[dog_house]

If you have a charger in the PD panel think about how you want to handle the inverter and shore power. You don't want the charger being powered by the inverter trying to create a perpetual motion machine. This can be done with a transfer switch or just remembering to turn it off when the inverter is on.

If there is not a charger in it and you select an inverter charger it will take care of this automagically.

If budget allows I would run 2/0 cable and put a 3000w inverter in from the beginning, its a little more money but you are ready for the future and not running it at the max to heat water for 30 minutes at a time.

 

[dog_house]

I re-read you original post and now I'm picking up what you're laying down. The inverter will just power an inverter outlet and the inverter system won't touch the shore power... Disregard my post about a loop between the inverter and charger.

If you are looking for a well built inverter charger I have been using one of these for almost 10 years on a boat to run an air conditioner and it's still kicking. It's a happy medium between super cheap and Instagram Vanlife Victron touchscreen. Xantrex Freedom Hf 1800 Inverter/Charger

You could have it charge the batteries on shore power and it will automate the water heater transfer. Just feed this guy from a breaker in your PD panel and it will charge the batteries on shore power and transfer the water heater from inverter to shore power.

It has been running a 1500w water heater in the boat off AGM batteries for a long time.

 

[dog_house]

Take this as my opinion and nothing more, but I am a fan of directly charging LiFePO4's through a properly set up isolator. Then you can just use a solar controller to be a solar controller. It's simple and efficient. The downside is you will need 2awg wire to hook it up. Isolator or DC to DC don't forget to have a way to shut off all of the chargers when it's below freezing unless your batteries have a reliable low temperature cutoff in the BMS's.

FYI actual testing on our 2022 with the 180a alternator proves there is between a 60 and 120 amp surplus at idle for the charging system when the alternator is hot. With an isolator (direct) system the batteries stop charging when the alternator is fully loaded and can't keep up. The DC to DC chargers pull around 120% of their rated output so this is where the 50a max charger output recommendation comes from when you have the 180a alternator.

 

[dog_house]

I think I want to keep the shore power and solar separate. In other words, shore power comes in, then to a breaker box, then a feed for the roof air, one for the HWH and a couple of outlets. To use the HWH on the inverter, yes I would have to unplug from the 120v outlet and plug into the 2,000 watt inverter....no biggie. Everything else will run off solar/alternator/batteries. I just think it is a little cheaper to go this way and simpler for the smaller van applications.
In the larger Class A's and C we have owned, yes, I agree with having everything switching automatically, since those have a lot more going on with the electrical side. I will check out the Explorist Life...thanks!

 

[dog_house]

Recently rebuilt my first van for my buddy. We eliminated the Pos Bus which literally had two wires attached to it 🙄.

View attachment 94608


In that configuration, I would be tempted to attach a Blue Sea “Dual” terminal fuse (one to panel & one to the inverter)
View attachment 94609


That breaker could be changed to a fuse also. In fact, I would be tempted to have that double fuse holder referenced above & one fuse going to the 12vdc panel sized for the panel/wire & I would place the charge wire from the Kisae & the inverter on the other higher amp fuse.


Another note; That “Smart Shunt” ,,, I believe it is well worth the additional cost to go with the BM712 over the smart shunt. It just does way more, including programmable relays. Not that I use all the “bells & whistles”, but they are there incase of future heeds without replacing the equipment.

Agreed.

If your ON/OFF switch is close to the battery you can put the MRBF fuse holder right on the switch. I’m a huge fan of those and with your setup running at 12v the interrupt capacity is plenty but there will be someone screaming Class T if I suggested it 😝. Use a 200a with 2awg or larger to your inverter and smaller fuse on the other for the DC panel, alternator charge, and Solar charge controller. Size it as large as the weakest link will allow, no bus bars needed.

I reused my own drawing so don’t take the components literally.

 

[dog_house]

Larry, I like the 12ga extension wiring idea...I will go with 10ga to the roof a/c. Much better than stiffy romex.

You only need 12awg for the roof air. 10awg won’t hurt but it’s not needed for any roof air you would put in your van.

When you order the wire watch out for 12/2 vs 12/3. In case you didn’t notice NM (romex) wire doesn’t count the bare ground wire, only the current carrying conductors so for your AC wiring you need 12/3 with a black, white, and green in the same application that would use 12/2 with black, white, and bare copper.

 

[dog_house]

I was going off the diagram, and I didn't realize what looked like a simple battery isolator was a DC/DC converter.

It's an ACR in the diagram, but you can wire a DC/DC in it's place. We direct charge our 1,200ah lithium bank from the alternator as we need all the charging we can get.

The diagram is just to give a visual reference of what the OP was generally talking about, I used the components I already has in Visio.

