Cigarette Lighter Adapter- Cessna 172

On Fri, 04 Aug 2006 11:16:50 GMT, B A R R Y
wrote:
Many new cars include multiple outlets.

Yep and some of them don't even include the lighter portion, further
reinforcing that it is an accessory plug... Hell, Grace's new car has
a red insert where the ash tray normally would be that says, "NOT AN
ASHTRAY" on it... Since it's fabric covered, it would probably catch
fire if someone used it as such... I suspect it's for putting coins in
there and the fabric covering is so that it won't rattle as much...

On Fri, 4 Aug 2006 09:29:32 -0400, "Morgans"
wrote:
Do you have any idea how much power that would require, and the cost of the
inverter for a good sized, powerful laptop computer?

Looking at Grace's new laptop, I see a power supply rating of 100V at
1.6A, thus a 160W maximum draw... I have two inverters -- one for
whatever vehicle I'm currently driving and one for Grace's vehicle...
I believe that each is around 400W... On a trip a few years ago (back
before the popularity of portable DVD players), I had a small CRT type
TV, small home DVD player, and two laptops all running off a single
inverter...

It would be nice if there were 110V outlets in the cars, but I can see
how from a safety standpoint, the car manufacturers might be hesitant
from a liability standpoint... They would probably all have to be on a
GFI circuit at least... Easier for them to just put multiple 12VDC
outlets in the vehicles and let the user decide whether to run their
gadget off of it or to get an inverter...

With the inefficiency of most inverters, at least 1000 watt, and the price
goes into hundreds of dollars.

Most of the ones that I've seen have around 90% efficiency, sometimes
even more...

"Andrew Sarangan" wrote

I have an inverter that I bought for $19.99. It has a 150W contunuos
power rating. It runs my laptop just fine. Why do you need 1000W?

My son has a whopper computer he uses for video editing and stuff, and when
it cranks up, it really sucks the power.
--
Jim in NC

"Jim Logajan" wrote

If the expectation is that the inverter is terribly inefficient (say ~10%)
I could see it needing to draw 1000 W DC to produce 100 W AC. But I
believe
they are generally 80% efficient or better - otherwise they'd fry
themselves. Laptops aren't supposed to be very power hungry - even my
floor
standing "tower" computer (excluding my CRT monitor) typically draws under
100 W AC (I used a portable power meter to measure the power draw of my
computer equipment to size the UPS I needed for my home office).

The WallMart brand I think is Vextor, or something like that, and I have
found that it is not a whole lot more than 50% efficient.
--
Jim in NC

"Newps" wrote

What? I have a 150 watt inverter that works just fine for
recharging/running laptops, PDA's, cell phones, etc. It's an all in one
unit, no separate cord and device. About $20 at Walmart.

Look, all I can tell you is that my son's computer would not run on a 700
watt inverter, but would on a 1000 watt. That is not conjecture, that is
fact.
--
Jim in NC

Grumman-581 wrote:
On Fri, 4 Aug 2006 09:29:32 -0400, "Morgans"
wrote:
...

Most of the ones that I've seen have around 90% efficiency, sometimes
even more...
It has been many years since I was a circuit designer but I seem to
remember some theoretical limit on the efficiency of a static inverter
at 83%. This was caused by the energy lost in the transformer assuming
perfect switches (power transistors).

"B A R R Y" wrote in message
...
On Fri, 4 Aug 2006 12:52:03 -0400, "Morgans"
wrote:


My Toyota has both! G

How many watts, or amps?

I'm not exactly sure off the top of my head, but I seem to remember
400 watts. It's been fine for AC power tool battery chargers,
entertainment devices, my Icom handheld charger, reasonable
worklights, etc... Air conditioners, electric ovens, compressors,
and washing machines are out, but so what? G

Read the fine print before you continue to use it to recharge power tool
batteries. My inverter said do not use for chargers that hive a high
potentieal voltage, until the battery places a load on it, and it begins to
regulate. They may damage the charger.

Guess what. I didn't listen, and used a DeWalt charger; once, I got away
with. The second time, it quit working, and has not worked since.
--
Jim in NC

On Fri, 4 Aug 2006 15:55:03 -0400, "Morgans"
wrote:
My son has a whopper computer he uses for video editing and stuff, and when
it cranks up, it really sucks the power.

Laptop or desktop machine?

If a laptop, look at the wall-wart / power cord power supply to see
what it is rated at for input voltage and amps... Grace's new laptop
said 65W on it, but if you look at the power supply input
requirements, it says that it can need as much as 1.6A at 100V... Of
course, the power supply might be able to output more than the laptop
is actually needing since they probably want to leave room for
expansion by the user...

As a side note, for my LCD monitor on my desktop machine, it only
requires 40W according to its power supply...

In article ,
Grumman-581 wrote:

Looking at Grace's new laptop, I see a power supply rating of 100V at
1.6A, thus a 160W maximum draw...

Put a bigger, faster hard drive in it and the demand will go up.
She has growth built in.

On Fri, 04 Aug 2006 17:04:04 -0000, Jim Logajan
wrote:

"Andrew Sarangan" wrote:
Morgans wrote:
Do you have any idea how much power that would require, and the cost
of the inverter for a good sized, powerful laptop computer?

With the inefficiency of most inverters, at least 1000 watt, and the
price goes into hundreds of dollars.
--
Jim in NC

I have an inverter that I bought for $19.99. It has a 150W contunuos
power rating. It runs my laptop just fine. Why do you need 1000W?

If the expectation is that the inverter is terribly inefficient (say ~10%)
I could see it needing to draw 1000 W DC to produce 100 W AC. But I believe
they are generally 80% efficient or better - otherwise they'd fry
themselves. Laptops aren't supposed to be very power hungry - even my floor
standing "tower" computer (excluding my CRT monitor) typically draws under
100 W AC (I used a portable power meter to measure the power draw of my
computer equipment to size the UPS I needed for my home office).

The highest power laptop ac/dc converters today are rated at 120 W and
the roadmap is for 150 W. They'll probably stall there because of the
difficulty of cooling them even with efficiencies poking into the 90s.
I think silver box supplies for the top performing gamer boxes are at
around 500 W, but that may be low. Laptop power drains will drop when
laptops switch from cold-cathode fluorescent backlighting to LEDs. My
guess, based on what I saw at the Society for Information Display
conference in May, is that that is about 3 years away.

Don