Amateur questions - how to reduce DC amps ? Auto shut off?

[buddy]

1. Can someone explain, (in simple language, I basically know little
more than the names of various components) how to reduce DC amps?

I want to heat a container of water in an automotive use. I have one
of those cheap "heating coils" that you plug into the cigarette
lighter outlet, and drop the coil into a mug of water to make instant
coffee or tea. But two problems:

- I powered it from a battery charger and it drew 10 amps, way to much
- after only a few seconds, it gets way to hot to touch. I don't want
it hotter than, say, 100-120 F.

I think these two goals are compatible, but I don't know how to reduce
the amps.

2. I want the above to shut off automatically, both when power is
removed (i.e. car turned off) and after some amount of time, say 10
minutes - just like the rear window defroster. How to do this?

Thanks in advance for any ideas,
buddy

 

[MooseFET]

1.  Can someone explain, (in simple language, I basically know little
more than the names of various components) how to reduce DC amps?

This is really more of a "basics" question than a "design" question.
You also have a "design" question later.


First make sure you are reading this with the right font.
The "*"s should line up in the lines below.

*MMM*MMM*MMM*
*III*III*III*
*---*---*---*

Change the font until they do.

The term series means like this:

Wire More wire 3rd wire
------[Item1]------------[Item2]------

If you connect two identical resistive heater in series, the total
power and the current will be reduced in half. Each heater will end
up with 1/4th the power going to it.

I = V / R

I is current
V is voltage
R is resistance

Hooking stuff in series makes the resistances add.


P = I^2 * R

P is power

I want to heat a container of water in an automotive use.  I have one
of those cheap "heating coils" that you plug into the cigarette
lighter outlet, and drop the coil into a mug of water to make instant
coffee or tea.  But two problems:

- I powered it from a battery charger and it drew 10 amps, way to much
- after only a few seconds, it gets way to hot to touch.  I don't want
it hotter than, say, 100-120 F.

You can buy a thermostat that kicks off at 100F. If you wire this in
series with the heater (and it can take the current), you will have
something that turns on until the water heats above 100F and then off
until it cools below 100F. It will cycle on and off holding the
temperature in a narrow range.

If your thermostat can't take the current:
http://dkc1.digikey.com/US/EN/PDF/T082/Section.html
look around page 2063

Digikey may also have the thermostat you need.

I think these two goals are compatible, but I don't know how to reduce
the amps.

2.  I want the above to shut off automatically, both when power is
removed (i.e. car turned off) and after some amount of time, say 10
minutes - just like the rear window defroster.  How to do this?

If you can live with very inaccurate timing, you can use a second
small heater and a second thermostat and a relay. A push button will
start the timing.


Hefty push
button
!
-----
---O O-------
! !
! !
! Contacts !
! 0f relay !
! / !
+12V -+---/ O--------+---+-------- -------------> To heater
!
[Therm]
[ostat]
!
+------------
! !
) [Small ]
Coil of ) [heater]
relay ) !
! GND
GND

When the button is pressed, the relay contacts close because its coil
gets power.
As long as the coil continues to get power, the contacts will remain
closed and the heater will remain on. If the +12V input goes away,
the relay is de-energized. If the small heater heats the thermostat
hot enough, the coil gets de-energized.

The thermostat and small heater should be inside an insulated
housing. Screwing them both down onto a block of aluminum would be
how I would hold them in place. The more aluminum in the block, the
longer the delay.

This is extremely crude but these sorts of things are hard to break.

 

[buddy]

Thanks for all the replies. You're right, it might help if I explain
what I'm doing.

I am going to make and experiment with an HHO electrolyzer for my
car. I'm thinking ahead to winter time. I do not want to adapt the
heating coil I used as an example; I want to have a stainless steel
1/4" threaded rod as a heating element, about 1 foot long running
through the tank. I don't want the rod/heating element to get more
than about 120F because it will go through, with sealant, the acrylic
case.

I found this circuit which is supposed to turn on a heating element
(he uses a metal plate under his electrolyzer "jars") until the temp
reaches 72 , then turns off (he also incorporates turning on a fan at
115 but I am not doing that).

http://flapdoodledinghy.com/HHO_control.html

I don't understand how it is "set" to turn off at 72. (well I don't
really understand the schematic itself.)

