power inverter advice

Well, I'm impressed, and even modestly informed, Haulin. I just spent 4 low income years designing solar systems, which use inverters to convert the DC system output into AC power. Actually, the SMA/Xantrex/Outback and other true sine wave inverters make cleaner, more uniform, and lower surge power than commercial power. Devices and appliances do run better, use less power, and last longer. That being said, I will check on my Powerdrive 1,500w inverter for type. I guess I'm just an ol' chunk of coal, though. I bought 4 new batteries at Fleet Pride and a Koolatron refrigerator which turns itself off when it reaches the temperature setting. Other than that? I just disconnect my ground cable for extended absences, take my food with me, (I would never leave anything running when I'm away from my truck for extended periods of time) and have more weeks with start power than I'll ever be able to take off from Driving For Dollars. I do have to reset my satellite radio when I get back, but that is free and easy, and not too annoying.

Good advice on wiring, routing, and protection. I did most of that, and I've seen that auxilliary battery bank you speak of. The guy who had it was very strong on how useful it is, but his main battery bank was so corroded, so mismatched, that I was forced to add some BS factor to his comments.

That is it for me, except that I remembered something. If your batteries are mismatched in type, if they're varying ages, or if they have different voltage designs (an unbelievable amount of design variation in deep cycle or storage batteries: truck batteries) My truck, and I, really are pleased with our 4 new 950 cold crank amp batteries. I use dielectric grease on all my terminals now, since Freightliners are so prone to corrosion and I don't like dealing with that. About once a quarter I take it all down and wire brush, re-grease, re-torque all my terminals and connections. So far, so good. Thanks, Haulincars.

 

I bought modified sine wave a few years back. Works fine but I have to turn the squelch way up on my CB. My next one will be true.

 

Don't have time right now to look up there secs on each but I can tell you that Xantrex usually makes good stuff. I'm not familiar with the Solar brand but that is not necessarily in and of itself make it not a good unit.

I will say that if your going to get a modified unit the better quality it is the better off you'll be in the long run but still not in the same league as a true unit....

Hope that helps..

 

I am GUESSING here but it sounds like your new microwave is telling you that it does not like a modified wave unit and (again GUESSING) that's what you have. If you have the make/model of your inverter you can look it up and in the specs it will clearly tell you if it is modified or true. Again, only guessing but there are several APU design theories, (Meaning the way they were designed to work). It sounds like yours may not have a 110/120vac generator but instead puts out a decent amount of 12vdc to charge batteries and run an inverter. Or it is wired to the truck in a way so that the built in generator is not used (if it has one) but is wired to always use the inverter to supply 110/120. Lots of variables here. Bottom line though it the microwave you now have will not function with the system you now have.

It sounds like your a company driver and are stuck with the system so likely your only option is to get a different microwave and see if it will work. If you can drive the tractor to the store and tell them you need to test it in your truck on your trucks power system before you buy. If they say no be sure they have a liberal return policy (like Wallyworld) so you can buy it, test it and return it if needed.

If your not limited by not allowed to change equipment you could change the inverter (or install a 2nd one) that will run the microwave.

Also... after reading the rest of this thread one of the other respondents noted (Correctly) that a 700 watt microwave does not take 700 watts to run. That is the rating of the output of the radiation element, (AKA: cooking watts or cooking power). The 110/120vac requirement is certain to be a different number, also (usually) listed in watts. Look on the back or bottom of the unit for this number. It is possible that your inverter just wont provide enough for it to run but I'm guessing this is not the case because if overloaded most inverters can provide (for at least a short time) over their rated output. exceede this surge time or the max limit and they usually shut off completely returning to service after you reset a breaker, or they may have an internal timer or a heat type "fuse" that will reset itself eventually. Again, they are all designed differently.

Hope that helps...

 

Well... Yes and no....

Yes it is the inverter that kills the batteries. The rate at which it does so is directly related to the load you put on it, most of the time. (Assuming no charging is going on.) Meaning, the more stuff you try to run the faster the batteries drain.

