Inverter question

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Since the power draw is only about 1/2 of the inverter's capacity, it will probably work ok. With motors, the issue is the inrush current at startup which can be several magnitudes larger than the running current. The bigger the motor the bigger the starting surge.

I have a 320 W continuous / 400 W peak portable inverter/jump pack made by Xantrex. I recently acquired an Empyre Elite 100 boiler (not installed yet) and was playing around / testing. The boiler's temp controller is pretty basic, has a forced draft combustion fan and is rated to draw 2 amps. When I plug the boiler into the inverter and switch the inverter on the power meter spikes to about 250 watts for a few seconds, then settles out to about 190-200 watts once the fan is up to full speed. This particular inverter has a load sensing protection thing. If you try to "start" too much at the same time it will simply not turn on.
 
You may have an issue with the inexpensive modified sine wave inverters vs sine wave inverters in that the circulator may run noisily and run hot. The "chopping" msw is not the same as line power.
 
I have a 600 watt Xantrex prosine that I use to run the whole furnace and pumps. Its rated at 540 continuous, 600 for 5 minutes and 1200 surge. So far it’s run everything with no problem. Tarm Excel, two Grunfos 15-58, and 3-4 Taco 007's. The Kill-o-watt meter shows about 520 max., but I doubt everything will be on at the same time very often.
I went with a pure sine inverter because I didn't want to risk burning anything out on the TARM.
For the extra 20 bucks I'd go with the 300 watt unit over the 180.

Have a look at http://www.donrowe.com/ he has a good selection.
 
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You may have an issue with the inexpensive modified sine wave inverters vs sine wave inverters in that the circulator may run noisily and run hot. The "chopping" msw is not the same as line power.
I thought this one was pure sine...... I will go with something bigger, but for some
Reason I thought I had to go huge.
 
I am using a Xantrex PRO Sine 1000 watt. With everything running I come in at 385 watts (measured watts with a meter). I spent a little more so I can plug in a light. I also have an automatic transfer switch.
 
In retrospect I wish I had gone with the 1000 watt version. It would have given me a larger buffer for only a few dollars more.
 
Yah that was my thinking once you comit to buying one the incrimental cost for getting one bigger then you need to have some reserve power for doing something else is pretty reasonable.
 
I pretty much lived in an rv during the summer months while I was in my 20's.

I powered hundreds of different devices with cheap modified sine wave inverters. I think pure sine wave inverters are overrated. Supposedly laser printers won't work with modified sine wave, and the charger to my palm pilot was not happy either.

The other multitude of devices including microwave, lights, chargers, computers, sound equipment, pumps, furnace, fans, freezer, fridge, coffee maker, power tools etc were all just fine. I had a 2k watt inverter, large battery storage and 200 amp alternator.

Another source for alternative emergency power are large computer uninterruptible power supply. These can often be had for cheap or free once the batteries are bad. Most have 12 volt batteries that can be easily replaced. Plus it comes with a built in charger and transfer switch.
 
I'm going UPS too. Found an APC 2200 VA rack-mount here, NIB. It's new but a few years old. Got a pretty good deal on it - as long as the batteries prove out. Now I gotta gear up a place to put it - the sucker weighs a ton.
 
Test the output voltage of a modified sine wave inverter with your meter and tell me what it reads.
 
Test the output voltage of a modified sine wave inverter with your meter and tell me what it reads.
If you use a fluke 87v or other meter that measures true rms voltage on a modified sine wave inverter it'll read the same as a pure sine wave inverter.
 
I went with a pure sine inverter because a modified inverter won't run the draft fan on my Eko. I wanted a backup that runs the whole heating system. As for computer UPS, I have a UPS 1400 and it ran my system for about 30 mins on frsh batt;s (boiler running w/ 3 circ's running). My inverter w/ 1 deep cell 12 volt batt, runs my system for +6 hrs. Typically when we lose power it is for 1.5-2 hrs. The inverter backup is to cover the system when I head for work. If power goes down while I am at home, the generator comes out.

I don't hate money, I want to feel comfortable when I head for work and my 2 Labs are alone the FOBAR factor is minimal.
 
So I ended up going with the Xantrex PRO sine 600. Got it from donrowe.com for $150
hamabupu.jpg
 
So I ended up going with the Xantrex PRO sine 600. Got it from donrowe.com for $150
 
The transfer switch I made...... The inverter is just an inverter
 
Xantrex does make an automatic transfer switch for it. I plug my furnace circuit into it, so if I do lose power at 2:00 a.m. I can rollover and go back to sleep.

You can't read the labels but the box on the left is house power and the one on the right is from the inverter generator. Once the generator is up and running I can plug into that circuit and I'm good to go. If it runs out of gas it goes back to the inverter battery bank.

battery bank.jpgswitch panel.jpg
 
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Yeah, they were free and I can't pass up free. They were redoing the UPS at work and were going to scrap these out. They were only 5 years old, still a lot of life in them.
 
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