Electrical Mod -- Feedback Requested

[howson]

So I ran into an unanticipated operational issue with my setup--if shore power is lost it is very easy to overload the inverter. (Remember that a 3000W inverter puts out 25amps of 120VAC.) Twice during a recent trip shore power shut down (campground lost power) and the inverter overloaded due to the air conditioners running and the washer and/or dryer running.

Bottom line is I didn't anticipate this problem, so here's my dilemna:

I want...
1) Full capability to use the Victron inverter's augmentation on all the circuits in the trailer when shore power (through the external power connector) is available from a functioning 120V power source. (Worked great twice on a recent trip when connected to 30A sites.)

2) When shore power is lost (unintentionally) I want some circuits to disconnect automatically.

3) When shore power is disconnected intentionally, I want the ability to power circuits that are normally powered down when shore power is lost.

Here's why...
a) When towing, I want the refrigerator powered by the inverter (intentional loss of shore power). The refrigerator will *not* run on propane since I close the propane bottles prior to departure--the reason I installed an inverter in the first place!

b) When stationary, I want the refrigerator to switch automatically to propane when shore power is lost unintentionally (to save battery/inverter power). I open the propane bottles upon arrival, so the refrigerator will do this automatically when ac power is lost.

c) When shore power is lost unintentionally and we're away from the camper, the inverter is an emergency power source for the 13.5K bedroom air conditioner. The ac is set on low, auto and 72 degrees. By doing this my dogs don't end up trapped in a super-hot RV, at least for a couple of hours. (We're never gone more than 4 hours when we have the dogs with us.)

d) When we're at the trailer and shore power is lost unintentionally, I want high-amperage devices immediately turned off to keep our power load under the inverter's maximum output. The DW and I will then manually unplug chargers and anything else to maximize the batteries/inverter run time. (We actually did this last trip when power was lost at night. The inverter kept the bedroom livable until power was restored.)

Here's what I'm contemplating...


Comments, critiques and/or questions are welcome.

-Howard

[cookinwitdiesel]

Just finished reading this entire thread, what a journey! I am in the planning stages of a pretty extensive system for my Solitude and will be referencing this a lot!

I see that you are now done and operational, did you per chance get an opportunity to view the Keep Your Daydream video/blog about adding a similar setup + solar to their 312bhts?
https://www.keepyourdaydream.com/rv-solar/
https://www.youtube.com/watch?v=IMvuJr1TzxE&t=

My system will leverage the generator and factory ATS and then split the 2x 120v legs through 2 separate 3000VA Victron inverters supplying each side of the AC panel separately. I am very comfortable on the AC side of things but want to learn more about the DC side and how to plan/design/build that properly. This has all been extremely helpful!

[howson]

Just finished reading this entire thread, what a journey! I am in the planning stages of a pretty extensive system for my Solitude and will be referencing this a lot!

I see that you are now done and operational, did you per chance get an opportunity to view the Keep Your Daydream video/blog about adding a similar setup + solar to their 312bhts?
https://www.keepyourdaydream.com/rv-solar/
https://www.youtube.com/watch?v=IMvuJr1TzxE&t=

My system will leverage the generator and factory ATS and then split the 2x 120v legs through 2 separate 3000VA Victron inverters supplying each side of the AC panel separately. I am very comfortable on the AC side of things but want to learn more about the DC side and how to plan/design/build that properly. This has all been extremely helpful!

No, I haven't seen Marc's video. I'll have to watch it.

If you have any specific questions as you move through your planning don't hesitate to ask. I'm not an electrician but at this point I know enough about this stuff to be somewhat helpful (I hope).

-Howard

[cookinwitdiesel]

I am still finalizing a BOM and need to put together a diagram of how it will all fit together, once I have that I will share it here if that is alright.

[howson]

I am still finalizing a BOM and need to put together a diagram of how it will all fit together, once I have that I will share it here if that is alright.

You may very well learn lessons and have info to share that is unique to your Solitude and the dual-inverter (I'm jealous!) setup. I suggest starting your own thread and documenting as you go--mistakes and all.

May be obvious, but a clear and concise requirements document (how you expect the setup to function) is critical to ensure your BOM ("Bill of Materials") is complete. Trust me--you only want to do this once!

[cookinwitdiesel]

https://www.mygrandrv.com/forum/show...176#post245176

Give me your feedback!

[howson]

Please note this is NOT a time-tested installation--copy at your own risk! (I will update this thread if there are unintended side affects.)

Due to limitations of the system, please see the next post, too, for the second video.

I finished the relays to avert overloads. To keep this post short, please see the attached PDF and then watch the two videos.


Video showing the wiring (before I closed up all the panels):


Go to the next post...

[howson]

Video showing an actual test showing what happens when shore power is lost:


Any questions--fire away.

-Howard

[Chiefblueman]

Video showing an actual test showing what happens when shore power is lost:


Any questions--fire away.

-Howard

Howard, that is awesome! Great videos. That's not a trailer, it's a science experiment.

[howson]

Howard, that is awesome! Great videos. That's not a trailer, it's a science experiment.

It was fun figuring it out. Really like that it does exactly what I want it to do and when I want it to do it. Time will tell if I have the right components and if my install holds up. Good or bad, I'll report back when I know.