Separation of Solar System from RV Converter ?

kswison
kswison Registered Users Posts: 6 ✭✭

I have a question regarding my RV solar system set up. This has more to do with the separation of charging systems.

My RV is totally OFF-Grid.

I set up my own RV solar system with two (2) 265 watt panels for a max 530 Watt system, appropriate iTracer MPPT solar controller, four Trogan 6 volt batteries wire in series and in parallel for a 12V DC storage system. Bogart TM-2030 monitor. The solar charging system is set up with all its required fuses, hooked right onto the RV battery bank, etc. It all works great. Plan to install one more panel this summer.

I also have a 300W wind turbine mounted on my shed adjacent my shed. It has a directional charge diode on it installed on the line down from the turbine down to the small solar controller that is mounted in the shed. That solar charger is also hooked up to the batteries in the RV. So, if the wind is blowing at night after sunset I am still making/charging power to the RV at night (or day). It works when it windy enough, but we do not have as much wind as I thought we had, so while it is set up correctly, i do not see a lot of power generated from this. Oh well…. but it does provide some power.

It is my understanding that all charging sources should be set on their own charge controller. So, I have done that, separated my solar systems with separate charge controllers. All hooked up to the same RV battery bank. Seems to work well.

We winter camp. When we are out for more than 2 days we need to run the generator at night to keep the furnace going cause I just do not have enough DC storage for that length of stay during the winter. Works great for the rest of the year or just overnight in the winter.

Problem is my RV Converter no longer works when plugged into my generator, as the RV Converter quit shortly after installing the solar system.

Questions:

As the RV’s converter is a charging system should I have installed a charge controller between the RV Converter and the RV’s battery bank. RV Trailer is 10 years old and we use it on average 2 weekends a month, year round, even winter camping. So, the trailer sees a fair bit of use.

As I did not install a charge controller on the RV Converter, is it possible that the charge from the Solar System reached the RV Converter and fried it ? Or is it more likely the RC Converter was just at the end of its life?

I am ordering a new IOTA DLS-55 Converter (that matches the original) and plan to install that upon arrival.

I have been considering a few things with the install of the new RV Converter;

Option 1)

Install the DLS-55 with a charge controller on the DC charging line to the RV battery bank. That way all solar charge controller will work the same way and play fair together. Power will not find its way back to the RV Converter. (if that is an issue ?)

However, I think that might be redundant, as I believe the RV Converter should already have a charge controller built into it, as otherwise, it would continuously charge and eventually overcharge the RV Battery bank. But will the solar charge side damage the RV Converter's charge controller again ?

 Option 2) Install a direction diode on the charging line from the RV Converter to the RV battery bank to protect the RV Converter from the other solar charge controllers. Converter is DLS-55, Volts 13.6V, DC Output: 55 amps

Considering something like this Rectifier Diode, as it will handle up to 100V @ 60 amps 

https://www.ebay.ca/itm/60HF10-International-Rectifier-Diode-Rectifier-100V-60A-NOS-Qty-1/132913814632?hash=item1ef247dc68:g:qLwAAOSwh2xYBpUk:rk:14:pf:0#shpCntId

I am no expert at this. I am uncertain as to if the solar charging system could have damaged the RV Converter. It just seems strange to me that the RV Converter quit within a few months or less after installing the solar system.

Seems to make sense to me to separate and protect the RV Converter from other charging systems.

 Leaning more to Option 2.

 

Thoughts ?  Any help is greatly appreciated. Thanks in advance.


Oh, I have not installed a SHORE POWER A/B switch as the two systems are separate in the RV. The only thing they share is the DC battery bank. I wired the RV with a new completely separate set of orange 110V duplex plugs that run off the inverter. So for power use, it's easy for the family to understand. If the generator is running you can use the white duplex plugs. If not, then turn the Inverter on and plug into the orange plugs. 

So, if I have my generator running through the day charging the batteries, the RC Converter is charging the RV battery bank as well as the solar systems. 

The Breaker Panel of the RV is hooked up to the battery to run all the DC lights from the batteries. At least that is the way I think it is, I will have to check circuits when I install the new Converter, to ensure that the Converter charge line only goes to the battery (with the directional diode in option 2). Then ensure the Break panel is only drawing directly from the RV battery bank. I need to make sure there is no cross wiring in there as that might burn out the RV Converter.


Comments

  • kswison
    kswison Registered Users Posts: 6 ✭✭
    Since this posted I found this...

    Can I run the output of my converter through the solar regulator?

    Not a good idea. In fact, usually a really bad idea. Because many of the converters that come with original equipment are, quite frankly, junk. We get a lot of inquiries about running the output of the converter through the solar charge regulator for better regulation. There are two major problems with that - the first is that the output of the converter is not usually regulated, and is in fact "pulsating" DC with no filtering - it is basically 120 Hz pulsating DC. This drives most controllers nuts trying to figure out how to regulate this constantly changing current and voltage. The second, and more serious, is that most converters are not "current limited" like PV panels are. (This means that if you short a PV panel, it will only put out about 10% more amps than it's rated current this is known as Isc, or short circuit current). Because the converter is not limited, it is quite possible for them to put out more into a discharged battery than the charge controller can handle. You run a real risk of smoking the controller.

    So I will not go down that path. Bad idea !

    So what about the blocking diode idea ?



  • Estragon
    Estragon Registered Users Posts: 4,496 ✭✭✭✭✭
    edited January 2019 #3
    You should not run the output of the charger(converter) into a charge controller, and should not need a diode between the charger and battery.  The charger is designed to charge the battery connected directly.

    Do check AC wiring though, particularly as it relates to ground and neutral wiring (esp. bonding).  It can get complicated with multiple AC sources and possibly non-isolated inverters and chargers.
    Off-grid.  
    Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
    Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
  • kswison
    kswison Registered Users Posts: 6 ✭✭
    Thanks. My A/C shore power and my A/C inverter power supply systems are completely separate. The DC inverted to A/C side all goes to new and separate (installed by me) orange duplex plugs throughout the trailer at strategic locations. While the A/C shore power (generator) side stays with the original breaker panel and original white RV trailer plugs. The only link between the two supply systems in the 12V DC charging line that runs from the RV Converter to the batteries and the 12V wire that runs back from the batteries to the DC side of the RV's breaker/fuse panel to run all the DC lights, etc. in the trailer. So I should be good there.

    I completely separated the two systems, because I knew that if there were a bunch of switches, etc required to move between power sources the wife and kids wouldn't figure it out when I am not there. This way, if the generator is not on, turn ON the Inverter and plug into the orange plugs.... simple. Happy wife happy life !

    Thanks for your comment.