I want to have a small in-car control unit which displays the
temperature of the electrolyte with LCD or LED readout. I found this
link

http://gaugeplans.com/

It says it can be fitted with an external probe. He will email a
schematic if I email asking, but the picture looks like it requires a
much bigger board than the readout itself. I want to keep the control
unit as small as possible. I also found this:


http://www.fishersci.com/wps/portal...=false&fromCat=yes&catCode=RE_SC&fromSearch=Y

It has a 10 foot probe wire which is long enough to reach into the
cabin, and the probe is stainless steel, also a requirement. But the
LCD is not lighted so it's hard to see (for that reason, I'd rather
have an LED display), it is battery powered but I want to use vehicle
power, and no "output" to use to set on/off for a heating element.

The way I want this to work in wintertime - or maybe I'm dreaming to
think I can do this - is like this:

Car off:
1. I know I'm going somewhere in about 20 minutes, so I go out and
push a momentary button to turn on the heating element. It heats (LED
shows it is on) until the electrolyte temp is about 70, or about 10
minutes auto-off (like the rear defroster), in case I change my mind
about going somewhere

2. I go out to the cold car in wintertime and drive away, the
electrolyzer power switch is on - it's always left in on position -
but it still doesn't go on until the temp reaches 60, then its LED
shows me it went on. The heating element goes on, an LED shows me its
on, it stays on until electrolyzer reaches about 70.

3. As noted, heating element must not get hotter than 100-120.

Is this doable?

Thanks,
Buddy

 

[Phil Allison]

"buddy " = TROLL

Thanks for all the replies. You're right, it might help if I explain
what I'm doing.

I am going to make and experiment with an HHO electrolyzer for my
car.

** Say no more.

This absolute, know nothing loon thinks perpetual motion is a reality.

Probably talks to space aliens and practices Scientology as well.

Ignore this ridiculous TROLL



...... Phil

 

[MooseFET]

Thanks for all the replies.  You're right, it might help if I explain
what I'm doing.

I am going to make and experiment with an HHO electrolyzer for my
car.

Cars are very bad experimental platforms. I suggest you get a lawn
mower engine and build some what to measure performance and the fuel
use. On a car, it is very hard to measure anything or even hold
things constant.

There really is no such thing as HHO it is a scam that that been
running around the internet for some time now.

Adding plain old H2O to the air going into an engine does improve the
performance. This is doubly true if you can adjust the compression
ratio and timing and detect the onset of pinging. You need to make
sure that the water is vapor or at least a very fine mist that does
not settle out on the metal parts. Water drops will break stuff.

Breaking the water into H2 and O and then feeding it into the engine
can give you some gain. The numbers on this aren't very good because
it takes more energy to break the water apart than you get back by
simply burning it. It can change the chemistry of what goes on in the
engine an make more of the other fuel you put in get completely
burned. If done exactly right, this will improve the efficiency
enough to make it almost worth the bother.

 I'm thinking ahead to winter time.  I do not want to adapt the
heating coil I used as an example;  I want to have a stainless steel
1/4" threaded rod as a heating element, about 1 foot long running
through the tank.  I don't want the rod/heating element to get more
than about 120F because it will go through, with sealant, the acrylic
case.

I found this circuit which is supposed to turn on a heating element
(he uses a metal plate under his electrolyzer "jars") until the temp
reaches 72 , then turns off (he also incorporates turning on a fan at
115 but I am not doing that).

http://flapdoodledinghy.com/HHO_control.html

I don't understand how it is "set" to turn off at 72.  (well I don't
really understand the schematic itself.)

Go with the simple thermostat that you can buy if you want to continue
down this path.

 

[buddy]

I have one on my car now, a simple design using 3" pvc tube, for 3
tankfuls of gas, about 750 miles. Increased mpg from 19 - up from
17.5 after switching to synthetic trans fluid and adjusting my driving
style - to 22 "city" (which is all I do) Very consistent driving
habits, routes, fill-up procedure. That's about a 15% gain. I spend
about $400/month on gas, so saves $60 /month. I have carefully
monitored several things and see no ill effects.

The one I am building now is a more efficient design and will fit
better, if it increases mpg great, if not I'm happy with the 15%.

Go with the simple thermostat that you can buy if you want to continue
down this path.

But as I said, it doesn't have any outputs to turn on/off a heater.

I will experiment with wiring heating rods in series as you described
in your earlier post. But I would still like to control it as I
described, rather than manually as I would have to do if I only had
the thermometer I linked to.

Thanks,
Buddy

 

[amdx]

Thanks for all the replies. You're right, it might help if I explain
what I'm doing.

I am going to make and experiment with an HHO electrolyzer for my
car.

Cars are very bad experimental platforms. I suggest you get a lawn
mower engine and build some what to measure performance and the >fuel use.
On a car, it is very hard to measure anything or even hold
things constant.

There really is no such thing as HHO it is a scam that that been
running around the internet for some time now.

