Running Inverters 24 Seven

silvertop · April 2011

Just wanted to know how many, that are off grid, run their inverter 24/7? I have been running a SW 2000 for the day, and a small sinewave 180 watt at night for the small idling loads . This works; I was just trying to save wear and tear and some electrical loss at night, but I am beginning to wonder if this is really worth it? My sw 2000 has a tare loss of .6 Amps; just pinching amps I guess!!!:p

mike95490 · April 2011

Re: Running Inverters 24 Seven

I don't believe in wearing out the off/on switch. My XW6048's been on 24/7 to keep the ozone generator for the drinking water running, and the fridge. Can't let the tri-tip get warm !

BB. · April 2011

Re: Running Inverters 24 Seven

Actually, your SW 2000 has a tare load of <5watts (~0.4 amps) in search mode...

I could not find anything else, but it would not be unusual if it drew 20 watts or more when "on" and supplying loads.

Running a small inverter at night to charge a phone, run a laptop, and a few lights---May save you 10-15 watts (or more) times 10 hours a night. So, depending on the overall size of your system, it may still be a significant savings to run the small inverter at night/for small loads.

-Bill

SCharles · April 2011

Re: Running Inverters 24 Seven

Our Trace 2512 [2500 w/12 v.] has been running 24/7 for roughly 20 years. I have had it turned off a few times to change wiring, etc., but only for a few hours.

This is a modified sine wave model. It is located indoors. Never a problem. I have read that Trace, now Xantrex, has begun having the parts made in China and assembled in N. America. Hope that does not mean the newer inverters are not the same heavy-duty quality.

Dave Angelini · April 2011

Re: Running Inverters 24 Seven

silvertop wrote: »

Just wanted to know how many, that are off grid, run their inverter 24/7? I have been running a SW 2000 for the day, and a small sinewave 180 watt at night for the small idling loads . This works; I was just trying to save wear and tear and some electrical loss at night, but I am beginning to wonder if this is really worth it? My sw 2000 has a tare loss of .6 Amps; just pinching amps I guess!!!:p

Three months of winter for search mode. The rest of the year it is on. Saves about .75kwh to run in search for us. The SW's are a little better than the XW in search.

PhilS · April 2011

Re: Running Inverters 24 Seven

For many years (15?), our Heart Interface MSW was 'on' 24/7. I only replaced it to get TSW for our refrigerator (3 or 4 years ago) and now that Magnum 2812 is 'on' 24/7 (not 'search), with another identical Magnum normally in 'search' except when some lights and/or entertainment are on.

I have another Xantrex SW2512 that has been operating in 'search' for maybe the last decade or longer, now providing power for water pumps (pressure and submersible).

silvertop, I don't know the size of your battery bank nor your personal habits, but are you saving enough power to make the extra effort worthwhile? (Example: when turning off the TV & satellite after Jay Leno, the last thing I wanna do is hike 75 ft to the building that houses the inverters).

Making sure the inverters go to "search" is important for saving power. The one I have that remains "on" is that way because the fridge electronics must have continuous power otherwise it goes into defrost mode as soon as power is reapplied, each and every time... and THAT really uses excess power.

Where I wonder if I'm wasting power is leaving three outbacks CCs and the Xantrex inverter LCD displays "on" all the time. Someday I'll ask boB if those displays use any significant amount of power.

silvertop, does your battery bank go into float every sunny day?

Phil

niel · April 2011

Re: Running Inverters 24 Seven

"The one I have that remains "on" is that way because the fridge electronics must have continuous power otherwise it goes into defrost mode as soon as power is reapplied, each and every time... and THAT really uses excess power."

phils,
as a side question, what make and model frig do you have that does that? i can understand your leaving it out of search for that reason as i've seen mine really suck up some amps when it went to defrost. >100a at 12v. lucky for me it was only for about a minute. what kind of power and time factors were you looking at for that defrost cycle?

PhilS · April 2011

Re: Running Inverters 24 Seven

niel wrote: »

"The one I have that remains "on" is that way because the fridge electronics must have continuous power otherwise it goes into defrost mode as soon as power is reapplied, each and every time... and THAT really uses excess power."

phils,
as a side question, what make and model frig do you have that does that? i can understand your leaving it out of search for that reason as I've seen mine really suck up some amps when it went to defrost. >100a at 12v. lucky for me it was only for about a minute. what kind of power and time factors were you looking at for that defrost cycle?

It's a Kenmore 18cf 106-77929700. It was the most energy efficient model I could find. I found that the fridge would allow the inverter to go 'standby' but wouldn't ever bring it back out of 'standby'. As soon as any other load brought the inverter to 'on', the fridge would then start a defrost cycle and continue on as normal, until the inverter went into 'standby' again, and the cycle started over.

