BAC Forum
General Boards => Technical Support => Topic started by: Dan Murphy on April 14, 2016, 05:44:01 PM
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We are parked at home and plugged into 50 amp shore power. When I looked at the Magnum control panel it showed the inverter was on. I turned off the inverter and the residential refer went off and the little LED power light went out. So without the inverter on i have no shore power.
Should not the power light indicator come on when I plug into shore power and what about the inverter? Do I need the inverter on at all when plugged into shore power.
Now on the trip home we dry camped at a couple Wal-marts and I ran the Genny for cooking and TV watching but turned everything off to go to bed.I thought that fully charged batts would run my residential fridge thru the night but my batts went down real fast with the inverter on.
I must have something wrong but don't know where to look. anyone have any thoughts about what I may be doing wrong here?
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Well, not sure what's going on there because in my '99 when the generator is on it supplies power through the inverter and the inverter does show that status but it is off. In other words if I was watching TV with the generator on then turned off the generator the TV would go off at that point because I didn't have the inverter on. Sounds like perhaps your coach is different with its wiring and that the generator doesn't go through the inverter.
I am curious as to how much current the fridge is using given that our Marquis is over in Bend right now at RV Outfitters getting a Samsung residential installed. I was under the impression if the fridge was fully cooled, then it could certainly operate through the night if necessary - at this point I wonder about it. Perhaps others could share their experience concerning how long dry camping can last with a residential fridge.
Mike
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Mike
we have been hooked up to shore power all winter so never really tested the res fridge until the trip home.On the second night out I checked the fridge when I turned everything off around 10 pm and it was 38 degrees so I thought it would stay cool also especially since it was cool outside so I turned the fridge off and went to bed. By 6 am it was at 54 degrees so that idea didn't work very well.
But the night before I turned everything I could think off except the fridge and ran the fridge off the inverter but the AGS kicked on about 4 am because the batts had got down to 12.1 v.
I was hoping I could turn the fridge off and get thru the night but I don't think so.It is going to need power.
With the inverter running and only the fridge on I used all the battery power up pretty quick.e
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First, I am not familiar with a Magnum. That being said, does the Magnum have to be on to allow shore/generator power to pass through to the coach? Also, what type of fridge do you have? My Norcold runs on 110v when shore/generator power is available. Otherwise it runs on propane/12v. And my fridge runs all the time (boondocking and not) unless it's turned off at the fridge, or has lost access to 12v power. Another thought is your heating system (AquaHot, etc.). Is it turned on and drawing power - either 110v or 12v? What about TVs and receivers (TV or radio)?
I have six large golf cart House batteries. They will only barely get us through a night because we leave the fridge on and have the bedroom TV (and receiver) on all night. Most nights the AGS (Auto Generator Start) will activate after 4 am or so.
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Dan,
Your inverter has a pass-through circuit that should pass the 120 volt shore power through the inverter to the coach circuits that are feed from the inverter regardless of whether the inverter is on or not. Have you checked the shore power lead to be sure that there is nothing wrong there like a tripped breaker?
The problem with the batteries running down overnight, either you are running more from the inverter circuit than you know or your house batteries are getting close to their end of life.
So without checking your battery condition, inverter pass-through circuit, shore power circuit, and amperage draw, I can only suggest that you run those test to determine your problem before attempting any corrective actions.
Gerald
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Thanks Gerald. Checked the shore power breaker again and even though the breaker was on there was no power to the secondary box where that breaker is. Found the problem I hope.The AGS started about 6pm today and I got to looking into it deeper.
What I don't understand is how the inverter ran the fridge since we got home at 4pm Mon till 6pm Thurs when the inverter wouldn't run it even thru the night on the trip home.Thats weird!
We think the AGS must have been running and we never heard it.
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The variations you are experiencing seem perplexing. Hopefully you're getting closer to solving the issue(s). If there is a wiring diagram available, perhaps that would help.
Some salient points are mentioned in the link below. Seems like upgrades may be in order to adequately support a residential unit in a (best case) sun supported dry camping configuration:
http://www.gonewiththewynns.com/rv-residential-refrigerator-power
In our '05 Monterey there are a host of power hungry AC circuits that do NOT get fed by inverter supplied AC but work when shore power is furnished or the generator is running - hydro hot AC element, fridge, washing machine, rooftop units, vacuum outlet and the block heater. The only appliance on one of the inverter circuits is the microwave. But it's an older coach and has an AC/Propane fridge so I'm sure many things are different.
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Wow, according to the Wynns (see the link provided in the preceding post) this fridge - which we just had installed but haven't taken delivery of - may not have been the best bet for us. I must have misread postings here claiming that it used less power than the AC circuit of the GAS/AC model we took out. My original hope was that after it reached equilibrium that it would require very low power usage as long as it remained closed. Am I going to be VERY disappointed in this?
