Generator Charge Time?

2oldman wrote:
We still don't know what you're charging with.

Well, I don't know either ?? My Lance has a generator hookup in the rear cabinet for a propane generator, which I will not install.

It's wired for charging - so, I intended to hook directly into that line. Altho, after reading here, maybe I need a 'battery charger' for better efficiency??

I have a Optima Digital 400, if that does it more efficiently or faster??

I can't tell you what's in the 2008 Lance 845 because it's in storage yard at the moment.

There are several issues that need sorting:
- Are you using the tiny 12v charge on the front of the generator (7-10amps @ 12v) or are you plugging the shore power cord into the generator and letting the on-board charger do the charging (typically 30-50amps @ 12v) or some stand alone charger.
- If the charger is large, can the small generator handle it without overloading? (probably not an issue but possible)
- How big is the battery bank? A 200amp-hr battery bank won't absorb 100amps even if the charger and generator can produce it.
- How close to 100% charge do you want? Up to 80-90%, you can dump relatively high amps into the battery but then it quickly drops off. To reach 100% you will be spending hours at very low amps to finish topping up to 100%.

Add lots of solar and essentially never run the generator again.

We still don't know what you're charging with.

If we were full-time on the road, I add solar in a heartbeat -- but we also lose power at home some of the time, and want the generator to power our fridge and freezer when we lose it.

SO, generator serves dual purpose -- but now that this solar advice has popped up again, and is becoming very efficient and less costly then when we looked at it a few years ago ... might just do a combination. Thanks for all the input -- B & G

I use a portable 40amp charger. Usually, 2 hours a day keeps me going. However, I also have a 100w solar panel and it alone will keep me going under prime conditions.

We boondock almost exclusively and from reading here on the Tech Issues forum, the 2 biggest changes I made were 1) upgrading the converter to a Progressive Dynamics and 2) upgrading the wiring from the converter to the batteries.

The WFCO converter that came OEM wasn't ever going into "boost" mode when charging...so it was a 3-stage converter that only operated in 2 stages. With the PD4260 I can use the charge wizard feature to boost charging from 13.6v to 14.4v. Then by upgrading the #8 wire to the batteries to a #2 wire, I can deliver more amperage with lower voltage drop.

The result is I can run the Honda about 2 hrs a day and recharge to 100%.

If you plan on being off grid and using a generator to charge, make sure you get a good battery monitor that tracks actual amps in/out of the battery. This way you will get a better idea on just how much you are using, your battery condition, and can even monitor the charge rate. I use the Trimetric 2030, but there are other options too.

For true 50% discharge of a 100 A/hr battery, figuring 15 A/hr charge rate to 90% capacity would require 40 A/hr which is 2.67 run time. After about 90%, your charge rate will start to drop.

work2much wrote:
One other suggestion that will greatly reduce your generator time and give your battery a full charge. Solar. You don't need to spend a bunch or have a complicated system. Just 100 or 200 watts will work all day for you when the sun is out. Many have found even with a minimal system that they can all but quit using their generator sans 120v needs like microwave or air conditioning. You can also significantly upgrade your charging profile with a programmable solar charge controller ensuing that your batteries are getting accurate voltage for 100% SOC and equalization charging.

I totally agree. I have a suitcase solar 160W setup. It's really amazing how much that little bit can charge a battery.

I found my converter mostly useless for quick charging.
When I have discharged battery and start the generator, the converter will go into overheat switch off after couple of minutes and stay off for long minutes before it switches back on for couple of minutes.
So roughly 1 hr of running the converter gives me 10 minutes of charging.
Get good charger and go from there.
I have not that new Schumacher charger going up to 25 amp and it will show me voltage as well as % of charge.
Not very precise, but gives you idea where you stand.
One thing to watch with computerized chargers is that they might have automatic desulfation mode, who will take long time to charge.