I'm seeking an education on generators. First off, I have a new Yamaha 2000IS. It's great, but I do have some questions. I have one battery 85 ah battery, and will eventually get a bigger one. I don't use the A/C.1. What's a general rule of thumb for the time it takes to recharge a battery? I realize it depends on how low the battery is, but lets say the generator is used every day to replinish 30 amps, and then 70 amps. 2. These generators have the economy switch of some sort. Do you agree it's better to not use this switch if the intention is to watch TV and charge the battery?3. In your opinion, is a 1000W generator inadequate for charging a battery? Seems they're perfect for most appliances, but they may not be practical for charging batteries also.4. And finally, maybe it's fairly simple. The 1000W generator produces 7.5-8.3 amps, while the 2000W generator produces 13.3-16.7 amps. If 70 ah are being used in a day, then is it safe to assume that the 1000w generator would have to run for about 9 hrs per day, while the 2000w generator would have to run for about 5 hrs?Thank you for you input..........Note....I'm beginning to realize a good way to do things is a solar panel and a generator. I could probably get by with a 1000w generator and a 100W panel. My problem is battery bank. I can't fit more than two small batteries or one large one. I'll probably get one large one.

1000w will drive about 40 amps into a battery and is fine for one or two charging. 2000w will drive about twice and is better suited for three or more batteries. Use the eco switch for quieter operation. Full power is still available. My rule of thumb is 15 to 20 amps per battery is fine. Some others will push 35+ amps to really hurry up the process. Charging should take 2 to 4 hours to hit 90%. The last 10% can take another 4 to 6 hours and is best completed at home.Post a pic, we will find a way to get you 3+ batteries.

My HTT came with one battery and two 30# propane tanks. I swapped the tanks and battery locations so now I have 2-12v batteries where the tanks were, and one 30# propane tank where the single battery was. The next trailer will get 2 golf cart batteries. And I found only one source for a single 30# tank cover, but at least I found one.I have a Honda 2000i generator and added a stand-alone 55-amp converter in the forward compartment. When on the generator it'll handle the battery charge, fridge, and a few other items easily. For the price difference I opted for the 2000 over the 1000 and I'm glad I did.On point #4 - you're talking 70AH but that's at 12 volts. The generator amp output is at 120 volts. For round numbers 7.5 amps at 120 volts would equate to 75 amps at 12 volts (assuming 100% converter efficiency.) Realistically a 1000 watt generator would run a 50-60 amp converter but not much else. The 2000 watt genny gives you a cushion for more 120vac stuff. Actually the converter load is higher since they run 14.4 volts or so at first then ramp down.

Hi ZZS.Here is a chart:"The chart above shows the amount of time it took a PD9155 (55-amp) converter set to three different output voltages to recharge a 125 AH (Amp Hour) battery after it was fully discharged to 10.5-volts.14.4-VOLTS (Boost Mode) – Returned the battery to 90% of full charge in approximately 3-hours. The battery reached full charge in approximately 11 hours.13.6-VOLTS (Normal Mode) – Required 40-hours to return the battery to 90% of full charge and 78-hours to reach full charge.13.2-VOLTS (Storage Mode) – Required 60-hours to return the battery to 90% of full charge and 100-hours to reach full charge."

If my batteries are down, my 1000 Honda will run my PD 55 amp converter, but not in the highest (14.4) bulk charge mode..Using the charge wizard, I must shift to normal (13.6) mode for several minutes, before I can shift to bulk mode.If I'm using Sat tv while charging, the charge rate is reduced even more.If your converter is 45 amp max, the 1000 is fine, otherwise get a 2000 if...unlike me, you have room to store it.

I believe my converter is 30 amp. It's this:http://www.wfcoelectronics.com/Images/Products/OtherDocs/9-3.pdfI'll have to get that picture of the tounge of my trailer. See if I can create more battery space. Thanks for asking.

Generators and charging RV batteries - Questions/Comments

BBdawg
Explorer
May 28, 2013
I know this is an old thread and I hope some of you brainiacks are still around.

I am a little overwhelmed with the generator/charger technology and would like to get a simple (if one exists)answer to my situation.

I can not change what I have before our trip, so I want to make sure I don't burn my TT down while on our first 5 day boon docking trip.