Adding plain old H2O to the air going into an engine does improve the
performance. This is doubly true if you can adjust the compression
ratio and timing and detect the onset of pinging. You need to make
sure that the water is vapor or at least a very fine mist that does
not settle out on the metal parts. Water drops will break stuff.

Breaking the water into H2 and O and then feeding it into the engine
can give you some gain. The numbers on this aren't very good because
it takes more energy to break the water apart than you get back by
simply burning it. It can change the chemistry of what goes on in the
engine an make more of the other fuel you put in get completely
burned. If done exactly right, this will improve the efficiency
enough to make it almost worth the bother.

Let me add to your slightly negative evaluation ( I'm more negative).
The system starts with a battery that is LESS THAN 100% EFFICIENT( you don't
get out what you put in). Then you run current to a hydrogen (or hho)
generator, it is my understanding that these things produce heat among other
losses.
So the hydrogen generator is LESS THAN 100% EFFICIENT.
Now let's run the hydrogen into an internal combustion engine, oh, did I
mention that the engine is LESS THAN 100% EFFICIENT.
Ok, now this engine turns an alternator that is LESS THAN 100% EFFICIENT.
The alternator charges that battery that we already talked about. So I don't
see where the payoff of the system is coming from.
If anyone would like to add efficiency numbers to the LESS THAN 100%
EFFICIENT components (battery, H generator, engine and aternator.
I would be interested to see them.
We need leadership that will start us toward energy independence.
Nuclear, Better battery technology, oil from Algae, and maybe this Butanol.
What do you think about butanol?
http://www.butanol.com/page5.html
Mike

 

[Baron]

Adding plain old H2O to the air going into an engine does improve the
performance. This is doubly true if you can adjust the compression
ratio and timing and detect the onset of pinging. You need to make
sure that the water is vapor or at least a very fine mist that does
not settle out on the metal parts. Water drops will break stuff.

Breaking the water into H2 and O and then feeding it into the engine
can give you some gain. The numbers on this aren't very good because
it takes more energy to break the water apart than you get back by
simply burning it. It can change the chemistry of what goes on in the
engine an make more of the other fuel you put in get completely
burned. If done exactly right, this will improve the efficiency
enough to make it almost worth the bother.

I remember a device from a few years ago that injected water onto the
hot exhaust and fed the steam into the intake ! I have often wondered
whether it worked to improve fuel economy at all.

 

[[email protected]]

About once or
twice a year it's too hot to take-off from PHX.

That's more an air-over-the-wings density issue.


Mark L. Fergerson

 

[Baron]

Steam!?!? I know that jets taking-off from Phoenix often inject
misted water to cool inlet air and raise the density. About once or
twice a year it's too hot to take-off from PHX.

...Jim Thompson

I take it from that, its just more snake oil then ?
I didn't know about the water misting use by jet aircraft though !

 

[[email protected]]

I have one on my car now, a simple design using 3" pvc tube, for 3
tankfuls of gas, about 750 miles. Increased mpg from 19 - up from
17.5 after switching to synthetic trans fluid and adjusting my driving
style - to 22 "city" (which is all I do) Very consistent driving
habits, routes, fill-up procedure. That's about a 15% gain. I spend
about $400/month on gas, so saves $60 /month. I have carefully
monitored several things and see no ill effects.

The one I am building now is a more efficient design and will fit
better, if it increases mpg great, if not I'm happy with the 15%.

snip

simple physic will tell you that you that you can't get more out than
you put in, so the most efficient thing to do would be to throw it
away, less weight to drive around with

-Lasse

 

[MooseFET]

I have one on my car now, a simple design using 3" pvc tube, for 3
tankfuls of gas, about 750 miles.  Increased mpg from 19 - up from
17.5 after switching to synthetic trans fluid and adjusting my driving
style -  to 22 "city" (which is all I do) Very consistent driving
habits, routes, fill-up procedure.  That's about a 15% gain.  I spend
about $400/month on gas, so saves $60 /month.  I have carefully
monitored several things and see no ill effects.

I don't believe you. This doesn't mean that I think that you are a
liar. It is just that there are so many ways that you can be fooling
yourself and the ourselves are easier to fool than others.

You number of a 15% increase is extremely suspect because it is large
enough that we are getting into the area of the impossible. The
efficiency of an engine depends on things that you would have a very
hard time changing. The temperature that the burning fuel reaches and
the temperature it goes down to just before the exhaust valve opens
are two very important ones.

