Community Forums

swprdog · 09-11-2017, 10:39 AM

I have a 2005 40FDQS Alpine Coach. I'm dry camping. Residential Refrigerator. 320watts solar dedicated to house batteries. Brand New 2000 watt Magnum inverter/charger. Brand New Interstate batteries. I hook up to a battery charger at night. (Hookie setup but that's all there is where I'm camped). When I disconnect the external charger in the morning, it reads charged. When I start the generator it goes to 109 amps in the absorb stage then gradually decreases. I think there may be a short to ground but with the batteries indicating charged and the generator amp draw decreasing I can't be sure. Any ideas? I've exhausted my mental capabilities.

Skip426 · 09-11-2017, 10:52 AM

I'm a little confused .

Are you just worried about the readings you're seeing; or is there a particular part of the system not working ?

Inverter not powering fridge properly ?

If you think the way the inverter is reacting to batteries that you believe are fully charged, is wrong ; maybe you should have the batteries tested .
Wouldn't be the first time that a " new " battery was defective .

Dutch Star Don · 09-11-2017, 12:06 PM

"swprdog".....I don't think you have an issue. I think the charger that you're using at night doesn't have the ability to fully charge the batteries in the time frame allowed. I'm guessing it has a gauge or light that says you're fully charged. Remember those type of indicators have ranges. Fully charged could be 90%-100%.

When you start your generator, you're now using a high quality charger with the Magnum and it charges in three stages. If you were really low, it would be starting out at "Bulk" charging instead of "Absorb" charging. After awhile, it will get to "Float" charging where it slows down and charges as needed. On occasion, it can actually get to "Full" charge.

If you were able to leave your auxiliary battery charge on for a longer time without using any coach power, you would probably see your batteries go to full charge.

So........your clip on charger just doesn't have the power to charge overnight, or the ability to actually show what percentage you're batteries are at, just a general charge condition..

rssnape · 09-11-2017, 12:16 PM

I'm confused. If you are dry camping what's powering the battery charger? Why not use the charger on the inverter? You can set the max amperage that the magnum can charge at in the remote. Try lowering it the night before to see if it controls the charge rate.

wolfe10 · 09-12-2017, 09:43 AM

Yup, 109 amp charge rate is certainly in BULK (as it should be).

And, if running the generator to charge the batteries, I would leave the inverter/charger on the MAXIMUM charge rate (power share/power save) set to max unless you have enough other things on that you are in danger of overloading the generator.

The idiot lights indicating level of charge are just that. They are NOT very accurate.

DrDaveMA · 09-12-2017, 12:31 PM

Quote:

Originally Posted by swprdog

I have a 2005 40FDQS Alpine Coach. I'm dry camping. Residential Refrigerator. 320watts solar dedicated to house batteries. Brand New 2000 watt Magnum inverter/charger. Brand New Interstate batteries. I hook up to a battery charger at night. (Hookie setup but that's all there is where I'm camped). When I disconnect the external charger in the morning, it reads charged. When I start the generator it goes to 109 amps in the absorb stage then gradually decreases. I think there may be a short to ground but with the batteries indicating charged and the generator amp draw decreasing I can't be sure. Any ideas? I've exhausted my mental capabilities.

Swprdog, let's get specific, you should have 6 Interstate 6 volt wet cell batteries, that will give you about 775 Amp Capacity in your house battery bank. You should also have 2 twelve volt chassis batteries. Your Vansco system senses the state of charge to the house battery bank and when it is fully charged throws the Trombatta relay to charge the chassis batteries. The "stock" solar option from WRV was 1 or 2 50 watt panels from Shell. If you have a "320 watt system dedicated to the house batteries" you have a solar array from a 3rd party, and they could have changed the way the system works, so you will have to be careful following suggestions here.

Before you start the generator in the morning, with no external power or charger connected, what voltage does your Magnum panel show for the house bank? What voltage does it show when you have the external charger connected? Do you know the external charger is operating properly? Your Magnum has either 3 or 4 stages to it's charging, you should go from "bulk" to "absorb" to "float" and maybe one more I think is "hold" or something like that. That is normal operation for modern multistage inverter/chargers.

Your description does not sound like you have a short to ground, I would suspect maybe mis programming of the Magnum or a faulty external charger. I hope someone more familiar with the 2000 watt Magnum jumps in here.