 

[dog_house]

Thanks for the head up on the wire, I will double check it before plunking down the cash.

The only reason I want to go 10 ga, is sometimes the van will be on a 50+ foot RV cord. Stepping down to a 12awg is most likely ok, but 10awg gives me the warm and fuzzies.

Stand by, I am re-doing the diagram...sharpened crayon in hand.

The only place you need 10ga is from the shore power pedestal to the breaker in the PD panel.

Your shore power will go: 30a receptacle, 10awg tt30 to 30a twist lock extension cord, shore power inlet, 10ga wire to 30a breaker in PD panel. With the loads you have 50' will be fine.

 

[dog_house]

OK, you guys are killing me. The Kisae inverter is model # IC122055. Looking up the specs, ....

IC122055 – Kisae Technology Inc

I see this:
Features include:

• True sinewave output to run motor loads and sensitive electronics without hum or buzz.
• Multi-stage charger to charge your deep-cycle batteries quickly and efficiently to manufacturer’s recommendations.
• Integrated transfer switch to switch seamlessly from shore power to battery power.
• Ideal for running appliances & consumer electronics the way they were designed to be.

Soooo, now I am vacillating on using it to its full potential, or by-passing some neat features.........{sigh}

It actually makes the wiring easier. You can either use it like my original diagram and it will handle your inverter outlets and water heater, or stick it between your shore power and the PD breaker panel 👍.

 

[dog_house]

Here is the Manual;

https://www.kisaepower.com/wp-content/uploads/2015/07/manual_ic121040_ic122055.pdf

View attachment 94637


55 amp charger ,,, but does it have a “Lithium” setting?

Not trying to spend your money @Motor7 ,,, and I’m not sure of the USA price on the Victron Multi 2000VA ,,might be a better choice for you?

https://www.victronenergy.com/upload/documents/Manual-MultiPlus-Compact-2000-120V-REV-09-EN.pdf

View attachment 94638

Those voltages are perfect for LiFePO’s.

 

[dog_house]

Yes, it's common to find completely worn out sloppy loose 30amp campground outlets, while the 120v outlets in the pedestal are like new.

Looks like it has it, bottom of page 11:

https://www.kisaepower.com/wp-content/uploads/2015/07/manual_ic121040_ic122055.pdf

Yup, while this inverter won’t do the magic trick of combining its output with the shore power to let you run big loads off of small power, it does reduce the output of the charger when in pass through to prevent an overload. If you wire it on a branch circuit as you originally planned it would work well on a 20a breaker and manage the current by stopping the charger when the water heater is on.
You could do the same with it on the shore power line between the inlet and AC panel by setting the shore power at 15 amps. When the AC loads in the van got close to 15 amps the charger would turn off allowing you to get by on a 20a outlet.
That looks like a good unit and it’s basically a better version of the Xantrex I posted earlier.

 

[dog_house]

aaaaanddd another Q or 2:

Fuse or Circuit Breaker:
• DC-rated fuse or DC-rated circuit breaker connected along the DC positive line is required.
• For IC122055, select a fuse or circuit breaker with a minimum of 300 Adc

300Adc seems like a lot, I can find fuses in that size, but not in line breakers(which is what I prefer). I see cheap chi-na one's on the 'zon, but nothing from Blue Sea, etc?

• Based on the size of your 12V Battery Bank, determine the overall short circuit current rating of the battery bank from the battery manufacturer. The fuse or circuit breaker chosen has to be able to withstand the short circuit current that may be generated by the battery bank

As for the second part, the battery bank is 200Amp, so would a 200 or a 250amp breaker work for it?

The easiest and safest way to do it is to put a MRBF fuse on each battery so that all of the fuses total 300a (150a on each battery) Use 2/0 wire from the batteries to the inverter. Between the batteries and inverter add an ON/OFF switch and come off that with a third smaller fuse for everything else.
This setup is as good as it gets for safety because there is no wire in the entire system that is not protected and even if a battery fails internally a fuse can open to clear the fault.

The inverter will pull around 200 amps at full output but the fuse is higher to reduce resistance and nuisance trips.

 

[dog_house]

Decisions ,,, Decisions

If I understand @dog_house idea of 2 - 150amps ,,, could work ok. My concern would be depending on the maximum load is that the inverter take it equally from both 150amp fuses. If for “some reason” an unequal amount of amps gets to heat up & blow one of the 150 amp fuses the current now would be drawn from the other battery & 150 amp fuse & that would of course blow if over 150amps.

