We have an old fashioned electric percolater we run off the inverter. It draws abut 75 amps for 3-4 minutes, so not much worse than the hair dryer.
Joel On Wed, Oct 18, 2023 at 9:10 AM Della Barba, Joe via CnC-List < cnc-list@cnc-list.com> wrote: > You can, you just have to think it through. > > My wife can dry her hair, that draws about 50 amps for 5 minutes or so. I > can’t run my cabin heater at 500 or 1000 watts off the battery, it would > run the battery dead before the boat got very warm. Given most of our C&Cs > were designed to be relatively light boats without huge battery banks, we > are mostly a poor fit for trying to use high-draw AC house appliances > running off of batteries. I use an AC vacuum and an AC coffee grinder, but > I don’t try and use an electric coffee pot. Using the stove is far more > efficient as far as turning fuel into hot water. > > What is it you want to run on the boat? > > > > > > *Joe Della Barba* > > Coquina > > > > > > *From:* Richard Bush via CnC-List <cnc-list@cnc-list.com> > *Sent:* Wednesday, October 18, 2023 8:56 AM > *To:* cnc-list@cnc-list.com > *Cc:* Richard Bush <bushma...@aol.com> > *Subject:* [EXTERNAL] Stus-List Re: Sizing an inverter > > > > Paul, If I understand your point, it is that we shouldn't be relying on > battery power for any appliances or coffee pots...etc.; is there any > alternative that doesn't involve solar? thanks! > > > > Richard > > 1985 C&C 37 CB; Ohio River, Mile 584: > > Richard N. Bush Law Offices > > 2950 Breckenridge Lane, Suite Nine > > Louisville, Kentucky 40220 > > (502) 584-7255 > > > > > > On Wednesday, October 18, 2023 at 07:12:19 AM EDT, Dreuge via CnC-List < > cnc-list@cnc-list.com> wrote: > > > > > > Hi Chuck, > > > > First off, 12V * 100 A*hr = 1200 W*hr. But keep in mind that A*hr > battery ratings for a 100 A*hr battery is tested typical at 5 amps(or > 0.05C). That is your 100 A*hr is 5A * 20hr. At this rate the battery is > only providing 12.5V * 5A = 63 Watts. At higher current loads, your > effective battery capacity will be much much less due to Peuket Effect > losses. In fact, a 100 A*hr rated lead-acid battery at 100 amp load would > only provide about 20 A*hr of energy(and lots of heat). To add to the > insult, lead acid based batteries like AGM should not be depleted below > 50% capacity to limit damage, so reserving 1 battery for start leaves only > 50 A*hr for your house bank at loads of about 5 amps. At a 20A load, the > 100 A*hr (50 A*hr effective) only provides 60 A*hr (30 A*hr effective). > That’s about 30 A*hr / 20A = 1.5 hrs of use. > > > > A 1000 W inverter could draw a max of 1000W / 12.5V = 80 Amps (but likely > higher due to a voltage drop). This would drain your battery in 6 - 10 > minutes. > > > > I gave a talk to some local Hams about Solar Off-Grid Systems. I posted > the slides on my blog (see link below). On slides 5 & 6, I discuss > battery discharge capacity and bank sizes. > > > > > > https://svjohannarose.blogspot.com/2021/10/solar-off-grid-system.html > > > > > > On Johanna Rose, I have a 2000W inverter charger. When I run my > microwave, it draws about 100A from a 560 A*hr LiFePO4 battery. Like > Dennis, I have my inverter connected to my panel powering all AC loads > except for my A/C unit and water heater. The inverter has a built in > transfer switch which automatically (and smoothly) transfers to shore power > when available. > > > > - > Paul E. > > 1981 C&C Landfall 38 > S/V Johanna Rose > Fort Walton Beach, FL > > > > http://svjohannarose.blogspot.com/ > > > > On Oct 17, 2023, at 7:27 PM, via CnC-List <cnc-list@cnc-list.com> wrote: > > > > OK, an DC/AC Pure Sine Wave inverter looks attractive > > > > I've heard some boats have 1000 watt, some 2000watt and some 3000 or more. > > What size inverter is right for a boat equipped with two 100Ah AGM > batteries? > > One battery provides 12v x 100ah: 1200watts. My system can provide 2400 > watts but I usually reserve one battery to restart the engine and run on > the other battery. Does the inverter get fed from a bus common to both > batteries, or to the selector switch marked, "Off, 1, both, 2"? > > > > Thanks, > > Chuck S > > > > > > Please show your appreciation for this list and the Photo Album site and > help me pay the associated bills. Make a contribution at: > https://www.paypal.me/stumurray > Thanks for your help. > Stu > Please show your appreciation for this list and the Photo Album site and > help me pay the associated bills. Make a contribution at: > https://www.paypal.me/stumurray > Thanks for your help. > Stu > -- Joel
Please show your appreciation for this list and the Photo Album site and help me pay the associated bills. Make a contribution at: https://www.paypal.me/stumurray Thanks for your help. Stu
