Expedition XJ Build, Tech & Sources Thread

[outlander]

Subscribed....

 

[yossarian19]

I used to have a 750 watt inverter (if memory serves) and it wasn't sufficient to run my laptop. Using it while plugged in would overload the inverter in pretty short order.
That being said - 400W should be plenty to keep a small device happy or charge a laptop provided it isn't in use at the time.
Just think about the largest device you are likely to use and make sure that you size your inverter accordingly. 400 watts at 120 volts AC is 3-and-change amps. 800 watts should be enough to run an angle grinder. Do you need that much?

 

[Bdiddy11]

So what I'm understanding from the article on the iPad as a Nav unit is that if it's the 3g unit it has a built in GPS which can/will connect to satellites outside of 3g coverage via the GPS chipset.


We're planning on getting an iPad 2 but not use it on a network. So in order for it to be a good Nav unit, we'd need to get the 3g version but not actually use the 3g...

 

[X E Ryder]

$29 is a deal! so 400 watts is plenty? i dont know much about inverters yet. saw the 800 for $17 more?

It really depends on what you want to run. A 400w can draw 30 amps DC, so you are going to be running a 10 gauge wire to it, go up to 800w and you are talking about drawing a peak of around 60 amps, running 6 gauge wires, and actually putting that sort of demand on your battery will discharge it quickly when the engine is not running.

I used to have a 750 watt inverter (if memory serves) and it wasn't sufficient to run my laptop. Using it while plugged in would overload the inverter in pretty short order.
That being said - 400W should be plenty to keep a small device happy or charge a laptop provided it isn't in use at the time.
Just think about the largest device you are likely to use and make sure that you size your inverter accordingly. 400 watts at 120 volts AC is 3-and-change amps. 800 watts should be enough to run an angle grinder. Do you need that much?

If you figure that 400 watts / 110 volts = 3.6 amps this should give you an idea what you can power continuously, with a 7.2 amp surge rating. The higher your battery voltage, the more effective your inverter will be against sags to the input voltage caused by starting of your load. So idling your XJ when attempting to power larger loads with both keep your battery up and provide a higher tolerance to a full load.

For example, I can run my shop vac on my 400w inverter, and the vac draws 4 amps according to the label, but if I try to start it with the engine off (12.7 volt battery at rest), it trips right out on overload. Do the same thing with the engine idling (14.2 volt battery charging) and it bellies right up under the load and works fine.

The specific reason I chose 400w is it will easily run my Makita lithium ion battery charger, for which I have cordless impact guns, saws etc for most any remote location power tool need. My laptop charger indicates a 1.6 amp draw at 120 volts AC, so that's another no problem. I also charge my cordless inflator which falls well below that.

Just check the specs of the device you care about running, and make sure your inverter wattage is enough. Remember once you get up to the 1000w range, you should just grab a Honda generator to take along - fuel efficient, quiet and self contained for those bigger loads.

Each inverter has an efficiency curve associated with it something like this:

The short version is, it costs roughly 10 amps DC of battery draw to make 100 watts of AC power, or roughly again, 1 amp AC. Once you start laoding down the inverter, the power factor or efficiency starts to suffer and it heats up and finally trips the overload circuit. You load it, the input voltage sags, the output demands more current to keep up, the friction heats up the circuit causing further losses, and it trips.

Whew that's exhausting! My opinion and method has always been, put in a 400w inverter and if you need more use a portable generator. :idea:

 

[Vanimal]

I used to have a 750 watt inverter (if memory serves) and it wasn't sufficient to run my laptop. Using it while plugged in would overload the inverter in pretty short order.
That being said - 400W should be plenty to keep a small device happy or charge a laptop provided it isn't in use at the time.
Just think about the largest device you are likely to use and make sure that you size your inverter accordingly. 400 watts at 120 volts AC is 3-and-change amps. 800 watts should be enough to run an angle grinder. Do you need that much?

odd, i use my laptop on my 400 watt inverter all the time. in fact, i run my router, modem, and laptop off of it and a deep cycle marine battery when the power goes out, till the battery dies, which takes a while. 120volts x 1.6amps = 192watts for the laptop.

 

[dsapper]

I got this one from amazon for under a 100

http://www.amazon.com/gp/product/B000KK295Y/ref=ox_ya_os_product

It was the largest one I could find that fit under the passenger seat. Its 1250w. I've run dual laptops, dremel, charged drills, even a circular saw off it with no issues ever.

I do have it hooked up with 0gauge and some massive fuses to a large yellow top optima, but I love it.

 

[djlarroc]

Thank you guys for the explanation! 400w is plenty for me then. I'd only want to charge a laptop, ipad, or etc, but not necessarily run it of the inverter. 400w would be plenty for me.

 

[dieselenthusiast]

odd, i use my laptop on my 400 watt inverter all the time. in fact, i run my router, modem, and laptop off of it and a deep cycle marine battery when the power goes out, till the battery dies, which takes a while. 120volts x 1.6amps = 192watts for the laptop.

X2, I have a Schumacher 410 Watt Power Inverter. It comes with a cigarette lighter adapter and alligator clips.

Maximum Continuous Output 410W
Surge Capacity 820W

 

[X E Ryder]

iPad 3G DOES Nav without 3G, Just Need Satellites

So what I'm understanding from the article on the iPad as a Nav unit is that if it's the 3g unit it has a built in GPS which can/will connect to satellites outside of 3g coverage via the GPS chipset.