Short battery bank connectors (your suggestion) & a double fuse ( say a 300 amp & a 60 amp ) could also work. Of course the Blue Sea double fuse holder is rated @ 300 amps & the 300 + 60 is 360 amps ,,, so that would need to be looked at.


as @Motor7 is in the process of designing ,,, a slight change in the wiring can be a big deal ,,, 300 amps is a pretty big deal for me ,,, You know what it is like @GaryBIS ,,, ya gotta get all the performance specs / size of fuses required / etc for all the equipment & review the entire system & figure it out;

Solar Array Volts / Amps
Battery performance specs
DC2DC & MPPT
Inverter / Charger
Shunt
AC Panel
DC Panel

Valid concern, I wish some of the engineers that design things nowadays thought like that!

If you parallel the batteries and connect to opposite ends of the string the "angry pixies" have to travel the same distance on the round trip between the batteries and loads so the two batteries should contribute equally unless one of them fails. I'll draw a diagram tomorrow with the DC system that Motor7 has planned so far and we can go from there. There is plenty of overhead with the 150a fuses on this system, if one blows something went wrong and it needed to.

@Motor7 have you bought your batteries yet or decided on the ones you are going with? So far you have a solid and simple system, the only thing left to figure out is protecting the batteries from being charged when they are below freezing unless I missed something in the discussion. You are actually duplicating the setup we used on our boat to run AC and hot water away from the dock so I can tell you from experience it will definitely work!

 

[dog_house]

Ok, sports fans, Good Morning OK, first off, I did not like the busbars in my diagram, but I did not know the best way to ditch them. Looks like y'all have a good idea of how.

RV8R-

Yes, I forgot all about a shunt. I do not have a stand-alone battery monitor yet, but want to be ready for one. Shunt added.

I have not noticed that the diagram I plagiarized was missing the SP ground wire to Kisae MPPT...fixed.

I also changed ALT to BAT...but I really think they meant "alternator charging circuit".

I don't have the Kisae 1250 in my sweatty mitts, but yes, I will follow the wiring directions that come with it.

A double MRBF mounting bar is a good idea and a step in the direction of eliminating the bar in my diagram.

GaryBis-

I have not unboxed the HWH, but if it has no switch then adding one is a really good idea.

40amp to 60amp change? Is that the one by the positive busbar we want to eliminate?

WayTekwire.com has Eaton Bussmann MRBF's for $10 along with single and double and single mounting bars & covers pretty reasonable, so I think I want to use a few of these in the design.

MaggyMarty-

Thanks for the info on the Kisae DMT1250...mucho helpful!

Dog House-

I have these batteries already :

Now, {nervously joking}....I think I should get my orders in before the house of cards begins to collapse ....or......🥶

I have to add this, you guys have been great, and all of your time and effort to help a "Diagrammatically Challenged" member does not go un-noticed😎

Everything is fine... we are not in a recession... the bond market it fine... it's all fake news...

I say build the van and don't worry about it haha!

You should not need bus bars, I'll whip up a diagram so that everyone can point at it.

Note that display is probably just a volt meter and while very useful for troubleshooting it won't really give you a reliable state of charge since 60% of the time from 0% to 100% is like 0.2v apart.

 

[dog_house]

I think this is where we are so far, let me know if the banks collapse and we need to convert the units to loaves of bread and Promaster parts.

 

[dog_house]

Sorry, right,,,,hold on....

PD5000-AC-DC-Distribution-Panel - Progressive Dynamics

The Mighty Mini Compact All-In-One System offers an AC/DC Power Distribution Panel and Inteli-Power Converter with Charge Wizard battery charging technology.

www.progressivedyn.com

If I am reading it right....dc is also 30a.

I used the same panel and the biggest wire you can get in the DC lug is a 6awg or so. I fed ours with 60a but most RV manufacturers run an unfused THHN wire from the battery right to the lug and they almost never burn to the ground! The manual just kind of points you to the lug and lets you call your own shots.

 

[dog_house]

If you ordered the MRBF holders already you can use a single one on the battery switch and land both the AC/DC panel and the 1250 charger on the same 60a fuse. The combined output of the two is still lower than the max ampacity of the wire feeding the AC/DC panel.

I can tell you from experience that you can land 3 lugs on the shunt. There is a positive wire included in the kit that goes straight to one of the POS battery terminals. The BMV712 draws such a small amount of power it's best to go straight to the battery so that it maintains the state of charge when you turn the battery switch off.

I don't think you need to connect the NEG terminal on the 1250 to the house but it won't hurt. I left it out but if you connect it just make sure it goes to the chassis or shunt, not to the batteries.

 

[dog_house]

Hi,
I think they "only" want a single 300 amp fuse/breaker...

