How to hook up a generator?

[Stewfish]

I'm off grid. Do I need an automatic transfer switch if ao what one did you like? What about an anti reverse zener diode like my combiner box has?

Lets say solar is doing a poor job at charging on a cloudy day, it would be nice for the genny to be able to charge the batteries at the same time and not need me to go plug in the RV converter and turn off the CC.

I just don't want to back feed either device and screw things up again.

Years ago I hooked up a car charge to my RV bc the oem charger took half a day to top off the batteries. That broke the car charger. I was on the IRV2 forum and people said they could be run at the same time. Now I have a really nice progressive dynamics charger/converter (120v-down-to-12v), I don't want to mess up my converter.

My layout:
I have 6 panels going to a 100a epever tracer, then into 4 golfcart batteries 2s2p 12v that run my RV. No inverter. The generator runs all the 120v stuff if I need it. Currently my progressive dynamics is unplugged and the batteries have only been on solar for about a week.

This shows a transfer switch.

Genny would be my grid power if this is what I need:

Here is a auto transfer switch for the AC 120v side, but I dont have an inverter and I want to switch or combine the DC 12v side/batteries:

 

[snoobler]

Unless I'm missing something, you should be able to simply fire up the genny and use the PD converter to charge.

Any number of chargers may be attached to a battery provided they are all suitably programmed for the battery. One should respect that the total current supplied by all sources should not exceed the max recommended charge current from the battery manufacturer.

Some chargers may not be able to interact with others due to design deficiencies. They may lack back flow protection. Converters have this built in. They have the potential to interact with alternator charging, so they're designed such that they won't back flow current from a higher voltage source. It's possible your "car charger" was just a cheap piece of crap.

Again, based on your description of your configuration - essentially a stock RV system with solar charging added - plug in the PD, fire up the genny and charge. Personally, I would leave the PD plugged in all the time, just to ensure you're getting charging any time the generator is on.

Side note: I have a powermax PM4-100 converter attached to a battery bank. It's operating as a fixed voltage power supply @ 12.7V. The battery is frequently charged from an alternate source that is as high as 15V and up to 300A - the PM4 just sits there doing nothing.

 

[Stewfish]

Unless I'm missing something, you should be able to simply fire up the genny and use the PD converter to charge.

Any number of chargers may be attached to a battery provided they are all suitably programmed for the battery. One should respect that the total current supplied by all sources should not exceed the max recommended charge current from the battery manufacturer.

Some chargers may not be able to interact with others due to design deficiencies. They may lack back flow protection. Converters have this built in. They have the potential to interact with alternator charging, so they're designed such that they won't back flow current from a higher voltage source. It's possible your "car charger" was just a cheap piece of crap.

Again, based on your description of your configuration - essentially a stock RV system with solar charging added - plug in the PD, fire up the genny and charge. Personally, I would leave the PD plugged in all the time, just to ensure you're getting charging any time the generator is on.

Side note: I have a powermax PM4-100 converter attached to a battery bank. It's operating as a fixed voltage power supply @ 12.7V. The battery is frequently charged from an alternate source that is as high as 15V and up to 300A - the PM4 just sits there doing nothing.

Well based on the PD faq page it looks like it's okay. And the EP ever diagram shows that's how you're supposed to hook up a generator. It just sucks I lost a $50 charger last time I tried two chargers at once.

PD website FAQs


Epever:

 

[snoobler]

Yes. If it didn't, as soon as the sun went down, the battery's higher voltage would backfeed into it.

Unless you haven't accurately described your system, or you have defective hardware, plug the PD in, fire up the genny and charge right along with solar.

Once your batteries are in the CV/absorption phase of charging, one of the charging sources will likely cut-out and drop to float. Multiple source charging is only beneficial in the bulk phase.

 

[schmism]

Other options
1) For RV applications that have the standard shore power charger/AC distribution box, you can just plug the shore power line from the RV into the generator. (leaving existing solar charging to the house batteries in place)
2) Using server power supplies (see link in my sig) you can create DC power sources to turn the AC into DC. You can then feed this DC power in through your existing SCC and it will charge your batteries. This ensures that your existing systems in place to monitor battery voltage/cuttoffs still work with the AC generator.
3) you can change your inverter to an all-in-one type that allows you to charge the batteries off AC input. (Growatt/MPP) Some other inverters that offer AC charging (grid/generator) do not allow you to use the DC inverter at the same time as the AC->DC "charger". Growatt/mpp do.