Not so much about the not using any power just to be turned on part. Every inverter has what is called a "No load drain" or "Standby drain" or something very similar to that title. The better inverters keep this number very low. Some are as low as a single amp or so which is essentially insignificant. This is sort of like the draw your home TV uses waiting for you to aim the remote at it and tell it to turn on. In order for it to receive that signal some part of the TV must be on (and using at least some power) otherwise the remote signal would reach a dead receiver and nothing would happen. As I said, some are better at keeping this draw low than others. I have see one that was over 30 amps of standby drain. That is pretty significant! This is a rating that is not always easy to find. It "Should" be listed on the specification sheet for the unit but I have had to contact the manufacturer more than once to find out what it was prior to a purchase. With the unit in hand it is easy to measure with an accurate digital meter if you have one and know who to connect/use it.

Of course if you use the manual switch to shut off the inverter should then have zero draw.

Also, there are some inverters that have cooling fans that run whenever the inverter is turned on, not just when it gets hot. Obviously this will cause a draw. If you spend any time in computer component catalogs you'll see there is a huge difference in the power consumption numbers of these little cooling fans, (as well as a huge difference in quality of the fan motors and bearing types). Even if the fans only run when the unit is hot, if they are cheap ones and draw a lot of current that is just draining your batteries all that much faster. Also, the fans are taking some of the capacity of the battery cables that bring the inverter it's power from the vehicle. Although when compared to the power draw needed to supply the transformers inside the inverter the fan draw, even for cheap fans, is minimal but it is still a factor in battery drain. All these things and far more go into making any electronic device more or less quality.

Another thing people generally fail to realize is that the hotter the inverter gets, the less efficient it gets. Coop it up in a small un-vented compartment and run it hard and it will get plenty hot, even with its fan running. This will cause it to use a lot more 12vdc power than it should. It will also greatly shorten the life of the inverter. This also means that you need to make sure nothing like a jacket or rags or whatever are allowed to cover the unit. Of course this (not covered up part) should be obvious and common sense for any sort of device that has cooling fins on it, but as my Grandpa used to say, "Common sense ain't always all that common".

Hope this helps.

 

Thanks for the compliment!

I forgot about Outback, most of their stuff is pretty good too. Like the others I mentioned, not the least expensive but you get what you pay for... If your lucky. One thing you almost never get is more quality than you pay for, that's for sure!

Another excellent point was made here about the batteries. In a bank of batteries, (a bank is anytime you have one battery attached to another one or more) mismatched ages, sizes or construction types is never good for the individual batteries, therefore it is not good for the entire battery bank. There are several reasons for this that for sake of sanity and space I won't go into here, just understand it is always bad, never good. In a bank I never replace just 1 battery unless I'm selling the vehicle or I'm just trying to get by for a temporary period. This goes for vehicles, flashlights, TV remotes, those toys your wife has... Any battery bank.

Along with battery matching (as Starboy noted) keeping the battery terminals and connections clean and tight is very important to battery life. And Like I said before, quality "ends" on your cable that have been properly installed. I always water proof mine to prevent corrosion inside the terminal itself. I am talking about the end of the cable, not waterproofing the connection to the battery. Dielectric grease is great advise too! In addition to the battery connection, when installing cable ends, I put it inside the terminal using enough that excess squishes out, properly crimp the terminal then install a heat shrink tube of the type that has the "goo" inside it. This both seals it from water/vapor but also helps with the mechanical strength of the connection. I do this on almost everything electrical I install, not just battery cables. Doing this makes everything work better and last longer including the batteries, cables, starter motor, brighter headlights.... everything that uses electricity is better and longer lasting.

As always, I hope this helps.

 

If you have a TV and Microwave plugged into your inverter they are using power even though nothing is turned on. The microwave is either displaying the clock or waiting for a command and the TV is probably instant on. That means the inverter is using power.

 

Yup, great point. You have to look at peak draw. There was a large discussion about this in the Cooking in the Truck thread.

All these fellas are dead on OP. You're lucky to have 'em.

 

Where can I get a pure sine inverter? I've tried a couple major retail stores but all they have is modified? Besides online I do otr alot I'm on the road at least 1 month on the road that's why I haven't gotten it online..... thanks

 

I got a 2500 watt cobra from amazon back in March 2013 for $169