From the manual...
Page 6

Fuse or Circuit Breaker:
• DC-rated fuse or DC-rated circuit breaker connected along the DC positive line is required.
• For IC121040 select a fuse or circuit breaker with a minimum of 150 Adc
• For IC122055, select a fuse or circuit breaker with a minimum of 300 Adc
• Based on the size of your 12V Battery Bank, determine the overall short circuit current rating of
the battery bank from the battery manufacturer. The fuse or circuit breaker chosen has to be
able to withstand the

Assuming that its the right manual.


I think that @dog_house suggested that a good way to do with would be to have a 150 amp MRBF terminal fuse off each battery to add up to 300 amps. I agree, but I think in this case it might be bettesimplier to use a 300 amp direct to inverter (or not ) , and a 2nd smaller fuse to the rest of the DC connections?

I like the double MRBF off one of the battery terminals to make all of the connections without the need for a busbar.

Gary

IMO bussed in parallel the two 150's will act as one 300. I don't like having lithium batteries bussed together without individual protection as they can "gang up" and send thousands of amps into a battery that develops an internal fault. I also drew it the way I did to make the ON/OFF switch install simpler. Otherwise you have more fuses than you really need. Both ways work.

The batteries are rated at 200a continuous each and I would guess that the individual batteries could generate 5k amps or so with a dead short and a failed BMS. The advantage of using the MRBF's (which were designed for large battery banks) this way is you have 10,000 amps of interrupt capacity on each cell and you are not subjecting one single fuse to the total current of the bank. At the end of the day I don' think there is much of a risk with a 12v system when it comes to a fuse failing to open as long as it's a quality part. A huge 24v system and I would want MRBF's minimum, at 48v it's class T all the way. I would normally look to the ABYC for guidance on something like this but I think they are still up in the air on exactly when you need to step up to the big money fuses once you add lithium to the mix. Personally I hope they sign off on the MRBF for lithium, they are my favorite for clean installs.

 

[dog_house]

I like this @dog_house ,,, but for me I am changing a couple of things;

1) 4 position switch in place of the 2 position ,,, Specifically Blue Sea & if @Motor7 is interested I will get the model # for him & perform a wiring diagram. IIRC that switch is good for 600vdc continuous ,,, Unlike @larry barello I like fuses & heavy duty switches ,,, FYI @Motor7 the 4 position switch in the photo below was $5 more than the 2 way & was $67 CAN total ( I think they are $100 CAN now ).

2) the 1 300 amp on top of one of the battery terminals & the battery bank jumpers per your previous notes

I like the design of the fuse holders on the load lug of the 4 position switch that you drew ,,, It is what I use ,,, Recently did a 7 day reno of my 1st van build for my Buddy ,,, See photo below of the fuse holder;

View attachment 94663

I agree on the switch but it makes it slightly more complicated with the upfitter location being used for the chassis tie in. I used a 5511e to let the house jump the van and the van power/jump the house if it's dead or cold. If Motor7 wants that capability it's not a big deal to add it.

I went with a 150a MRBF on each battery for safety but a single 300a like you show above does the same thing, you just lose the protection between the batteries. If one battery shorts internally without protection in the string of batteries the rest of the batteries will dump all of their energy into that fault. Not a big deal with lead acid but when you start putting LiFePO4's in parallel the short circuit current gets out of hand fast.

 

[dog_house]

Ya they seem to be light on details;

https://www.progressivedyn.com/wp-content/uploads/Support/manuals/PD5000-with-converter-Flow.pdf

It says 30 amps ,,, but not the 12vdc panel max current. Then the diagram does not indicate the fuse size;

View attachment 94661



Typical “RV Style” documents ,,, lacking clarity ,,, I will dig a bit deeper.

Regardless if you are good “limiting that 12vdc panel to a max of 30amps I think for your distributed loads from that panel you won’t see anything close to that.

I am a stickler for design docs to be clear & concise ,,, 4 decades of getting Archs & P.Engs to correct their documents gets a bit old ,,, unclear, non-concise, & ambiguous is cheaper to fix before the construction starts;

So 30 Amp is detailed on the 12vdc panel, but I read that for “distribution fuses” ,,, what I want to see is the 12vdc “Max Current Rating” for the “panel”. I may have missed it, but that clear rating I can not see;

View attachment 94662

From the "PD5000 Instalation" manual: There are a pair of lugs on the back of the panel you can connect the POS and NEG wires from the shunt and battery switch. These are rated at a minimum of 80 amps since they offer converters that large to go with the panels. IMO 60 amps is plenty and if you wanted to use one fuse on the battery switch for the 1250 charger and this panel it would be fine. You could also land the 1250 on one of the lugs and run a wire from the other one to the battery switch if that makes the wiring cleaner, it all depends where the components are located in the van. Progressive Dynamics seem like good 'ol boys and not a bunch of engineers over there haha.