Mike
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We just had a residential fridge installed as well and have noticed we need to run the generator more when boondocking. The biggest difference I think is that when boondocking before we had the fridge on propane and cannot do that now. So, we have added a 24\7 draw on the inverter circuit that wasn't there before. I don't believe the power draw is significant but it is 24\7. We have a Magnum 2800 Inverter and a 6 AGM House Bank.
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I did realize we wouldn't have the propane, but that also I've converted all the lights in the coach (except closet lights) to LED. I figured going from 10Watts per halogen light (and 40W per incandescent) that the LEDs of 1 watt (for halogen) and 9 watts (for 40W) would give back more than enough power to run the fridge if we didn't have it open much after dinner. I don't mind running the generator a while before starting off the next morning or running it for a while as we're on our way, but I would NOT want to have to think about running it in the middle of the night. Our house batteries are 220Amphrs so I thought someone said that these fridges run on 3 to 3.5 amps. So if that is continuous isn't that 3.5amphrs which means that if only the fridge was running we'd last for 60-70hrs? I keep telling my wife that I'll probably be killed due to something electrical because I don't understand it. :)
Mike
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To be clear, I believe that if each 6V battery is 220 AH and you have four batteries total wired in series-parallel, then you have 440 AH total with a 50% useable rating of 220 AH.
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On Mike's post, 3.5 amps to run the refrigerator is probably at 120 volts. The same power at 12 volts is 10 times more amps plus some conversion loss. So you are looking at 35-40 amps from the battery. Less than 10 hours should drain the battery.
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In my 06 PT with this huge refrig i've shut down the gen at 10 pm and in the morning the house battery's are around 12.7 or so.
The 3.5 amp draw would not be constant as the frig only pulls any load when the compressor and fans are running, at night as long as your not opening the door mine will only start up a few time.
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Just for clarification Gerald, I don't need to have the inverter on at all if I'm hooked up to shore power? I've been living in my coach full time for just over a year and have had the inverter on all of the time. I hope I haven't screwed it up that way.
MJ
Dan,
Your inverter has a pass-through circuit that should pass the 120 volt shore power through the inverter to the coach circuits that are feed from the inverter regardless of whether the inverter is on or not. Have you checked the shore power lead to be sure that there is nothing wrong there like a tripped breaker?
The problem with the batteries running down overnight, either you are running more from the inverter circuit than you know or your house batteries are getting close to their end of life.
So without checking your battery condition, inverter pass-through circuit, shore power circuit, and amperage draw, I can only suggest that you run those test to determine your problem before attempting any corrective actions.
Gerald
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To be clear, I believe that if each 6V battery is 220 AH and you have four batteries total wired in series-parallel, then you have 440 AH total with a 50% useable rating of 220 AH.
Ok, so Neal, I have 6 of them with every two tied together (series I guess) to form 12V, then those 3 couples are tied together (parallel I guess) to form 12V. Does that mean I have 660Amphrs with an effective use of 330amphrs?
When I get to the coach today to pick it up, I'll see what the amp draw is but I certainly thought at 3.5amps was 3.5amps and not 35 amps. Didn't know there was a difference. I was thinking it would be 35Watts or thereabouts.
Mike
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In my 06 PT with this huge refrig i've shut down the gen at 10 pm and in the morning the house battery's are around 12.7 or so.
The 3.5 amp draw would not be constant as the frig only pulls any load when the compressor and fans are running, at night as long as your not opening the door mine will only start up a few time.
I hope mine will do the same. I also understand that the ice maker can be turned off as well.
Mike
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Mike, What you might want to do is actually test how many amps you frig is sucking down. Need to place a amp probe on the hot line that feeds the frig. With mine I can do this at the breaker panel as the frig has its own breaker and if you remove the cover panel, but be very very careful dealing with live circuits.
Your frig may be pulling more amps for some reason.
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Just for clarification Gerald, I don't need to have the inverter on at all if I'm hooked up to shore power? I've been living in my coach full time for just over a year and have had the inverter on all of the time. I hope I haven't screwed it up that way.
MJ
Dan,
Your inverter has a pass-through circuit that should pass the 120 volt shore power through the inverter to the coach circuits that are feed from the inverter regardless of whether the inverter is on or not. Have you checked the shore power lead to be sure that there is nothing wrong there like a tripped breaker?
The problem with the batteries running down overnight, either you are running more from the inverter circuit than you know or your house batteries are getting close to their end of life.
So without checking your battery condition, inverter pass-through circuit, shore power circuit, and amperage draw, I can only suggest that you run those test to determine your problem before attempting any corrective actions.
Gerald
I had my inverter on for 12 years. I did that so various phone chargers and lights would work when I unplugged from shore power.
