leaving an inverter running

Arashi
Arashi Registered Users Posts: 12
Would it be alright to leave on of these types of inverters running 24hrs a day, 7 days a week?

http://www.donrowe.com/inverters/wagan_5000.html


...or should it only be used for emergency. My load is about 1500 watts/hour

The inverter would be hooked up to an unlimited supply of batteries charged by an infinite supply of pv panels.

Comments

  • dwh
    dwh Solar Expert Posts: 1,341 ✭✭✭
    Re: leaving an inverter running

    Sure, you can leave it running. The only issue is that is has a "parasitic draw" - which means it is using up some juice even when there is no load on it.

    But with unlimited batteries that's a non-issue.
  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: leaving an inverter running

    Wow, Unlimited PV and Unlimited batteries,, can I run a cord from my house?

    LOL

    Most inverters are rated continuous duty, but maybe not at full capacity. I would feel a bit more comfortable running ~80% of capacity 24/7.

    Tony

    Ps I would be a bit concerned with my loads however to make sure that they are happy with MSW wave form however. Also realize that there is probably some significant invert inefficiencies to be concerned about. Most MSW inverters are not known for their efficiency.
  • Arashi
    Arashi Registered Users Posts: 12
    Re: leaving an inverter running

    Thanks! I dont want to burn the cabin up!
  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: leaving an inverter running

    Proper fusing?

    Tony
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: leaving an inverter running

    Never buy a 5000 Watt, 12 Volt inverter: current @ shut-down Voltage of 10.7 under full load = 467 Amps! At its 'surge' rating of 10,000 Watts it would be 934. Outrageous and unmanageable.

    Also, 1500 Watts steady draw is quite a bit for a cabin. I don't hit that unless the water pump and digester pump are on at the same time. Maybe you should start by re-evaluating your loads. Throw out the electric coffee pot and any other electric heating devices. They're bad news for off-grid power.

    Then go look at the inverter choices available through our host NAWS. Particularly: http://store.solar-electric.com/sasiwain1.html Everything they offer is good quality and reasonable prices. It may not be your best choice for buying, but it will definitely give you a sound base reference for looking at all the options.
  • halfcrazy
    halfcrazy Solar Expert Posts: 720 ✭✭✭
    Re: leaving an inverter running

    Agreed if you want a 5000 watt inverter go 48 volts it will make the current and wire size much more manageable. also I assume the 1500 watts is not steady if it is you will need the unlimited PV.
  • john p
    john p Solar Expert Posts: 814 ✭✭✭
    Re: leaving an inverter running

    Do you have a photo of this you can post here..?The inverter would be hooked up to an unlimited supply of batteries charged by an infinite supply of pv panels.


    Icarus I think a MSW at 93 %efficiency is actually good thats beter than 99% of all sine wave inverters, and they draw less current when "idle"
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: leaving an inverter running

    Check the specifications/measure each inverter... MSW vs TSW seems to be less of an "idle current" / efficiency issue now than it used to be. Today it depends on mfg/model numbers more (i.e., the design and manufacturing co$ts involved).

    Also, depending on the loads, TSW's can be much more efficient in power delivered/load efficiency (for example, motors can use upwards of 20% more power on a MSW inverter vs a TSW).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: leaving an inverter running
    john p wrote: »
    Do you have a photo of this you can post here..?The inverter would be hooked up to an unlimited supply of batteries charged by an infinite supply of pv panels.


    Icarus I think a MSW at 93 %efficiency is actually good thats beter than 99% of all sine wave inverters, and they draw less current when "idle"


    I'm certainly no expert, but I have this notion that cheap MSW inverters have pretty poor efficiency curves, especially at lower output ranges.

    Tony
  • GreenerPower
    GreenerPower Solar Expert Posts: 264 ✭✭✭✭✭✭
    Re: leaving an inverter running

    Its manual says it draws <0.3 ADC swiched on, no load, ~90% efficiency.
    Note that this inverter is not UL listed (or any other certifications). In case of a fire, goodluck dealing with the insurance co.
    GP
    (edit to correct the efficiency, it fell into my blind spot)
  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: leaving an inverter running

    Not to cast aspersions on either the OP or his inverter choice, but a quick search reveals that "wagan corp" is a automotive accessories marketer who got it's start making and selling automotive beaded seat covers!

    Looking through their site, it looks like they just re-brand/clone other cheap inverters. Their TSW inverters look like clones of the Xantrex line.