 

[snoobler]

Well based on the PD faq page it looks like it's okay. And the EP ever diagram shows that's how you're supposed to hook up a generator. It just sucks I lost a $50 charger last time I tried two chargers at once.

I suspect the issue was the charger itself. Some do not react well to being on the same AC source charging the same battery.

 

[Stewfish]

Other options
1) For RV applications that have the standard shore power charger/AC distribution box, you can just plug the shore power line from the RV into the generator. (leaving existing solar charging to the house batteries in place)
2) Using server power supplies (see link in my sig) you can create DC power sources to turn the AC into DC. You can then feed this DC power in through your existing SCC and it will charge your batteries. This ensures that your existing systems in place to monitor battery voltage/cuttoffs still work with the AC generator.
3) you can change your inverter to an all-in-one type that allows you to charge the batteries off AC input. (Growatt/MPP) Some other inverters that offer AC charging (grid/generator) do not allow you to use the DC inverter at the same time as the AC->DC "charger". Growatt/mpp do.

I have 2 6kw MPPs but those are for our OR property. We don't want an inverter for the RV right now. Running AC in FL requires a generator on the property here so we have a remote for starting it. It works easy with a 35 gallon gas tank expansion cap. Its for the microwave, and battery powered projector, or laptops when the AC is running and we are home. Its about a gallon a day. $2.50/10 hrs to run it. Everything else is 12v. Most of the time we just need 12v lights and power for the fridge LCD.

FYI your signature links to home pages of stuff. I was not able to dig through and find what you were talking about on another question I had. Also your signature doesn't show up on this forum - see pics. There is nothing about server power supplies in your 6 point/ links on your signature. To get to that page I had to click your name, then again on the next page, then select the about section. Maybe its different on a desktop view vs on a phone.

If moderators could post sticky pages then a lot of common noob questions could easily be answered.

 

[snoobler]

Turn your phone sideways to see signatures.

 

[Stewfish]

Turn your phone sideways to see signatures.

Hu, cool. Didn't know that.

Maybe add some more detail to your signature if possible. Not sure which link would get me to that section.

Anyway, my progressive dynamics RV converter FAQ page says solar is okay, and the epever diagram shows a generator straight to the battery so all should be okay.

Thanks for the help.

 

[snoobler]

I'm not sure what you're asking me to do. I consider my signature a little bloated, so I can't decide if you're being sarcastic.

 

[Stewfish]

I'm not sure what you're asking me to do. I consider my signature a little bloated, so I can't decide if you're being sarcastic.

No, I just couldn't find the sever power supply link. Maybe in wiring? I looked a few and nothing popped out at me.

Here is an example of a sticky even with a table of contents. It has summary descriptions under each section and links to products or threads about that section.

A Newbie's Guide To 4th Gen Cummins - Thread Summaries Knowledge Base

A couple notes on this thread: Most of this info is copy/pasted and not my opinions, but rather that of many people summarized after reading sometimes hundreds of pages on a subject. I did, however, make up some of the analogies and simplified examples that I used to explain things like...

www.igotacummins.com

It would be cool to have this for solar. Not that you need that in your sig. But it would be a easy link to tell people about. I could build it, but after awhile this forum doesn't let you edit your OP so then as new info came along I wouldn't be able to add it to the table if contents

 

[snoobler]

Ah. You're probably right. I've typed it a dozen times.

 

[snoobler]

Charging from multiple sources

One can have as many independent charging sources running concurrently as they like provided they are programmed properly for the voltage of one's battery bank. Examples (some or all at once, even multiples of a single type, different brands, etc.): Solar PV via MPPT Solar PV via PWM AC-DC...

diysolarforum.com

 

[dmitrimedina]

Use an all in one charger controller and inverter it’s so much easy

 

[Stewfish]

Ah. You're probably right. I've typed it a dozen times.

A friend asked me if I could give him info on how to do cabin solar the other day. Its pretty daunting and requires tons on links. After the posts this morning I thought I'll just make a write up. Here is a summary thread I made a first draft of today. I guess since you can't edit a thread OP down the road. I could always link the doc and then update the doc as I get more info. I added your links, and there is tons more that could be added. Let me know what I can add to it, if you think of anything.

Solar Links

docs.google.com