Since you know when you are doing the experiment, you are almost
certainly driving differently than normal. Did you know that wearing
a green hat reduces your fuel usage. Get a green hat and try it.
Keep very careful records of the weeks you wear it and the weeks you
don't. I can assure you that you will see a difference in the
numbers. Humans by their nature can't repeat things well or hold
things constant. It is part of what makes us better than machines in
so many ways. It is the one small downside to being a human
scientist[1].

[1] That is if you don't count never getting the girl at the end of
the movie.

The one I am building now is a more efficient design and will fit
better, if it increases mpg great, if not I'm happy with the 15%.


But as I said, it doesn't have any outputs to turn on/off a heater.

You don't need an output. You put the thermostat up against it.

 

[MooseFET]

 Let me add to your  slightly negative evaluation ( I'm more negative).
The system starts with a battery that is LESS THAN 100% EFFICIENT( you don't
get out what you put in). Then you run current to a  hydrogen (or hho)
generator, it is my understanding that these things produce heat among other
losses.
So the hydrogen generator is LESS THAN 100% EFFICIENT.
 Now let's run the hydrogen into an internal combustion engine, oh, didI
mention that the engine is LESS THAN 100% EFFICIENT.
Ok, now this engine turns an alternator that is LESS THAN 100% EFFICIENT.
The alternator charges that battery that we already talked about. So I don't
see where the payoff of the system is coming from.

You missed the important point about adding H2 and O2 to the engine.
This changes the chemistry of the burning of the hydrocarbon so that
it gets more completely burned. This means that it only works on
engines that don't burn all of the fuel, but such engines aren't hard
to find. Usually they are under the hoods of cars. You will find
that the losses from adding such a system are less than you expect
because of this.

 If anyone would like to add efficiency numbers to the LESS THAN 100%
EFFICIENT components (battery, H generator, engine and aternator.
I would be interested to see them.
 We need leadership that will start us toward energy independence.
 Nuclear, Better battery technology, oil from Algae, and maybe this Butanol.
What do you think about butanol?
   http://www.butanol.com/page5.html

I'm at the I'll believe it when I see it stage with that one.

 

[MooseFET]

I remember a device from a few years ago that injected water onto the
hot exhaust and fed the steam into the intake !  I have often wondered
whether it worked to improve fuel economy at all.

It reduces the amount of pinging. This lets you run a higher
compression and advance the timing. As a result you get better milage
but the effect is indirect.

 

[MooseFET]

  That's more an air-over-the-wings density issue.

No it is a lack of thrust. As the Saturn 5 proved, you don't need
wings if you have enough thrust.

 

[amdx]

So I don't see where the payoff of the system is coming from.

You missed the important point about adding H2 and O2 to the engine.
This changes the chemistry of the burning of the hydrocarbon so that
it gets more completely burned.

I didn't miss it, I'm just not ready to think a quart jar of water under my
hood is going to increase my gas mileage. I've had three people approach me
telling about there improved mileage or asking asking how to improve the
system (one of these on a diesel boat). But I'm willing to see some real
science on the idea, not just anecdotal evidence.
And as you said "I'm at the I'll believe it when I see it stage with that
one."
Thanks, Mike

 

[[email protected]]

Steam!?!? I know that jets taking-off from Phoenix often inject
misted water to cool inlet air and raise the density. About once or
twice a year it's too hot to take-off from PHX.

...Jim Thompson

I think I read somewhere that it wasn't really too hot to take-off, it
was just that noone ever bothered to make the temperature take-off
thrust charts go to
a high enough temperature, so a few times a year it goes off the
chart.

-Lasse

 

[[email protected]]

It reduces the amount of pinging. This lets you run a higher
compression and advance the timing. As a result you get better milage
but the effect is indirect.

and unless the engine is with forced induction, compressor/turbo, it
won't change much.


-Lasse

 

[neon]

you are wasting time and money if you read any motor magazine invariably you will read that this device will boost your power 20% and then again others gizmos. if you add all these claims guess what your car is now 150% efficient in reality probably considerably less. gas has certain amount of power as enjected there are no magical formula to increase that. if you do it will be not mentionable. you may got O THAT IS AN EXPLOSIVE SITUATION

 

[Charlie E.]

Steam!?!? I know that jets taking-off from Phoenix often inject
misted water to cool inlet air and raise the density. About once or
twice a year it's too hot to take-off from PHX.

...Jim Thompson

AIUI, the output from these systems, due to their inherent
inefficiency, is about 70-90% water vapor, and maybe 6-10% hydrogen
and oxygen. They look spectacular, because you have all this steam
pouring out, and it will burn because the ignition concentration for
hydrogen is so low, but most of the 'gain' from these things is the
water injection into the cylinders, not the miniscule hydrogen
addition...