Computer is blinking while used with an inverter in my van :

[pengyou]

I am sitting in my van at this very minute using my wireless internet connection. It is really awesome! but I am having a problem with the inverter. The inverter seems to be switching on and off about once a second, which causes my notebooks screen to go from bright to dim (plugged in settings vs. battery settings). Why is the inverter doing this? Is it a faulty inverter, or is there some other reason? I have used it before for other things and had no trouble.

[lockdoc]

Your inverter is probably not big enough. I can not run my laptop with a 400 watt inverter or the same thing happens. I think I'm able to charge it when it is off but maybe not. I can't remember.

[robertg]

i had a 400 watt inverter a couple of years ago, until my cousin fried it while trying to use it to power an electric drill.

[Rileysowner]

Most laptops use very little power 65-100watts. I would doubt unless you have the most powerful of laptops and the weakest of inverters, that it is not that the inverter is too weak. It could be that the inverter is failing or defective, or the plug into the van might not be seating properly so when you shift a little it momentarily breaks the connection (unlikely). It could also be that your laptop requires a true sine-wave ac power. Most inexpensive inverters don't provide that.

As for trouble shooting:

1) Try the same inverter with the laptop in a different vehicle, if it works you know it is the van's power that is the problem.
2) Try the laptop with a different inverter in the van, if it works, you know it is the inverter.
3) If it does the same thing in both situations, then the problem is the laptop, and likely its requirements are not being met.

[pengyou]

Thanks! The inverter is only a couple of months old, so I will rule out the old part of the equation. The laptop only needs 60 watts and the average for the inverter is 100, with a 150 being a peak. The blinking is cyclical, at once per second, so I think the sine wave thing is the issue. I had never thought of that.

What if I bought a UPS and connected it to the inverter that I have? Assuming that the wattage is correct with the battery in the UPS clean up the electricity for my notebook? I am thinking that the UPS might be good to have in my van for some other things I plan to use - it would absorb the electric peaks and valleys of my toys but should only need a fairly constant stream of juice from the car to the battery.

[lockdoc]

My power cord has a sticker on it stating 90 watts. I know for a fact my inverter is OK. It might have something to do with the fact that I'm taking 12V DC and converting it to 120V AC and then converting it to 18V DC for the laptop. The "blinking" that happens when I hook up the inverter is the inverters circuit breaker going on and off. One thing I haven't tried is to run it with the battery out of the laptop.

[CaptSquid]

I've a 150 watt inverter. The biggest laptop power supply I have is 90 watts. I can even run a 13" TV on that inverter. But I feel safer if I run my 600 watt inverter for anything bigger than the laptop.