Van build - setup design check?

[HarryN]

You can dig deeper into the inverter standby consumption, but basically every inverter will use some power when turned on, running a load or not.

30 ish watts is in the right general range for this standby power draw, and if you are using wireless monitoring, that uses some as well. It might be 20 - 40 watts, depending on the exact inverter but that is the right general range to run your power system in standby.

@12vDC s suggestion can be a useful approach - as long as you find an inverter with very lower standby power consumption. Smaller does not always mean lower standby power - but it can.

 

[12vDC]

Interesting its actually a good idea maybe to have 2 inverter. One more powerful for the big loads when cooking and a smallish one who idle really low to run the fridge ! Some inverter seems to be idling at like 10w. I would be able to reduce the power consumption a lot maybeeee?

I'm not sure whats the victron BMS limiter is doing ?? how do you compensate anything with it?

Xantrex claims 36W at idle for my model 3000.

I was mistaken, the small inverter I am using is a 300W unit (not 350). I did A LOT of research and chose this Bestek model.

Amazon.com

Many choices out there, find one that will make you happy.

Bestek claims:
The current consumption is 0.005 A in the closed state and 0.3 A in the open state.

The Victron BMS module is a current limiter for alternator charging. It is a safe(r) method of connecting starter and house batteries together for charging.

If and when the house battery bank is depleted and you attempt to recharge directly from the alternator, the house bank will ask for all the power the alternator can provide, there will be a lot of current flowing through your wires and to your components which can be dangerous. The alternator is also exposed to risk where lack of adequate cooling will damage the unit.

(This module is not required. Many examples of direct battery bank alternator charging. I choose not to assume the risk.)

For any situation where I am unable to recharge via solar and/or expending more power than is being generated, I can compensate by idling the engine and charging from the alternator. The risk factor is mitigated by the module.

 

[HarryN]

Xantrex claims 36W at idle for my model 3000.

I was mistaken, the small inverter I am using is a 300W unit (not 350). I did A LOT of research and chose this Bestek model.

Amazon.com

Many choices out there, find one that will make you happy.

Bestek claims:
The current consumption is 0.005 A in the closed state and 0.3 A in the open state.

The Victron BMS module is a current limiter for alternator charging. It is a safe(r) method of connecting starter and house batteries together for charging.

If and when the house battery bank is depleted and you attempt to recharge directly from the alternator, the house bank will ask for all the power the alternator can provide, there will be a lot of current flowing through your wires and to your components which can be dangerous. The alternator is also exposed to risk where lack of adequate cooling will damage the unit.

(This module is not required. Many examples of direct battery bank alternator charging. I choose not to assume the risk.)

For any situation where I am unable to recharge via solar and/or expending more power than is being generated, I can compensate by idling the engine and charging from the alternator. The risk factor is mitigated by the module.

Thanks for the link to that inverter. I have never attempted to run a home refrigerator from anything smaller than a 1 kW PSW inverter.

The funny thing is that my 1 kW inverter has a higher standby power draw than the 2 kW one - same brand.

I need to send them a note as ask if they can improve it.

 

[Reed Cole]

My 1200w Giandel inverter has a 5 watt idle draw. Been reliable for about 4 years now. Mostly with low draw but occasional power tool use.

 

[atelierminceur]

Xantrex claims 36W at idle for my model 3000.

I was mistaken, the small inverter I am using is a 300W unit (not 350). I did A LOT of research and chose this Bestek model.

Amazon.com

Many choices out there, find one that will make you happy.

Bestek claims:
The current consumption is 0.005 A in the closed state and 0.3 A in the open state.

The Victron BMS module is a current limiter for alternator charging. It is a safe(r) method of connecting starter and house batteries together for charging.

If and when the house battery bank is depleted and you attempt to recharge directly from the alternator, the house bank will ask for all the power the alternator can provide, there will be a lot of current flowing through your wires and to your components which can be dangerous. The alternator is also exposed to risk where lack of adequate cooling will damage the unit.

(This module is not required. Many examples of direct battery bank alternator charging. I choose not to assume the risk.)

For any situation where I am unable to recharge via solar and/or expending more power than is being generated, I can compensate by idling the engine and charging from the alternator. The risk factor is mitigated by the module.

Thanks for the infos.
38w idling is still kinda huge compared to the low wattage of the victron stuff, but then price is wayy different wtf.
I think i'm gonna get a good alternator but set myself for 2x 300ah batteries at 12v so i have 600ah that i can refill with shore/ev charging, alternator and lightish 350w solar.
I mean there isnt a way to overcome the consumption as well as with bigger batteries.. and 600Ah for my setup is kinda big

 

[RV8R]

Thanks for the infos.
38w idling is still kinda huge compared to the low wattage of the victron stuff, but then price is wayy different wtf.
I think i'm gonna get a good alternator but set myself for 2x 300ah batteries at 12v so i have 600ah that i can refill with shore/ev charging, alternator and lightish 350w solar.
I mean there isnt a way to overcome the consumption as well as with bigger batteries.. and 600Ah for my setup is kinda big

I’m late to the party here @atelierminceur

I have built 2 Ram Promaster Camper Vans. Design / Building Vans is just a very long list of compromises ( If you don’t get that now, you will when you are done ) .