RVPioneer · 09-12-2017, 03:41 PM

Dry camping with power? Let's call it semi-dry camping. If power is available overnight why not plug in the coach and set it to15A power share, or plug in the refrigerator directly. Unless your up until 2:00am with both TVs on and making microwave popcorn the batteries should not be discharging to a critical level overnight with just a refrigerator cycling on periodically.

As mentioned, an automotive type charger is not capable of properly charging your house battery bank. Have you measured the voltage after running the generator in the morning, at the end of the day after charging from the solar array, in the morning after charging with the external charger, mid-day? Some specific readings could help determine if there actually is a problem.

A properly installed and functioning 320W array is on the small side for extended dry camping with a residential refrigerator. It should be sufficient in a sunny location combined with some frugal consumption habits.

Janet and Todd · 09-12-2017, 09:32 PM

Are you plugging your clamp on battery charger to an outlet on the coach and using the inverter to power your charger to charge your house batteries?

RVPioneer · 09-12-2017, 10:51 PM

Quote:

Originally Posted by Janet and Todd

Are you plugging your clamp on battery charger to an outlet on the coach and using the inverter to power your charger to charge your house batteries?

I can't stop crying at the thought.

Old Scout · 09-13-2017, 03:04 PM

YUP--the OP lost me at hello!

DrDaveMA · 09-20-2017, 08:52 PM

Swprdog, how did things go, did you get the problem resolved?

swprdog · 09-22-2017, 03:22 PM

I have returned home and have access to a real computer so....I was "camping" at the Reno air races. The only external electricity available is a 110 circuit with very low amperage designed solely to charge batteries of RVs connected to it. Every now and then someone tries to use a coffee maker or blow dryer and it pops the main breaker. I have 100 watt solar panels for the starting batteries and an additional 320 watts (four 80 watt panels) with a separate controller wired to the coach batteries. I did not take readings of battery voltage during the times suggested by a responder. I also did not connect my battery charger to 110 in the coach with the generator operating(although the thought did cross my mind). I purchased a fairly good Shumacher digital charger and kept it plugged in at night. Before I purchased the charger the refrigerator would go off about 5am and take out the light above the sink and the night stand lights. All other light circuits worked fine. This would happen until I started the generator and everything would work fine. I think that the night stand lights, the kitchen lights, and the refrigerator are all run by the inverter, which stopped operating when battery voltage became low. I cleaned all battery connections and load tested all batteries. I subsequently replaced all batteries just to be sure they were not the problem. My conclusion is that the residential refrigerator power and the power required by the inverter just to invert is more than my system can handle and that the Alpine Coach was designed to be plugged in every night. It was not designed for extensive "dry" camping. If I am missing something or perhaps need to change settings, please let me know.

Old Scout · 09-22-2017, 04:55 PM

Nope--the 2005 Alpine design was very capable of running the residential frig. all night. "Assume" your rig has the OEM Amana frig and 8 six-volt batteries for the house bank. The Amana is probably not as efficient as newer frigs but turning off the ice maker at night and setting the manual defrost cycle, if so equipped, to run during genset time will help reduce overnight amp draw.

Still a lot of info missing here but this is where I think you are going wrong with your conclusions. 1- normally, you need about 3hours of run time in the mornings to fully charge the battery bank. 2- you then need another 2-3 hours in the evening to recharge the bats. 3- 320 watts of solar helps some but about all it does is run the frig. all day OR partially recover bats but not both. 4- doesn't sound like your 120v bat charger is very large--otherwise wouldn't have run on the minimal shore power you described.

So my conclusions are: A-your 2005 is certainly designed to run the frig over night; B- You didn't mention/include what other amp draws you have on all day or how long you are running your genset each day to recover your bats. C- Pretty clear to me your remote charger was too small to make a big difference in recharging and you didn't run your genset[inverter/charger max 120 DC amps] long enough to fully recharge the bats each night. Also a bit curious to understand why you tested your bats but decided to get new ones anyway?????
PS--you do need to verify that the setting on you inverter/charger match your house battery bank specs.

twinboat · 09-22-2017, 05:25 PM

Think about this. You have over 600 AH of battery capacity.

Sometime during the night, the inverter is shutting down due to low voltage. That means that your batteries are discharged below 50%, or 300AH.

If your inverter/charger is outputting 100 amps, you will need to run the generator at least 4 hours to replace that 300 AH.

A thing to check.

Low battery cutoff. That will be the volts that the inverter shuts down. To high a setting and your not running your batteries down, your just shutting of the inverter early.