We're planning on getting an iPad 2 but not use it on a network. So in order for it to be a good Nav unit, we'd need to get the 3g version but not actually use the 3g...

OK, I wanted to test this before replying. Even though the iPad Nav Primer article claimed it, we went out yesterday and recorded a nav track as we ran our weekly errands. It is mountainous and lots of 3G null zones.

The track recorded perfectly except when we were in a steep canyon and the GPS signal was lost - tracking worked fine in the areas with no 3G though.

Here is an excerpt from Apple's own technical specs document on the iPad 2 3G that helps clear up the confusion and why we have it: "The iPad 2 Wi-Fi + 3G models do have built-in GPS chips that receive signals from the global GPS satellite system to determine your location - as closely as three meters, depending the the number of satellite signals the chip is receiving. GPS in the iPad 2 is classed as assisted GPS, also known as AGPS, which enhances the performance of standard GPS in devices connected to Wi-Fi or the cellular network. The iPad 2 W-Fi + 3G may be used for the full range of apps that require detailed location information wherever you may be on the planet, including mapping, driving, services locators, and more."

I think the confusion often arises because the WiFi iPad will use maps and provide your approximate location when connected via WiFi.

The 3G iPad will check the internet database of topo data against your iPad's current GPS readings to help provide more accuracy to your readings, when signal is available. That is what Assisted GPS is, and bear in mind the uses for it are many, one key example is if you plan a route, and have a 3G connection, it will check weather and traffic databases to provide the best route, not just go strickly by a map provided a couple years ago.

Hope that helps.

 

[Sardog1]

XE, do you use the inverter to charge your iPad while using the nav app? When I plug my iPad 3 into the cigarette lighter, it says "not charging". Figure the cig lighter doesn't provide enough amps for the iPad to charge. I have both Motion GPS HD and Drive. Fantastic apps but don't trust what they show as posted speed... It's wrong more than its right! Other than that they are really nice.

 

[Sardog1]

Found my iPad charging issue. You need to have a car charger with at least 2.1 Amp or it will not charge. The cheapo one that I had was rated for ~1.0 Amp. Worked great for the phone but not for the iPad. Now when plugged in, it doesn't come off of 100% full charge.

 

[X E Ryder]

Charging & Using iPad

XE, do you use the inverter to charge your iPad while using the nav app? When I plug my iPad 3 into the cigarette lighter, it says "not charging". Figure the cig lighter doesn't provide enough amps for the iPad to charge. I have both Motion GPS HD and Drive. Fantastic apps but don't trust what they show as posted speed... It's wrong more than its right! Other than that they are really nice.

We usually have the iPad connected to our Pioneer head unit, and either listening to Pandora or the playlists in the iPad. You can control music within Motion X GPS HD which my wife likes because she never leaves the app to adjust music.

The Pioneer CD/Tuner/Aux/iPod deck provides 1 amp of charging via USB. I don't see the deck model I have on Pioneer's website anymore, but a closely featured unit would be this one...
http://www.pioneerelectronics.com/PUSA/Car/CD-Receivers/DEH-2500UI

We have found that like most GPS', your speed is best used as a reference only. Consider that you have 3 or more satellites in space triangulating your position and basing speed off the micro changes you are making. It seems like it gets more accurate the faster you go, because there is better measurable movement, but that is my opinion.

The Motion X app is really good; be sure to try all the different maps, and do the tutorials - it really is a powerful app!

 

[X E Ryder]

Receiver Vise From Mac's

Another handy tool to have along on your exploits is a receiver hitch vise. This one is made by Mac's, and is double drilled so you can rotate it anyway you wish in 90o increments andpin into place. It opens wide enough to do a u-joint, has an anvil surface, comes with a stowing handle and pin with cotter. I have only used it a few times, but it was just the ticket when I needed it - few things replace a vise when you really need to hang onto something. Found this on Quadratec.

 

[kndrewa]

yeah man, I've wanted one of those forever!
Did a quick google and it didn't turn up.
Let me know if you have a link.

 

[SpeedyVic]

yeah man, I've wanted one of those forever!
Did a quick google and it didn't turn up.
Let me know if you have a link.

http://www.macscustomtiedowns.com/product/TrailD-Vise/All

 

[X E Ryder]

yeah man, I've wanted one of those forever!
Did a quick google and it didn't turn up.
Let me know if you have a link.

Here you go bro

http://www.quadratec.com/products/product_search.php?kw=vise&submit=Go

 

[kndrewa]

THANKS! I watched the video on their website, and it looks like the inner part of the vice extends pretty deep. I wonder if that might interfere with the gastank?

 

[X E Ryder]

THANKS! I watched the video on their website, and it looks like the inner part of the vice extends pretty deep. I wonder if that might interfere with the gastank?

Well if you note, I have the JCR bumper; the receiver is up inside of it and I have the OEM gas tank skid - still has plenty of room behind. I don't think it will be an issue even on a bumper that resides a closer.

 

[kndrewa]

Okay, great, guess I don't have any more excuses for not having this.

 

[djlarroc]

received my spectre kit yesterday...

also picked up some 33x10.50 bfg at, that may replace the 245/75 MTRs..

tire fits in stock location too.