If I measured the watts for defrost, I don't remember the reading. Normal running, the fridge uses 100 watts half the time, and zero watts the other half. (300 watts comes to mind, but my memory isn't as good as it used to be... and it used to be crappy :roll: )

Phil

Ralph Day · April 2011

Re: Running Inverters 24 Seven

I also run an SW4048 24/7. Starting out I had a small msw inverter to run some always on loads (pvr, some fans), but found that it only saved 50watthrs per day doing so. Rough calculations and estimations, but not having the sw on search saved some problems: clocks that flashed...central vac would do it's zoom/start/stop when each cycle on search happened (elbow in the ribs...go unplug that!)

I think search would be ideal if your application was intermittent, like a cottage not under constant habitation.

Ralph

petertearai · April 2011

Re: Running Inverters 24 Seven

My Xantrex ps1800 runs continually now that I have an electric fridge.It would not start in power save mode.
My fridge is rated 100 watts in run and 130 watts in auto defrost mode.Not sure how often it goes into defrost But it only uses .9 of kwh per 24 hours.

techntrek · April 2011

Re: Running Inverters 24 Seven

Phil, have you tried disconnecting the defrost heater? You could put it on a switch and turn it on every few weeks when you notice some buildup.

PhilS · April 2011

Re: Running Inverters 24 Seven

techntrek wrote: »

Phil, have you tried disconnecting the defrost heater? You could put it on a switch and turn it on every few weeks when you notice some buildup.

Nope, haven't messed with anything in the fridge controls. I've seen posts that if you do that, the "unseen" ice buildup can be a problem with airflow. But the main reason is that the fridge only uses about 1 KWH per day similar to petertearai's readings. This is not only acceptable, but MUCH improved energy consumption compared to the pair of propane refrigerators that it replaced.

Besides, the problem with "search" means that until the inverter is "on", the fridge isn't actually running. If it went long enough food could get warm. That could happen if we went away for a few days and never turned anything else on that would pull the inverter out of "search". We HAVE left for up to a week and had no problems.

As it is, it doesn't use very much power and requires NO monitoring except for the icemaker, which I turn off when the bin is almost full. And if I don't, it turns itself off when the bin is absolutely full.

Unlike the propane units that required burner orifice cleaning twice a year and defrosting a few times a year.

Phil

BB. · April 2011

Re: Running Inverters 24 Seven

I forget if it was here or somewhere else I read that after about 24 hours with the defrost heaters disabled, the power usage started to go up because of ice blockage on the evaporator(s).

Some refrigerators have heaters around the door edges (anti-sweat)--turning those off will save power (don't know if newer refrigerators/energy star rated have door heaters or not).

If you do experiment with disabling the defrost heaters, do it with a kill-a-watt meter to ensure that you are actually saving power.

-Bill

vcallaway · April 2011

Re: Running Inverters 24 Seven

My cheap ebay Suntech 2k inverter has been on for the last few years. It is standby power for my house. Gets used quite a bit in the winter

machineman · April 2011

Re: Running Inverters 24 Seven

Magnum MS4024 inverter on 24x7 for 1.5yr straight. Lives in a sometimes damp concrete shed. No issues.

silvertop · April 2011

Re: Running Inverters 24 Seven

Thanks guys! I try to manage my loads closer in the winter, being I'm in the Northwest three miles from the Canadian border. I try to get to float daily, Dec.... every five days max. This time of year I can be more free with the AHs. I think I'll eventually just leave the SW 2000 on. Power panel is indoors but it is a hassle to switch and then switch back in the morning . Battery Bank is 880 AH, but I noticed the more power I make the more I use:p This must be a good thing!

2manytoyz · May 2011

Re: Running Inverters 24 Seven

My Xantrex Prosine 1800W inverter has lived in the stand-by mode for the past couple of years. I built some single circuit transfer switches for critical loads, such as my fridges. When the grid goes down, a relay drops out, and the load is transferred to the inverter. When the inverter detects a 20W or higher load, it powers up. When the grid comes back online, the relay engages, transfers the load back to the grid, inverter goes back to sleep.

It draws less that 1.5 Watts in the standby mode. It sends out a pulse every couple of seconds to determine if a load has been applied. If this inverter is left on, it has a parasitic load of 15.96 Watts/hr.

So rather than leave it on, using a significant amount of power while doing nothing, I'm using smaller 400W MSW inverters for lighting. One inverter for outdoor lighting, another for indoor lighting. The one used for outdoor lighting operates from sundown to sun up, every night, for the past few years. Pretty impressive for a $29 inverter. It did have a failure of the cooling fan (operates constantly when inverter on), so I replaced the internal fan.

I eventually had to replace the fan in the other Vector inverter, same issue. No problems with the new fans.

I added a 12V remote control module to remotely turn the inverter on/off as needed. Details about that setup here: http://2manytoyz.com/gridless.html

Here are the measurements I've made regarding inverter idle current: http://2manytoyz.com/noload.html

So even a very cheap inverter can be left on for entended periods. Might have to replace the fan if it isn't thermostatically controlled as it is a wear item. My Prosine inverter only runs the fan as needed.

niel · May 2011

Re: Running Inverters 24 Seven

be careful as to not assume a smaller inverter or an msw inverter will automatically draw less power in standby than bigger sine wave inverters do because this just isn't always so.

Running Inverters 24 Seven

Comments

Categories