It's my understanding that a person should never use a modified sinewave
inverter with a laptop, that we should always use pure sinewave
inverters with laptops, as the modified sinewave units are harmful to
the life of the laptop's battery.

Question #1: Is this true?

Question #2: How do I tell the difference? I have 2 inverters I use on
my boat, each from a different manufacturer, and neither one says
anything about the sinewave characteristics.

In article ,
Floating Mind wrote:
It's my understanding that a person should never use a modified sinewave
inverter with a laptop, that we should always use pure sinewave
inverters with laptops, as the modified sinewave units are harmful to
the life of the laptop's battery.

Question #1: Is this true?

Short answer: no it is not true.

Longer answer:
Most, if not all, recent laptops use powerbricks that are of the
switching type. You can check easily: if it accepts 90-250V 50-60Hz,
it's a switching powersupply. Switching powersupplies don't care
what wave form it is fed, so any inverter will do fine.

Regards, ted

#1: Not True. I think it's worth knowing if you have pure or modified
sign wave for other reasons (microwave ovens for example need a lot
more power under one vs the other), but for laptops it does not matter.

#2: Check out the vendor's web site support area or call them. If they
say pure sinewave, and there not boasting about it on their website or
manuals as a feature of their inverter, I would be suspicious you got
the correct answer.

I power my laptop computer via my boats battery, saving a little bit of
energy, plus I avoid generating annoying noise. I also power my TV and
DVD thte same way, using DC to DC adapters ...

http://www.powerstream.com/Produz10.htm

The microwave still uses the inverter, but nothing else. The benefit
was eliminating any noise from the audio output of the TV (in
combination with using an RCA to RCA filter between DVD and TV, to deal
with a ground feedback issue), and eliminating noise from the cabin
(from the inverter, hum and/or fan)

Dan
Huntington, NY


Floating Mind wrote:
It's my understanding that a person should never use a modified sinewave
inverter with a laptop, that we should always use pure sinewave
inverters with laptops, as the modified sinewave units are harmful to
the life of the laptop's battery.

Question #1: Is this true?

Question #2: How do I tell the difference? I have 2 inverters I use on
my boat, each from a different manufacturer, and neither one says
anything about the sinewave characteristics.

My laptop is newer, less than 2 yrs old and I checked the power supply,
so all is good here.

Thanx for the information both of you.

Have a great weekend!

Better to use a step up DC transformer - much more efficient and
compact!!

Sea Jay wrote:
Better to use a step up DC transformer - much more efficient and
compact!!

A DC stepup transformer? If transformers worked with DC, Edison would
have won instead of Westinghouse.
krj

Wrong term. A DC/DC converter is what he means. You can get an automobile
power supply brick for most laptops and they are far more efficient than an
inverter and wall wart.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

"krj" wrote in message
...
Sea Jay wrote:
Better to use a step up DC transformer - much more efficient and
compact!!

A DC stepup transformer? If transformers worked with DC, Edison would have
won instead of Westinghouse.
krj

In article . com,
"Sea Jay" wrote:

Better to use a step up DC transformer - much more efficient and
compact!!

there is no such thing as a "DC transformer"......

Sea Jay wrote:
Better to use a step up DC transformer - much more efficient and
compact!!

Hmm. The DC-DC converter b393capt mentioned above is rated 88%
efficient; a typical boat inverter is nearer 95% efficient when running
a smallish load like a laptop. When the wall wart inefficiency is
included, they are comparable, the DC-DC converter is not "much more
efficient."

Mark wrote:
Sea Jay wrote:
Better to use a step up DC transformer - much more efficient and
compact!!

Hmm. The DC-DC converter b393capt mentioned above is rated 88%
efficient; a typical boat inverter is nearer 95% efficient when
running a smallish load like a laptop. When the wall wart
inefficiency is included, they are comparable, the DC-DC converter
is not "much more efficient."

Nor are they very good at absorbing voltage spikes.