Real World 4 Hour Test of Inverter

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Dataman

Minister of Fire
Sep 10, 2018
1,242
Newport, Wa
Did my 1st real world test of my Backup Inverter today (Sep 24, 64f outside). Stove draws about 102 watts on Medium Speed. 1.02 Amps. Test done to see if this battery is any good and provides power. Inverter will draw it down to Low "battery alarm: 10.5 Vdc-11.0 VDC"

On the Surface it seems I can get my 8 hours. But it's not cold enough to do more than test the battery. Will do another test in November.

Pulled the Gizmo (Spartan Power Meter).

Max Useage: 414w - Stove Light
Amps: 3.828

If it ran this way all the time couple hours run time (switch to manual on battery)

On Low side 122 watts and 1.02 amps on Med Fan Settings.

Took more readings:

High Fan Speed:

1.9A 116w - 4.31 Hours Run Time on 100ah battery

Medium Fan Speed:

.42a 69w - 7.24 Hours Run Time on 100ah battery

Note: This assume no relights and 100 auger/fan running at this speeds. So I expect more.

Numbers say 8 hours run time. (I doubt it, say 4-6 real world cold)

Aims 1250 Watt 12V Pure Sine Wave Inverter Charger
PICOGLF12W12V120AL

Universal UB121000-45978 12v 100AH Deep Cycle AGM Battery 12V 24V 48V(Black)

Harmon XXV Pellet Stove
Started at 11:30am

Voltage: Time:
13.36 Before Start
12.08 11:32am - Cold Auto Start (Max Draw)
12.50 12:08am
12.47 12:30am
12:50 12:45am
12:00 1:47pm - Cold Auto Start (Max Draw)
12:31 2:05pm
12:26 2:44pm
12:20 3:13pm
12.12 3:30pm
 
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How many batteries do you have hooked up to inverter?
 
Thanks. I always like seeing actual numbers. If you do try running the battery down when it gets colder please let us know the results.

There is no auto-cutover is there? Any maintenance required for the battery?
 
Thanks. I always like seeing actual numbers. If you do try running the battery down when it gets colder please let us know the results.

There is no auto-cutover is there? Any maintenance required for the battery?

1 Battery 100AH (2nd one next year). Yes there is auto cutoff at 10.5v. Inverter does maintenance of battery. Float Charge and Such. I will run the same test when it's lots colder to see "real world" results. This test gave me confidence on the battery not being bad (so far).

Last night pretty cold and house toasty. 30f outside. But last week of 70's then cold front again. I see need for small Inverter Genny for Long Term power outage. Have 7k genny for Well and Lights. Doubt I have more than 3 days of Propane. Figure I can run to town for more. Of course when it happen it will be like 2008 and 108" of Snow. We normally get 44" total for Winter.

Going from Wood Stove to Pellet gives up freedom from power outages.
 
Yes. Typical transfer time: 10ms (max)

Pretty nice. Looks like the inverter / controller is around $350, batter $150-ish, so a setup like this would appear to cost at least $500. But if you can get 8 hours out of it... that's pretty good. All of the other UPS I have seen only estimate 10-30 minutes.
 
Pretty nice. Looks like the inverter / controller is around $350, batter $150-ish, so a setup like this would appear to cost at least $500. But if you can get 8 hours out of it... that's pretty good. All of the other UPS I have seen only estimate 10-30 minutes.
UPC won't have 100ah Battery. You can shave some off the price if you go cheaper Inverter. Smaller and Without Charger or Automatic Transfer Switch. But I wanted auto transfer switch and not to have to heave 66lb battery to charge couple times a year. Lazy. AIMS is good product and pure sine wave. Why Harmon recommend ones that you have to change the dip switch is beyond me. I would have to pay for them to come out. At least 75 -100 to drive 40 miles plus labor. Put the money in Pure Sine Wave.
 
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