O C Diver.
Just so I understand your point, is the "Energy Guide Label" the same label as "refrigerator electric label" that you referenced?
What does the info. on the Energy Guide label (typically Annual Energy Consumption in kWh and Annual Cost, based on $0.12 per kWh) have to do with sizing an inverter to power the refer?
Regardless of your responses, if the refer. has a defrost element (H to T says his Magic one does not) and that element draws 5 Amps at 120 V AC (mine does) would you power it with an inverter that is not capable of producing the 600W of power required to run the defrost element? If so why?
What I don't get is the "No" part.
My DE/EV 0041 happily switches between 12v and 240v. Using 240 whenever it`s there.Jeff.
I don't get it either.
If someone wants to run the refer. only on a dedicated small inverter and experience the losses from battery charging, and inverting whenever the refer. is on, versus running it off of the grid likely 80 percent of the time and off a 3kW inverter the remaining 20 percent of the time, then have at it.
Remember, 20 percent of the time is 1752 hours or 73 days per year.
I would sure like to see the calculations that justify the system design.
..... If you're using a 3,000 watt inverter to generate 250 watts, it may not be as efficient. The point being, if you spend the night at anchor, the smaller inverter might consume significantly less energy that the large one between standby consumption and inefficiency.
Again, standby power draw of the 3000w inverter is 15w. 1.25ah. Overnight, draw is 12ah-15ah draw down. The OP hasn't described the size of his house bank, but 400ah is common, 200ah (two x 12v) is minimum I've seen.
So maybe a 400w inverter is 2x more efficient (....maybe), but does it really may a difference? Rather than add another inverter with cabling, circuit protection, and a selector switch, maybe just add another battery?
Peter
It's all about the Btu's required to melt the ice on the evaporator.
...the smaller inverter has a much lower standby consumption and probably a greater efficiency at the lower wattage.
I also don`t get the wisdom of constantly passing amps in and amps out to power the inverter, especially when perfectly good 120/240 is there. Do batteries like being kept that busy?
The OP hasn't described the size of his house bank...
Our house bank is three 198 amp hour AGMs. They have had a couple episodes of being discharged to 0% on our Balmar Smartgauge. While I have not done any real load testing to document their state or condition, my observation is that the state of charge on the Smartgauge drops far faster than it should.
I am pleased to see that we tend to agree on the approximate duration of the defrost cycle (I said in post 24 "around 5 Min. every 6 Hrs. or so", while you state "Approx. 30 Min. in 24 Hrs. of compressor time") but I question if your Summit Refer. actually tracks compressor run time or is it just time?
A 250 watt inverter produces 2.1 amps continuous at 120 VAC. Thought your refrigerator amperage was going to be higher than that. I was thinking the 500 watt unit was probably the minimum.
Ted
My ac only fridge is labeled 1 amp at 120 volts, so 120 watts. That would be 10 amps on the inverter, plus whatever the inverter losses are. That probably doesn't include start up surge, so double it. I run the whole boat except the AC's and water heater on my 3000 watt inverter/charger which also has 30 amp pass through when shore or gen are available. Works fine for us.
If the manufacturer's label says 1 amp, that should include the startup surge.
Ted
My understanding is that the current draw shown on the label of electric motors typically states Full Load Amps. (FLA)
Older motors used to show the Locked Rotor Amps (LRA) which is your start up surge, but this seems to be replaced with a Code now that you need the key (a list) in order to calculate the suitable value.
As this LRA occurs for only about 150 milliseconds at each start and is 3 to 6 times the FLA, I doubt if it is included in the current draw shown on the motor label.
Before we do any real depending on the batteries, they will be replaced with the best option of the day. Separate issue, of course, but our objective is to spend days at a time on the hook and away from shore power. We keep our fingers crossed that our 9000 watt Kohler remains dependable, but it will almost certainly be supplemented by 1000 watts of solar when the time comes.
Just remember that the inverter has to handle not only the running amps/watts of the fridge but also the in-rush current at the start of the cycle. Good inverters can (which includes Victron). Off-brands, who knows?
You read it correctly. The intention is for a dedicated inverter. Assuming I read it correctly.I thought he was going with a small inverter for just the refer. Maybe I misunderstood???
If the Balmer Smartguage is set up like our LinkPro, when it reads 0% it is at the banks 50% discharge. Check the actual amp hours consumed. If only 300 then you did no harm at all to your bank. If the Balmer is set up differently or not programmed for actual bank size then perhaps.
James