I have a 2003 27ft TT with a 45 amp Paralax 7300 (7345) converter/charger, which is a single stage charger and NO (T).
I have two 6 volt GC bats in series.
I have a Generac 5500 watt generator.
I have a Shumacker 2,15,110 amp standalone smart/automatic battery charger with "deep cycle" mode

As we are new to boon docking, we will probably not be very "electric wise" with our 12 volt usage in the beginning.

I will have limited time during the day to recharge the battery from my generator.

My question is:

What is the best way to configure and actually hook up what I am dealing with, to get the best and safest result?

Thanks
Randy
BFL13
Explorer II
Aug 15, 2012
I am not sure what you are asking between amps and amp hours, but maybe this will help in whatever it is you want to know:
ZZSPIRAL1
Explorer
Aug 15, 2012
zzspiral1 wrote:
It's not a big trailer..........I have one of these in cherry wood (not white) less the irritating salesman:
http://www.youtube.com/watch?v=zVHnphWvQQQ

It's actually a cool trailer. Has a BBQ too, which makes an excellent rib eye (on the bone). Overall they are built well, but on the downside:

Much of the low paying detail work was jacked up on this trailer. I ended up redoing a lot of it, because the service center where I bought it from is incompetent, to say the least.

Cheap shower hoses that crack at the plastic connections under little pressure. These hoses are quite common. They're bisque color, and don't buy them. The outdoor shower leaked at the connection, and that will flood the inside of this trailer. I found a good hose (white with metal connection), and used a coupler to connect it to a common sprayer with hose for the kitchen sink. It provides a FAR better spray and it's much easier to handle. Plus if it breaks, you can buy one at any hardware store for $8. Oh yeah, their $20 sprayer broke too. The sprayer is also common (threads break).

I had to laugh at the salesman in that video, because he's talking about "jacking up a 3k trailer" by hand. They're stabilizer jacks. At any rate, one failed on the first trip (partially my bad), so they sent me a new one and I took them off of the trailer. A drill is 10x faster and trouble free.

My leg fell through the top step (ha) and it hurt. I made a simple platform for it. It works great and doesn't need to be attached, it just lays there. Great for dogs.

I sold the mattress for $10. It wasn't worth the plastic it came in.

I'd like to figure out a way to build doors onto the storage box under the bed. And build shelves into the two closets around the bed. As the closets sit they're a pain in the arsch and a true waste of space.

You cannot access the fridge (bummer) with the slider is closed. And unless you're skinny (like me), you cannot access the bathroom with the slider closed.

Incidentally, nice set up smkettner "you could charge 50% batteries within an hour"
ZZSPIRAL1
Explorer
Aug 14, 2012
smkettner wrote:
1000w generator needs a smaller 30 to 40 amp converter to operate normal.
1000w probably will not run the microwave and most people need that too.

When my WFCO quit, I specifically replaced my 55a with a 35 amp so I could use a 1000w gen if needed. Although that will extend charging times.

That makes sense. Well, at least I got the right generator (without knowing why), as I have the Yamaha 2000W with inverter. I was considering buying a 1000W generator, because it's lighter and requires less fuel. I guess I'll have to put on my wish list a: 3-stage 35 amp converter / 1000w generator / 100w solar panel and controller / increased battery bank (maybe 240, tops).

Heck, that's "only" another $2300.

It's not a big trailer..........I have one of these in cherry wood (not white) less the irritating salesman:
http://www.youtube.com/watch?v=zVHnphWvQQQ
time2roll
Nomad
Aug 14, 2012
1000w generator needs a smaller 30 to 40 amp converter to operate normal.
1000w probably will not run the microwave and most people need that too.

When my WFCO quit, I specifically replaced my 55a with a 35 amp so I could use a 1000w gen if needed. Although that will extend charging times.
ZZSPIRAL1
Explorer
Aug 14, 2012
smkettner wrote:
Except the 950w converter needs 1360w of apparent power due to the power factor. (950w / 0.7pf)
A 55 amp converter putting out max will overload a 1000w Honda.