    The question is, if you are serious about building a series system, (and you have unlimited batteries/PV) why would you buy this inverter? There is something (in fact alot!) to be said for buying name brand, reputable field proven hardware, especially if reliability is a must. For example, a cheap MSW for a weekend cabin to power the lights and the radio might be fine, but where we are, if it doesn't work day in/day out, it might be weeks or conceivably a couple of months before we can get replacements depending on the time of year.

    Tony
  • john p
    john p Solar Expert Posts: 814 ✭✭✭
    Re: leaving an inverter running

    question to anyone.. Have you ever seen an inverter burst into flames and then burn the surrounding area?
  • n3qik
    n3qik Solar Expert Posts: 741 ✭✭
    Re: leaving an inverter running
    john p wrote: »
    question to anyone.. Have you ever seen an inverter burst into flames and then burn the surrounding area?

    Yes to bust into flames, no to surrounding area.

    First transfer switch I tried failed. The 120 amp circuit breaker kept the flames/fire to the inverter now paper weight.
  • GreenerPower
    GreenerPower Solar Expert Posts: 264 ✭✭✭✭✭✭
    Re: leaving an inverter running
    john p wrote: »
    question to anyone.. Have you ever seen an inverter burst into flames and then burn the surrounding area?
    Not likely, but the cause of fire, if any, would likely be secondary. I wouldn't trust anything like this i.e. not specifically designed for 24/7 environment running 24/7 unattended. Common failures are the shorted/fused FETs that switch the high DC current from battery if not designed/heat-sinked properly for 24/7 operation. The reliability of the FETs themselves in these cheap inverters are also in question. Of course, with proper fuse protection, these failures can be contained ... or the insurance companies would find reasons not to pay.
    Happen to run across this article where these inverters are commonly used.
    GP
    PS: I would sell a tini % of this ...unlimited supply of batteries charged by an infinite supply of pv panels. to buy a proven inverter with good track record (and still have essentially ...unlimited supply of batteries charged by an infinite supply of pv panels. left to use)
  • john p
    john p Solar Expert Posts: 814 ✭✭✭
    Re: leaving an inverter running

    I wouldn't trust anything like this i.e. not specifically designed for 24/7 environment running 24/7 unattended. Not always easy to have them attended.. I have installed many MSW and Sinewave ones on boats that get left on permanently and sometimes the owners are away and the boats alone (with other boats to keep it company) and have never had a problem.can only ever remember having 3 inverters I installed in all the installations ive done and thats over 2 hundred over the last 8 yrs. one was a 300 w "industrial inverter sinewave" the other 2 were 1 x300w MSW that "just failed" and the other a 800w MSW that kept working but had thermal shutdown problems. Have never had one that caught fire as there really is not much inside one to burn for more than a few seconds. just today asked a few friends that install them and no one has ever seen one "on fire"
    That is why Iwas asking to see others in other countries what there experiences have been
    Really the internal fuses should blow long before a fire could occur as output devices if they going to fail do so in seconds(about when they get to 120decg c about 315 deg f thats far lower than what it needs to get to even burn paper 450deg f
    and inverter cases are always metal and usually alluminium so it should dissapate the heat of a "blown" inverter
  • GreenerPower
    GreenerPower Solar Expert Posts: 264 ✭✭✭✭✭✭
    Re: leaving an inverter running

    Actually I trust the smaller units more than the bigger ones in the 1000-1500W category.
    The commodity FET used (for price) in these smaller units is likely more than what they need for that wattage, not so for the larger units. I had a wagan 600W MSW for 8 years using off and on as battery load test and it is still OK now.
    These inverters have fuse/breaker on the output/load side but few have fuse on the battery DC input side. This is the failure I was talking about - the battery DC+ to DC- path fused internally. Most people just use cheap #4 or #2 battery cable from Wallmart to hook them up, no fuse protection. That's the likely cause of the fire when the DC+ fused to DC-, not because the inverter bursted in flame. That's why the 1000-2000W 12V units are most dangerous. Why in the world one builds a 5000W or 8000W running from 12V ? But people using these are probably more careful in protecting the battery cable because of the potential current drawn.
    In the past 10 years, I've seen a few 1500W MSW (various brands, similar shape) popping/sparking like crackers inside and tripped a 250A DC breaker while under 1000W load.
    Just a precaution, I'm not saying that all these inverters are bad. The one that I pointed out in a post here in the past is a relatively well built unit. What they commented on that site on other cheap MSW inverters are mostly true. Been there, seen that.
    GP