Why? What?
Wifey B: Not what? Why? Why the "Why? What?"? Who?
Why? What?
... With the old school A/C units the pumps run/ran anytime the unit was switched on. Even in the fan only position...
There is also another thing to consider...
If you have say 1500 watts of Air Conditioning that runs at for discussion sake a 33% duty cycle on a typical evening you might be actually better off running that on an inverter.
Lets do some math regarding that. 1500 watts is 125 amps at 12v. 125/3=41 amp hours average on your battery bank.
With no other loads applied you could run all night long and not have to run your generator if you had around 800 amp hours of battery.
If you had a higher load or higher duty cycle you could use a State Of Charge meter and tie that to an auto start on your generator. Then when the batteries got low the generator would automatically start up, charge your batteries, then turn itself off.
You could even use a system like that to keep your batteries charged while you were anchor'd off and playing on shore all day, or stuck on a mooring bouy and off the boat for a few days exploring.
""1500 watts is 125 amps at 12v. 125/3=41 amp hours average on your battery bank.
PER HOUR!
41 amps per hour from a battery for 8 hours is 168 amps from a single battery "
Maybe I'm missing something here, terminology mostly. 125/3 = 41 amps, not amp hours. 41 amps for 8 hours is 328 amp hours.
Of course we are not including inverter efficiency.
What am I missing?
Bob
You're not missing anything. The problem was with both terminology and math. What you wrote is correct
Richard
Not true. With the old school A/C units the pumps run/ran anytime the unit was switched on. Even in the fan only position.
Kind of nice to check if you have proper water flow before you turn the compressor on. And very handy when it came time to prime the pump. Plus once the pump was up and running it ran at a constant temperature with no continual starting and stopping duty cycles over and over, hour after hour.
my gen has a magnum energy ags wired directly into the me2000 inverters. It monitors batt. Voltage and is set to come on at 12.4 volts. It also monitors interior temp and starts the gen at a preset temperature. The ac is set to come on at a slightly higher temp. It has a few other bells and whistles that i dont use.
Actually my math is accurate. Terminology is of course open to interpretation.
...
A few weeks ago I was anchored out and left my water heater (1200W) turned on while I was on my inverter. I had used up about 300Ah of battery by the next morning!
Richard
Electric panel can easily be wired so that the chargers/water heater and AC cannot be operated off of the inverter. In my case with AC/DC refrigeration I have also wired the panel so the refrigeration is not run off the inverter.
Basically the inverter feeds a breaker on the panel and the desired AC appliances are fed from that breaker - using their own breakers of course.
I put in a separate breaker panel for just inverter loads. Powers the galley outlets, head outlets (hair driers), TV/entertainment outlets and outlet on the flybridge for keeping the tablet charged.
Bob
"
How goes a typical noisemaker put almost 600AH in a battery bank during the day?
1/10 of 1000AH bank size (C-10 charge rate) would require 100 amps for at least 6 or 7 hours .
Fine if the AC is required all the time there is sunshine .
How are two gen sets electrically isolated?