Xantrex white paper on power factor

Ah...........Until you wrote that I hadn't factored in the 950 watts required by the converter. I think you've answered my primary question, which is, a 1000W generator isn't the right choice.
time2roll
Nomad
Aug 14, 2012
Except the 950w converter needs 1360w of apparent power due to the power factor. (950w / 0.7pf)
A 55 amp converter putting out max will overload a 1000w Honda.

Xantrex white paper on power factor
ZZSPIRAL1
Explorer
Aug 14, 2012
mena661 wrote:
ZZSPIRAL1 wrote:
Okay, if I understand correctly:

1. The generator doesn't charge a battery. The generator provides power to the converter and the converter charges the batery.

Yes.

2. If we assume the generator provides 7.5 amps of power into the converter, then simple math says the converter will provide 10 times that (75 amps) into the battery. This is because the generator provides 120 volts and the converter converts it to 12 volts.

No, every device has its own specs. They only draw what they need up to their individual maximums. BUT the generator can only provide so much power. :)

3. However, a converter like mine has a maximum output of 55 amps. Supposing some items are being powered, I suppose it's safe to say 40 amps of power are being used to charge the batteries. I don't know why I chose "40" amps, but I can say this is over my head. The converter output is approx. 13.6 - 14.4 Vdc, but I don't know how to make practical use of this figure. I'm missing something here.

Converter specs will say how much they draw on the AC side. That 13.6-14.4V is how much the voltage the converter sends to the batteries. Your converter is a 3 stage unit, bulk, absorb, and float. Typically 14.4V is bulk (that is when max charging occurs) and 13.6 is float.

4. Charge rate depends on the amount the battery(s) is discharged. The more volts in the battery the slower the charge.

Yep.

5. If I understand this correctly, considering I have a 85ah of battery and a converter with a maximum output of 13.6 to 14.4 Vdc, if I'm not using much power when the generator is on (i.e. not using the microwave), then it doesn't matter whether I use a 1000W generator or a 2000W generator, because they both provide more power than the output of the converter.

Converters draw a certain amount of watts so you have to match that with your generator. Also, generator watts are typically max watts NOT continuous watts. Example: Honda 2000W genny puts out 1600W continuous.

The input for the converter is: 105-130 Volts Alternating Current (VAC), 60 Hz (950 watt)

I assume a 1000w generator(900w continuious) would do the trick and a 2000W generator (1600w continuious)is okay?

This stuff is hard.............Ha. I should have paid attention in school

By the way responders, I appreciate your input.
mena661
Explorer
Aug 14, 2012
ZZSPIRAL1 wrote:
Okay, if I understand correctly:

1. The generator doesn't charge a battery. The generator provides power to the converter and the converter charges the batery.

Yes.

2. If we assume the generator provides 7.5 amps of power into the converter, then simple math says the converter will provide 10 times that (75 amps) into the battery. This is because the generator provides 120 volts and the converter converts it to 12 volts.

No, every device has its own specs. They only draw what they need up to their individual maximums. BUT the generator can only provide so much power. :)

3. However, a converter like mine has a maximum output of 55 amps. Supposing some items are being powered, I suppose it's safe to say 40 amps of power are being used to charge the batteries. I don't know why I chose "40" amps, but I can say this is over my head. The converter output is approx. 13.6 - 14.4 Vdc, but I don't know how to make practical use of this figure. I'm missing something here.

Converter specs will say how much they draw on the AC side. That 13.6-14.4V is how much the voltage the converter sends to the batteries. Your converter is a 3 stage unit, bulk, absorb, and float. Typically 14.4V is bulk (that is when max charging occurs) and 13.6 is float.

4. Charge rate depends on the amount the battery(s) is discharged. The more volts in the battery the slower the charge.

Yep.

5. If I understand this correctly, considering I have a 85ah of battery and a converter with a maximum output of 13.6 to 14.4 Vdc, if I'm not using much power when the generator is on (i.e. not using the microwave), then it doesn't matter whether I use a 1000W generator or a 2000W generator, because they both provide more power than the output of the converter.

Converters draw a certain amount of watts so you have to match that with your generator. Also, generator watts are typically max watts NOT continuous watts. Example: Honda 2000W genny puts out 1600W continuous.
time2roll
Nomad
Aug 14, 2012
55a WFCO will probably just stay at 13.6 especialy with a single battery.
Will be a very slow charge after the first 15 minutes.

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