more beneficial to our health than better technial design. Walking and riding a bike is promoted as being more healthy than riding a car or even a motor cycle. Unfortunately, none of the above are suitable in some hostile environments many people live in. A one mile walk in summer could be a deadly activity if done in minus 30 below weather during a howling blizzard. Just one example. So what good does it do to live a mile from work if you still have to walk year round? Perhaps the solution to ozone depletion is to generate lots more ozone. Better do some more homework Louie, before you embark on some quixotic quest to save the world from itself.

Louie you will have to do better than that. What voltage, amperage, and loads. Are you asking to use existing wire and switches? And why would you want to do this?

Except for utility applications requiring stored power for backup, there really isn't a lot of demand for DC systems considering the additional problems they entail.

Lastly, what part of the world are you in? I design and build such systems but in Canada.

regards

Elnav

However it's done it is well worth changing the socket outlets and plugs on the DC system to be of a different pattern to those on an ac system. What is not wanted is to plug something into a DC system that is incompatible with it. Given that most appliances have some form of transformer at the front end of their ciruitry these days, all these are at risk if the plug change is not implemented.

On boats with a 12VDC or 24VDC electrical system, it is common to use BS546 5A round-pin connections on the DC, with BS1363 13A fused plugs remaining on the AC; the AC circuits are fed via a suitably-rated inverter.

http://en.wikipedia.org/wiki/Domestic_AC_power_plugs_and_sockets

It might be better and simpler to leave the fixed installation as AC and convert to DC wherever needed using a handful of bridge rectifiers mounted in boxes at the end of suitable leads that plug into the AC wall outlet. The fixed installation then remains untouched, and DC is provided at the point of use at the moment it's needed.

Here . . .

This ought to do the job.

i think electronic rectifiers wouldn't be appropriate for this job as thier avalanche point is very high and they can't tolerate this much voltage..

i think u must adopt power electronic components for this job like power rectifiers as they use thyristors which have very low avalanche point.

You gotta love all these answers. Have anyone even noticed the part that says "It needs to be done automatically, leaving the 120-Volt cord plugged into the wall outlet, while that is being accomplished". Sounds like he is yanking everyone's chain so to speak.

Sounds to me like what you want is an Uninterruptible Power Supply (UPS) where you automatically switch to using power from a backup source such as a battery when the main grid power goes down. There are many vendors out there who would be happy to help you specify and purchase an appropriately sized system for your needs.

The Guy has not got a clue about electrics or electronics, or he would have supplied proper details......he probably does not even really know enough about AC or DC to know if the question was even slightly valid or not!!!!

Typical CR4 "I want XXXXXXXXXXX!!" and no info!!!

You're right Andy. But consider this. Its obvious that many of the questions come from students who don't have a clue. And more than likely the schools don't offer adequate teaching, support or even have a decent engineering curriculum.

I was fortunate, in that I happened to be associated with a number of engineers ( parents of my fellow students) and found some willing industry managers with enough time to help me.

I was even more fortunate in attending an experimental high school program specifically aimed at future engineers. How many schools start teaching 13 year olds the rudiments of engineering these days, while also maintaining the scholastic curiculum for university bound students; Science, chemistry, mathematics?

At that age most kids haven't got a clue what sort of career they want, too many bewildering choices.

By age 15, I was encouraged by my teachers to write 5000 word technical papers on such things as ion doping for semi -conductors manufacture ( this back in 1965 ) or computerized traffic control systems (thanks to GE who provided me with the complete systems operation manual for Toronto's then new computer system) I was also rebuilding car engines and wiring up houses. (practical hands-on training)

Sadly such school programs no longer exist as far as I am aware.

What is perhaps worse, is the fact many schools do not teach students how to ask the relevant questions. In addition, some school authorities are lax in enforcing rules prohibiting blatant plagerism and outright theft of copyrighted material.

Homework done by proxy ( ie cribbing from the internet) does not encourage original thinking. In fact our society often condemns original thinkers as renegades and non conformists.

You are probably right, you had some good luck, most people have to make their own luck.

But by posing such badly worded and phrased questions (that I personally do not think that it is a students homework question!) in such a manner, and then cleaning their b*******s for them will not help them in later life!!!

You are just too kind.

I am not as I have spent many years teaching and I learnt a lot from my students, all of them professionals, you have to S T R E T C H them and push them to their limits and "EH VOILA", the limit has been pushed even further away....

Let us wait and see what happens....If I have scared them away, they are probably school kids as you said, but if they come back with full infos......

"Dear Whomever" do you want AC supply to DC supply changeover or UPS ? inverter to be utilised , or just rectification from ac to dc , LOUIEUP you rather look for a technecian in your area and let him do the survey for you , he can guide you and explain with clear terms and help you out , also your energy supplyer can advice you ,you have to be specific for application you are intended to , should be aware
of load (watts) , ampere ratings of applications ,proper grounding , safety precautions .

Converting a motor from AC to Dc is basically impossible, with the exception of universal motors, such as are found in some small drills and hand tools.All of that aside, even if you replace every motor in your home with a similar DC motor, the total power is going to be about the same, so it will not save the ozone or environment any more or less.If you want to save electricity,and therby reduce environmental damage,make sure your home A/C or heat pump has a high SEER.A heat pump is cheaper to operate in most areas, because it is cheaper to move heat than to make heat, and a heat pump moves heat.(Aux heat strips aside).A ground-source heat pump has the highest SEER available, and domestic hot water is free in the summer.

Your idea of converting a/c to dc will result in more energy usage because the conversion is not 100% efficient.

Put a brick in your toilet tank to reduce the volume of water used in every flush.Over a year's time it adds up.

Flourescent lighting is also an energy save, and super efficient LED Lighting will soon be availble for replacing incandescent bulbs.

There are many ways to save energy that are tried and true.Do some research on line, and you will find many more.