Check your inverter!

[Ed Johnson]

I thought my inverter was working fine... it ran what I plugged into it ok. But, I happened to check the voltage with a good voltmeter and it was only putting out 75 volts AC (should have been 120).

Check your inverter before it fries a laptop, mifi or some other expensive equipment.

Have a nice day...

 

[Rob Wadsworth]

What make/model of inverter are you referring to?

 

[Jason Russell]

If you're running anything critical/expensive off an inverter, I strongly recommend spending the few extra $$$ to get a pure sine inverter. While the square wave inverters are great for a budget, they are not great for any sensitive instrumentation.

 

[Dan Robinson]

Most inverter problems can be fixed by using a larger inverter (750 watts or greater) and direct-wiring it to the battery with a dedicated (and fused) circuit using large-gauge wire.

The 400 watt or smaller inverters are unreliable for powering laptops, and cigarette lighter plugs are prone to big voltage drops and eventual contact wear.

 

[Ed Johnson]

I run my laptop and mifi off 12V DC, I rarely use the inverter... but it's handy when I need it though.

 

[Skip Talbot]

I run my laptop and mifi off 12V DC

As do I. Seems a waste to go from DC to AC and then back to DC again to power the laptop. I often get some issues with noise attempting it too. There's some stuff I need the inverter for, however, like the 22" monitor I put in the van and toaster oven (just kidding on that last one).

 

[STexan]

I recommend going on Amazon and find an automobile DC adapter built especially for your particular laptop. The relatively small batteries in automobiles are not very conducive to powering anything but the smallest inverters, especially at idle, and especially if pushed to their limits for long periods. Class 8 truck fires occur with ever-increasing regularity due to over-loaded and/or improperly installed inverters. I operate as old-school as possible so for me, not having an inverter is not a problem and if you have a bunch of AC powered devices while chasing, perhaps you need to rework your setup before you're vehicle and equipment goes up in flames.

 

[Ed Johnson]

I only use 12 vdc in my auto now. Had the inverter for years.

 

[Shane Adams]

The 400 watt or smaller inverters are unreliable for powering laptops, and cigarette lighter plugs are prone to big voltage drops and eventual contact wear.

That's what I've been doing my whole life. Now that we only occasionally use it for emergency backup when the scanner/phone batteries run low, I don't think we'll have any issues. But we powered a laptop off it for two seasons with no issues.

 

[David Wolfson]

I have my a/c devices attached to a plug-strip through an inexpensive Kill-A-Watt meter to the inverter. The meter can show RMS voltage, power-factor, Amps, Volt-Amps, and such. In-use tips: connect the meter to the inverter with a short extension cord and have a little USB-powered light or flashlight handy so you can read the non-backlighted meter at night.

 

[Dan Robinson]

I don't know why I've had such bad luck with the smaller inverters, but every one I've used has had problems. Right now I have a 400 watter that is supposed to be my emergency backup, but it wouldn't even power my Cradlepoint router when I tried to use it in my parents' car when they were here visiting.

The 750 watters I've used since 2004 (9th year now) have been virtually flawless when connected to the battery. They never get hot, and I've only had one fail in 2006 when I had a car-full of people with laptops and chargers. The replacement one I bought in 2006 is still working to this day after being installed in its 3rd vehicle. There's no reason to believe they are unsafe to use, particularly when operated well below their rated capacity.

On a typical chase, my inverter is powering the laptop, two camera chargers, a cellphone charger and the cradlepoint router. WxWorx and the dashcams are direct DC. I guess I could spend a couple hundred on DC adapters for every device I have, but since what I have has always worked perfectly, I don't see the need to spend the money.

 

[STexan]

Nobody is saying small inverters don't [sort of] work to charge and run some smaller laptops and devices with relatively small ac power wattage needs. The question is how long can you continue to push your luck. Furthermore, some ac/dc converters will run on square wave power that the less expensive units output, but they don't necessarily like it. I belong to a truckers forum and every 5 to 6 weeks there is a new posting of a truck that burned to the ground where the inverter was ruled as the source of the fire and invariably they either had an inexpensive small inverter or the typical load was just below or above the peak wattage rating. And big truck charging/battery systems are much more suited to handling inverters than automobile charging/battery systems Be careful with inverters and don't cut corners with them and monitor them closely for excessive heat buildup is all I'm saying. Properly sized and professionally installed [from the batteries] inverters aren't cheap but they are worth it if you have to have on-board ac power.

 

[Jeff Snyder]

I had a ~750 W inverter from 1999-2010 that worked very well for me, but it bit the dust halfway through the 2010 chase season. The one that I bought as a replacement is rated similarly, but it's very, very noisy from an RF standpoint. Whenever the inverter is on, my ham radio is much less useful with significantly more noise (e.g., with the inverter off, I can hear stations just fine; with the inverter on, I just get static). I've tried to keep the antenna coax as far away as possible from the inverter and its cables (both the DC power cables and the AC extension cord connecting a surge protector in the front seat with the inverter in the trunk). This has helped a little, but I still turn off the inverter every time I need to transmit on the ham or when I want to listed to a station with a relatively weak signal. It's a major pain in the butt, and I've thought about building a cage to place around the inverter in hopes of squashing some of this RF noise. I've checked the ground and all other connections, and they're all solid, so I'm not sure why this particular inverter is so noisy.

I'd really like to have a pure sine wave inverter, but I can't justify the cost with how much I use it (pretty much only during chase season).

 

[Jason Russell]

Square wave inverters push a ton of noise down the ground path. Some of the expensive square waves use a big capacitor across the poles to squash the noise.

 

[David Drummond]

I think one of the biggest problems is running inverters (even smaller ones) long term through the cigarette/aux power outlet. If you ever took the panel off and looked, the wire gauge running to most of those is extremely small, and meant to only perhaps charge a cell phone or other small device. Not to run multiple devices hooked up to it and certainly not power inverters. What eventually happens is someone gets enough stuff plugged in there, it pops the factory 10-15-20 amp fuse, and they throw in a nice big 30A fuse in there so it won't pop again. Problem is, the original fuse was rated for what that wire could handle before melting, and when you put a bigger fuse, it allows more power than the wire can handle and the fire potential goes WAY up. That original fuse popped for a reason. The circuit was overloaded and it was doing it's job. As has been said, the preferred hookup is straight off the battery when using an inverter for any extended length of time.