Generator questions

[snowman]

I recently purchased a Honda 2000 watt generator as a backup to our solar charging system for longer trips and winter camping. Not sure if I'm being overly cautious with these questions, but having just installed a new solar panel this year and putting 200 amp hours worth of new batteries in last year I really don't want to blow anything up and have to spend more on my electrical!

If I plug the generator into the shore power outlet on the camper does this charge go through the same charge controller as the solar system? (To my knowledge it is the stock charge controller for my 2015 Hawk, looks like this https://www.emarineinc.com/Blue-Sky-Solar-Boost-1524iX-MPPT-Charge-Controller)

If so are the combined input of both the 200w panel and generator likely to overload the controller or system in any way?

I plan to put another panel on top for a total of 375 watts, would this potentially overload the system with the generator added in?

Please excuse my lack of electrical savvy.

Thanks!

 

[Vic Harder]

The shore power connection takes 120V AC in (either from a electrical pole/building or your generator) and then it goes through an AC/DC converter to charge your batteries. The factory uses an iota brand charger. This is completely separate from the Solar charging system.

You mention 200AH of new batteries... AGM(lead acid) or Lithium?

You can use the shore power and solar (and alternator for that matter, but you have to watch out for those really long extension cords while driving ) at the same time, since all three use different controllers to charge the batteries. I've seen 600Watts of charge on my system (330W solar plus 30A DCDC charger) on a sunny day getting both solar and alternator charging while driving...

 

[snowman]

Great to know the shore power system uses a separate charge controller! So it's unlikely I will have issues overloading the controller. I have AGM batteries, do these have issues with charging rate? I want to make sure I'm not pumping too much charge in there and damaging the batteries. (max amps from the panel is 10.5, and the generator is good for 13.5 continuous or 15.5 peak). I assume with the 30 amps DC/DC you're using, plus the solar, its a non issue. I was told FWC installs with fairly small gauge wire from the alternator to the camper and this limits the charge, it sure doesn't seem like i get 30 amps out of mine!

I don't think I will be trying the solar, generator, alternator trifecta any time soon, although I could put the generator on the trailer with the bikes so I would save on ext cords haha!

 

[PaulT]

Easy to get confused with multiple sources of power. The Honda EU2000i provides 2000 watts AC at 120 volts. Cannot add the generator AC amps to the DC amps from your other sources.

The Honda will power the camper's Iota AC-DC converter which can supply 30 amps DC to the camper internal circuitry to run appliances, lights, and charge the camper batteries.

The Honda generator can supply about 8 amps at 12 volts DC if you have Honda's battery charging cable. However, it is not a smart charger and I wouldn't use it unless there were no alternative.

I have both Honda 2000 and Honda 1000 generators and have used either of these to power the camper and charge camper batteries. I no longer have the truck alternator charging my camper. Usually, solar provides all my necessary power. On trips with extended rain, we pick a campground with laundry, showers, and electrical hookups for a night to fully charge the camper batteries and get everything clean as needed.

Have fun and keep learning. I wouldn't want to justify how much I've spent that I wouldn't do again after learning some lessons.

Paul

 

[snowman]

Thanks Paul! I've definitely learned some "lessons" so far haha, hence my caution. So am I correct in saying the iota will take up to 30 amps but the 13.5 continuous amps my generator is putting out in AC will be converted to DC but not necessarily change in quantity?

So wouldn't it still be about 23.5 amps max with the generator plus solar at full capacity?

Also that current the charge controllers will work together well and not blow up my batteries or light my wife and I on fire?

 

[Vic Harder]

So am I correct in saying the iota will take up to 30 amps but the 13.5 continuous amps my generator is putting out in AC will be converted to DC but not necessarily change in quantity?

So wouldn't it still be about 23.5 amps max with the generator plus solar at full capacity?

Also that current the charge controllers will work together well and not blow up my batteries or light my wife and I on fire?

Regarding your first question, the iota will take available power and attempt to put out up to 30A DC, depending on what the batteries need at the time. It can only do this is sufficient power is coming in. So, is your generator sufficient? Short answer = Yes.

Longer answer is that your generator puts out 13.5A at 120V AC. How much power is that? Power = Watts = V *A. 120V * 13.5A = 1620W (close enough to 2000W rating/label?). What does that translate into in terms of DC? Power is still V*A, but now we take 1620W/12V = 135A. More than enough to push out 30A to your batteries!

Solar output is also subject to conversion, that's the beauty of MPPT controllers versus the simpler & older PWM style. If you end up with 375W of solar, your MPPT converts whatever Volts and Amps the panel(s) are putting out and converts that to what the batteries need.

By "need" I mean, if your (AGM) batteries are at 50% or less, they will be around 12.2V resting, and need at least (0.5V more) 12.7 to accept a charge. If they are nearly fully charged at 12.7V, they will need 12.7+.5 = 13.2V to accept a charge.

So, worst case your 375W going into the MPPT has to be converted to 13.2V or so = 375/13.2 = 28A. The maximum that controller you linked to can put out is 20A.

In theory, you could see 20A from the MPPT and 30A from the generator for a total of 50A.

Will this cause a fire? Nope. Most batteries can accept a charge of 0.5C where "C" is equal to the AH of the battery, in your case you mention 200AH of new batteries, or a max charge rate of 100A.

I hope this helps.

 

[snowman]

That is massively helpful, thanks for writing that all out Vic!

Your knowledge spawns more questions of course haha. If my generator after being converted from 120V AC to 12V DC is putting out 135A, and only 30 of those amps are getting past the charge controller, I might as well put the thing in eco mode because a lower output from the generator is almost certainly overshooting what goes through the charge controller? If I can run the thing more quietly and efficiently and it wont change the rate of charging that would be great!

Also, at times the voltage in my system as read from the cigarette lighter outlets on the counter, can reach 14 or 15 volts when my solar panel has full sun. Is this normal or indicative of some failure of my charge controller?

 

[snowman]

Ok upon further investigation it looks like my high voltages are likely just the battery in bulk charging vs float charging at a more reasonable 13.5V!

 

[Vic Harder]

That is massively helpful, thanks for writing that all out Vic!

Your knowledge spawns more questions of course haha. If my generator after being converted from 120V AC to 12V DC is putting out 135A, and only 30 of those amps are getting past the charge controller, I might as well put the thing in eco mode because a lower output from the generator is almost certainly overshooting what goes through the charge controller? If I can run the thing more quietly and efficiently and it wont change the rate of charging that would be great!

Also, at times the voltage in my system as read from the cigarette lighter outlets on the counter, can reach 14 or 15 volts when my solar panel has full sun. Is this normal or indicative of some failure of my charge controller?

Yes to eco mode.

Totally normal. My Victron chargers are all set to 14.4 Bulk, 13.4 float.