power inverters
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Joined: May 2002
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From: tampa, FL
Vehicle: 2000 Tiburon
power inverters
so im looking at power inverters here > http://www.tigerdirect.com/applications/category/category_slc.asp?Recs=10&Nav=|c:237|&Sort=3
would a high power inverter, lets say that 1200w Whistler, be ok to run in a VW Jetta 2.5? or even my 2000 Tib ? would those alternators be able to handle this inverter if i were to actually use up 1200 watts worth of power ? or would i fry my alternator quickly?
would a high power inverter, lets say that 1200w Whistler, be ok to run in a VW Jetta 2.5? or even my 2000 Tib ? would those alternators be able to handle this inverter if i were to actually use up 1200 watts worth of power ? or would i fry my alternator quickly?
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Joined: Sep 2001
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From: Pflugerville, TX
Vehicle: 2000 Elantra
WTH are you doing? A welder really calls for a truck, you know . . .
The alternator is rated for what, 90A? 90A * 12V = 1080VA. If you had a *constant* 1200W load, it would kill your alternator in a pretty big hurry. Don't forget it also takes power to run the car.
The alternator is rated for what, 90A? 90A * 12V = 1080VA. If you had a *constant* 1200W load, it would kill your alternator in a pretty big hurry. Don't forget it also takes power to run the car.
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Joined: May 2002
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From: tampa, FL
Vehicle: 2000 Tiburon
im thinking a small fridge, not like an mini fridge, but one of those cooler style fridges, a laptop, and 2 cell phones, i guess i could just add up the wattage of each and determine a reasonable size inverter based off that. no ?
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From: seacoast (New Hampshire)
Vehicle: 01/hyundai/tiburon
alot of inverters are iffy with their power ratings...
i got a 200w rms 400w peak inverter that wouldnt even charge a cell phone when i was driving at like 3k rpm...
i got a 400w rms 800w max inverter and it wont charge my laptop... the power supply says 65w...
in the manual its got a bunch of warnings about plugging in different transformers, and for maximum output to wire it directly to the battery.
im about to get a 1000w one myself, because i dont really care about efficentcy i just need my stuff to work...
although i have no idea how long before my chargers would break.
if someone could shed some light on the situation it would be great.(the 400w inverter has a digital volt readout and it drops to under 12v before it dies...)
i got a 200w rms 400w peak inverter that wouldnt even charge a cell phone when i was driving at like 3k rpm...
i got a 400w rms 800w max inverter and it wont charge my laptop... the power supply says 65w...
in the manual its got a bunch of warnings about plugging in different transformers, and for maximum output to wire it directly to the battery.
im about to get a 1000w one myself, because i dont really care about efficentcy i just need my stuff to work...
although i have no idea how long before my chargers would break.
if someone could shed some light on the situation it would be great.(the 400w inverter has a digital volt readout and it drops to under 12v before it dies...)
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From: Pflugerville, TX
Vehicle: 2000 Elantra
Why would you waste power by converting it from DC to AC and back to DC? All those things you listed can be run off straight DC with the proper converters/adapters, or else there is a product designed to run off 12V directly. For fridges look into catalogs for recreational vehicles. Phones and laptops shouldn't be too hard to arrange car chargers.
No, loads are not additive. A fridge will take most power when it is cooling, and very little when it is not. A computer will use power when the hard drives are spinning, the screen is bright, and the processor is going like mad . . and just a few watts when playing your .mp3s. A proper engineer adds up worst-case power consumption and adds a safety margin. A regular user will probably be fine with much, much less than that. Phones are almost not worth considering in this question.
No, loads are not additive. A fridge will take most power when it is cooling, and very little when it is not. A computer will use power when the hard drives are spinning, the screen is bright, and the processor is going like mad . . and just a few watts when playing your .mp3s. A proper engineer adds up worst-case power consumption and adds a safety margin. A regular user will probably be fine with much, much less than that. Phones are almost not worth considering in this question.