Power Inverters

[slowrev]

the inverter might not regulate well with virtually no load on it. Plug in a 100W lamp and check the voltage.

 

[Soundguy]

Depending on what kind of VOM you are using, and what type of output the inverter is producing you can get less than accurate readings. An ossciloscope would be your best bet.

Depending on design and cost.. you can get everything from square wav, modified square wave ( stepped ) modified sine, or true sine wave output.

Depending on what type of power supply your laptop uses, there may be no ill effects. Say for instance.. the laptop used a regular ac transformer and drifge/filter .. just about any output would be fine... that square wave ill be worked over by coil inductance and smooth it quite a bit.. won't matter by the time the wavefrom gets flopped and filtered. Average power will probably be -worst- with straight square wave..

A power supply using triacs , depending on how well built will work decent with modified sine or sine wave.. but will also be very tolerant of low voltage. On the test bench, using a variac xformer.. I've fed 90vac line feed to some switching power supplies with very little effect to operational abilities of the computer...

What type power supply is it? Is it possible to just use a regulated dc to dc adapter? ( what voltage does it use? )

Soundguy

 

[slowrev]

Good job Soundguy! Did not know there were any more electronic persons on here that actually knew how the innards worked.

 

[Bob_Skurka]

OK Soundguy (since you are one of the guys who so soundly beat me about the head when I was considering the inverter on my tractor and your little pinky finger obviously knows more about electricity than I ever learned) Here is my question . . . every summer we go to Florida and my daughter uses a laptop to watch movies in the back seat while we drive. I have a 300 watt el-cheapo inverter and I have the iGO Juice unit which is recommended by several computer companies. Both will power the laptop.

Which is the SAFER/BETTER choice?

 

[Soundguy]

/forums/images/graemlins/crazy.gif I hope I didn't go off on you too much.. I'll have ta watch that.. lest the mod's get me. /forums/images/graemlins/shocked.gif

Assuming both units are rated for the output for the laptop.. I'd choose the one that was most efficient.. I.e. that used the least power from the 12v side of the vehicle.

I'm not familiar with the igo juice .. so without knowing how it operates can't comment on it specifically... However that said... most inverters I've seen are power hungry.. and not real energy efficient.

Look on the packages and see with the input requirements are for both units, compaired to the output capability... choose from there.

As for safety? both are UL listed right? I'm -guessing- they are both safe to the user.... and like I said in the previous message... without knowing specifically what power supply type the laptop is using.. hard to determine how the output of the inverter is reacting with the input on the laptop power supply... ( My guess that if both units are within a couple years old.. they would be fine together.. ).

Sounds like the igojuice is more efficient...

Soundguy

 

[Soundguy]

</font><font color="blue" class="small">( Good job Soundguy! Did not know there were any more electronic persons on here that actually knew how the innards worked.
)</font>

I was in college for EE before I switched over ( sold out? ) to CE as the general contractor I worked for wanted someone trained in CE..not EE.. and he offered to finish paying the last two years tuition.. so i caved in..

I really wish I would have stayed EE... I'm a hardware guy at heart. At home.. nothing gets thrown away that can be fixed or scavanged for parts..

Soundguy

 

[slowrev]

Soundguy,
I am a CET, however I have not worked for money in that for several years. And I DO know about collecting Electronics junk /forums/images/graemlins/smile.gif Howerver how do you fix a walkman or diskman ??
I sort of sold out too and have moved into computers and programming, it sure pays a lot better /forums/images/graemlins/smile.gif

 

[Soundguy]

</font><font color="blue" class="small">( I sort of sold out too and have moved into computers and programming, it sure pays a lot better )</font>

Boy does it. As my 'night gig' I work at a local media company and do sound engineering for bands. Lot easier.. more pay... ( free entertainment.. )

</font><font color="blue" class="small">( several years. And I DO know about collecting Electronics junk )</font>

Easy! throw it in the 'scavenge pile', and get another one for 9.99 at wallmart. I usually do pop them apart to see if ti is an easy fix.. cold solder.. easily identifiable bad component.. but more and more everything is surface mount... too hard to work on without 25K$ of test equipment... Later when i need a capacitor or transformer for a project.. I just go to the pile of goodies and extract what I need...

Soundguy

 

[gotrocks]

Hello Soundguy,
Thanks for sharing your knowledge.
<font color="blue">What type power supply is it? Is it possible to just use a regulated dc to dc adapter? ( what voltage does it use? )
</font>
It is a Vector MAXXSST 350 watt. Book says "modified sine wave has an RMS(root mean square) voltage of <font color="red"> 110 volts,</font> which is the same as standard household power.
I haven't pluged in my laptop yet, but I can stall my 3.5 amp <font color="red"> 120 volts </font>drill with just a little squeeze on the chuck. It will run but not much umph.
My volt meter indicates 117 in the house socket. Is the voltage difference what makes the drill weak? Is the formula volts/amps = watts?
Thanks again for your additional input.
Norris

 

[ljh2]

</font><font color="blue" class="small">( Is the formula volts/amps = watts?
)</font>

Nope,
Using:
P - Power (watts)
V - Voltage (volts)
I - Current (amps)

The formula is: P=I * V

/forums/images/graemlins/smile.gif