Generator procedure question

[Marmota]

I'm running 2 Yamaha 2000 generators to charge my 2015 international. They ran about 4.5 hours but isn't over 12. I'm wondering if there are tricks I should know - bats in store vs use, should the inverter be on/off? Thanks

[OTRA15]

Welcome to the forum! You can check if the generator's 120 volts is coming into the trailer by plugging in something like a desk lamp, toaster, corded drill, etc. inside. [Into a regular outlet, not an inverter outlet. Inverter should be off.] Also the voltage readout should be more like 13.6 if the generator voltage is reaching the batteries correctly. Ditto for shore power.

The Use/Store switch should be in the Use position I believe. What battery voltage did the readout have before you started charging? Need to know the state of discharge before assessing whether 4 hours is too long. 12 volts is not a particularly healthy reading.

Have you been using the trailer and batteries recently etc.? What is the background for the current situation?

If you turn off the generator and do not connect shore power, then wait an hour, what is the battery voltage readout?

Good luck,

Peter

PS you don't really need to run both 2000 gens just to charge the batteries. Maybe for the AC, if you are doing that also?

[Marmota]

Nothing but the fan is on. The batteries were down to 9 and charged to 11 in 4.5 hours with both running. We tested air earlier and it worked. Dealership sold me the generators when I bought the trailer but glossed over the details. I feel a bit nervous about it and haven't found clear answers. Had only used shore power before but started using bats I the night of the 30th. Died yesterday - charged back to 12.9 I think last night but dropped this morning. Turned fridge off - now it's just fan.

[OTRA15]

Is this a new trailer from that dealer? Sounds like your batteries may be bad, which happens with a lot of new Airstreams unfortunately due to improper storage/charging by the dealer.

It might be helpful if you give a brief history.

9 volts is not a healthy reading but further info. will enable more expert advisors to help out here.

Peter

PS please double check my first reply as it got edited quite a bit as you replied.

[OTRA15]

Originally Posted by Marmota

I'm running 2 Yamaha 2000 generators to charge my 2015 international. They ran about 4.5 hours but isn't over 12. I'm wondering if there are tricks I should know - bats in store vs use, should the inverter be on/off? Thanks

PS -- I would also consider calling the dealer for feedback and warranty issues, if applicable.

Good luck!

Peter

[AnnArborBob]

If your batteries got down to 9 volts they are likely no longer any good. As previously stated, batteries in new Airstreams are often in bad shape due to poor treatment during transportation/storage. It's too bad Airstream cannot find a solution to this issue.

I would first get the current batteries checked and replaced as needed (I would definitely pursue the dealer for a warranty replacement.) In the future, you only need one 2000 watt generator (or even a 1000 watt one) to simply charge the batteries, 2 X 2000 watt chargers is overkill for anything less than running the Air Conditioner. Make sure that the "store/use" switch is set to "use" when charging or the charging will not take place.

If you are going to rely on your batteries for camping "off the grid" I would encourage you to consider replacing the Airstream-provided single stage charger with a multi stage charger. There are many threads about this on the Forum. Rather than repeat the entire litany here, I would encourage you to use the search function and look for "smart charger" "multi stage charger" and the like and you'll find the information you need on this subject.

Good luck and enjoy your new Airstream!

[Marmota]

Thanks for the help. I appreciate the information and advice. I'll keep reading & learning.

[OTRA15]

Originally Posted by Marmota

Thanks for the help. I appreciate the information and advice. I'll keep reading & learning.

Hoping you got this sorted out with the dealer, if needed.

Thanks,

Peter

[GammaDog]

I agree with the other posters on the probable condition of your batteries and the need to replace the original converter with a three stage model (I use a Progressive Dynamics model as do many others on the Forum).

A single 2000 watt generator will charge your batteries. Your converter only draws 700 or 800 watts. You'll have capacity to spare to run other loads such as a TV or 120v fan. Unless you are also running the air conditioning or microwave the second generator is producing current that is not being used.

Your use/store switch can and should remain in the use position.

As a general rule, 12 volt lead acid batteries should not be discharged below 50% of their capacity or permanent damage will be done. That is a typically at a measured voltage of 12.06 volts. A fully charged batty may read up to 13 volts but it is typically considered fully charged at 12.7. It takes one of my 2000 watt Honda's with my Progressive Dynamics converter about two hours to take by two batteries from 12.0 to 12.7 volts.

[Protagonist]

Originally Posted by Marmota

I'm running 2 Yamaha 2000 generators to charge my 2015 international. They ran about 4.5 hours but isn't over 12. I'm wondering if there are tricks I should know - bats in store vs use, should the inverter be on/off? Thanks

Originally Posted by Marmota

Nothing but the fan is on. The batteries were down to 9 and charged to 11 in 4.5 hours with both running. We tested air earlier and it worked. Dealership sold me the generators when I bought the trailer but glossed over the details. I feel a bit nervous about it and haven't found clear answers. Had only used shore power before but started using bats I the night of the 30th. Died yesterday - charged back to 12.9 I think last night but dropped this morning. Turned fridge off - now it's just fan.

Part of the problem might be that the generators are under-loaded. You get the most bang for the buck if the generator is loaded to somewhere between 50% and 75% of its rated capacity. That means with two 2kW generators running, you should have between 2kW and 3kW load on them while charging the batteries. If only running one generator, the load should be between 1kW and 1.5kW. If the generators are just chugging along at idle, you're not getting enough rpms to do the job of efficiently charging the batteries.

It may seem counter-intuitive to run more appliances while the batteries are charging, but the amount of current drawn by the charger is limited by the charger's fuse so running a bigger generator or powering fewer appliances from it will not charge the batteries faster. What matters most is getting the generator's rpms up, because power produced varies according to generator rpms— and the best way to get generator rpms up is to run more appliances from it at the same time, within limit.

As other posters have noted, if the batteries won't hold a charge then no amount of generator run time will help. This is mostly intended as information for future reference, for after you've dealt with your battery woes.

[TG Twinkie]

These are inverters which create 120 volt AC at 60 cycles digitally. Unlike the common construction generator they do not have to run at 3,600 RPM to develop the 60 cycle required by most AC equipment.
Granted the fuel consumption per watt ratio is better when the unit is loaded.
Running 2 generators to charge the batteries is just wasting fuel. IMHO
If the batteries are below 12 volts for any period of time. Chances are they are shot.

[TG Twinkie]

This explains it much better than I can in a few words.

http://www.yamahaef2000is.com/conven...generator.html

[OTRA15]

Thanks TG Twinkie, that article is an excellent summary of the terminology and differing functions of the new inverter/generators vs. the old generators (only). I had always wondered why the new units work OK at such low RPM's if the electrical load is low.

We continue to be very happy with our tri-fuel Yamaha 1000 from US Carburetor. At our recent trip to an oceanfront CG, the generator could not be heard, as the ocean wave action was the prevailing sound, and our 20' extension hoses let us locate the gen behind the trailer away from everyone else.

Nice!

Peter