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In addition to the amp hour conversion from 120v 3.5amp to 12v 35 amps, you need to take into account the inverter efficiency typically 90% to 95 % . For example at 90% efficiency the draw is approximately 38.9 amps. finally even when everything else is"turned off" there is parasitic load form a variety of sources and that will allcontribute to drawing down your batteries
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Correct calculation, Mike. 3 battery "pairs" @ 220Ah each = 660Ah w/ 50% = 330 Ah. The six-battery set may just give you the current needed to maintain overnight operation. I'll be interested to read your report once you've got some results.
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Correct calculation, Mike. 3 battery "pairs" @ 220Ah each = 660Ah w/ 50% = 330 Ah. The six-battery set may just give you the current needed to maintain overnight operation. I'll be interested to read your report once you've got some results.
We took delivery of our remodeled 1999 Beaver Marquis from RV Outfitters yesterday. I'll be posting a "review" of RV Outfitters on another thread. The new Samsung 18 model was up to temperature and lots of ice had been made so evidently it had been running and had reached equilibrium. I ran the generator on the way home and once home (at about 6:30pm) I turned everything off except the inverter and the fridge. I did switch off the ice maker which would be normal for us to do if we were dry camping. I spent the night with dog in the coach on the street - to protect our investment since we live in SE Portland - and left the outside light on and the light in the "glass cabinet" on. In other words the same as I've done in the past. I did note on the Prosine Control that when the fridge was cycling, the lowest 2 LEDs were switching back and forth (2 amp to 5 amp back to 2amp, etc). That, to me would indicate the fridge was requiring between 2 and 5 amps (if that is indeed the scale units on the Prosine panel). This morning I got up about 5:45am left the coach on the street, fridge is still on so its now 6:41 and the fridge has been cycling on and off all night on inverter power (12 hours or so to this point). This would be an overnight simulation as all parasitic draw (TV/Sound Bar etc were on but in standby mode). Typically in a dry camp situation I do cut all inverter power by turning off the inverter at bed time but obviously that won't happen any more with the fridge now having been replaced.
I'll post later when we return to the coach this morning. I'll note the LEDs on the prosine panel in so far as voltage and also then turn on the CMP and get the actual voltage and let you know my specific experience. If this fridge is drawing 35amps (which I can say I don't believe) and I have only 330amp hours then that's only 9 hours of operation which clearly I've now blown past, so I truly think that its running on 3.5 or 3.8 or whatever that number is. And that's with all due respect to the post saying that on the inverter you multiply by 10. I simply do not agree but as with everything I stand ready to be convinced.
Mike
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In other threads, Marty wrote about converting to a Samsung in their PT. He did all the work himself. They have 4 fresh Costco golf cart batteries. It was not built with room for 6. After the installation of the fridge, he monitored it carefully for battery draw down. I recall his conclusion was that the fridge compressor runs little that he has no issues with dry camping. Nor does it work hard enough to excessively work the alternator when on the road. It may be due to new appliances have to be compliant to low energy use.
It has been about a year since his installation. Call or email Marty if you need more info.
We have a Samsung in the condo that is typical of the ones used in motorhomes. Turning the ice maker off will save on amp consumption. There are several other selection buttons including "E Saver" or "energy saver" that may make a difference.
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Mike,
The 120V AC amp requirement of the frig times 10 is a little low, maybe 12 would be right given there is efficiency loss within the inverter, some of the energy is consumed by heat created by the electronics. That being said that level of power (amps at 12v) is only required during the time the compressor is on, so assume that you run 20 minutes three times a night at 3.5 amps at 120v or one hour total as an example. That would be 12 times 3.5 amps or 42 amps for one hour which is 42 amp hours. While I believe in total you will consume more than that amount with defrost cycles, background electronics of the fridge and coach, you an see that you should have capacity for at least a night and part of a day if managed.
Later Ed
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We passed our dry camping test (basically when we need to overnight in a Walmart Parking Lot) and the fridge passed. After 13 hours I terminated the test and turned the fridge off as we'll be returning to storage mode until end of May. The prosine still showed green led but it was lower than 12.5 (I think that's the first led for 12V) so the next one down was 11.5 (again its not in front of so I am not sure). So I turned on the CMP and the house batteries were at 12.3.
Mike
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MJ,
If you are on shore power, the inverter does not operate even if it is turned on because it goes into standby mode as soon as it senses 120 volt input from either the generator or shore power. The only difference in having the inverter on or off is that it will immediately turn on and start producing 120 volt current if there is a disruption in shore power if in standby mode. So most owners leave the inverter on (standby) when on shore power, but it is just a personal choice. However, you should always leave the converter (battery charging) portion of the inverter on when on shore power to keep your batteries properly charged.
Gerald