An energy audit, or “Loads Calculations Spreadsheet” is the first thing you should do. Electrical design starts at the loads & work’s itself back. Also when I say loads I am referring to you planned now loads & your possible future loads ,,, van electrical systems trend to grow in size rather than shrink. Then for your van’s electrical system it will be blaa, blaa, blaa, blaa & “How Are You Going to Charge Your Batteries”? It always comes down to that ,,, always.

“All Things Heat” well and Air Conditioning; How are you going to deal with “All Things Heat”? In North America we have a standard 20lb propane tank ( barbecue size ). 1 20 lb tank holds the same energy as 116 - 100Ahr Lithium Batteries.

My vans have 120vac ( never use it ) & 12vdc 300Ahr AGMs . We have a Propex HS2800 furnace. The fridge is a 12vdc & 120vac Truck Fridge “TF130”.

There is your “Theory” & “Actual” ,,, They are different. You can design for your “Theory”, but I recommend planning for possible expansion ,,, space, wire capacity, easily altered design. More on that if you wish, but it is best to not paint yourself into a corner.

Here is a link to my latest van;

RV8Rs New Build - TETRIS

www.promasterforum.com

So my way of dealing with energy management ( what electrical is really ), is;

1. Conservation ( This is the Biggest thing one can do for long term boondocking )
2. Propane ( 2 -20 lb tanks = 232 100Ahr Lithium Batteries )

My biggest electrical loads are both 12vdc; Fridge & Propane Furnace ( blower ). BTW both actually “heat” the interior of the “well insulated” van . In the summertime of course the furnace is off & we have to attempt to dissipate the heat frm the fridge coil.

So ,,, So much of your van design is going to depend ,,, season, weather, location, etc.



On another note; The most expensive coffee ️ I have ever purchased was @ Starbucks in Bern ,,, So I feel ya on the electrical equipment costs if that was any indication.


Bern ,,, Expensive Coffee, Rose Garden, & This ;

 

[RV8R]

Here is a link to my Kisae 1250;

RV8Rs New Build - TETRIS

www.promasterforum.com

Kisae now makes a 100amp unit ,,, it is new so if you are interested & can’t find it let me know.

Also I believe they have a 12vdc to 24vdc if you ever decided to “series” your 12vdc batteries.


If you are not familiar with the Kisae 1250 it is an Alternator Charger & also a Solar Charger. I do not have solar on my van, & use it purely as a DC2DC charger.

 

[HarryN]

Thanks for the infos.
38w idling is still kinda huge compared to the low wattage of the victron stuff, but then price is wayy different wtf.
I think i'm gonna get a good alternator but set myself for 2x 300ah batteries at 12v so i have 600ah that i can refill with shore/ev charging, alternator and lightish 350w solar.
I mean there isnt a way to overcome the consumption as well as with bigger batteries.. and 600Ah for my setup is kinda big

The Xantrex is a true 3000 watt inverter and will drive inductive loads all day under tough conditions.

The Victron is nominal 3000 va (not watts ) and in mixed resistive / inductive loads, came out to the same 2400 watt capability as the 2 000 watt US made inverter that I use. Also the same as a honda 3000 generator that I rented to do some testing.

 

[atelierminceur]

The Xantrex is a true 3000 watt inverter and will drive inductive loads all day under tough conditions.

The Victron is nominal 3000 va (not watts ) and in mixed resistive / inductive loads, came out to the same 2400 watt capability as the 2 000 watt US made inverter that I use. Also the same as a honda 3000 generator that I rented to do some testing.

oh so the multiplus 3000 isnt outputing 3000w ? okkkk

 

[RV8R]

oh so the multiplus 3000 isnt outputing 3000w ? okkkk

Correct

You can also see the “Zero load power” consumed is 13W

It has a search mode of 3W, but it starts getting tricky for fridges ,,, they need to have a mechanical thermostat not “electrical” digital.

You will also see the rating is @ 25C temperature & things change as the temperature changes.

You will also see the word “Maximum” before “Efficiency” ,,, Don’t expect the “Max”. I would assume 85% .

 

[HarryN]

Correct

You can also see the “Zero load power” consumed is 13W

It has a search mode of 3W, but it starts getting tricky for fridges ,,, they need to have a mechanical thermostat not “electrical” digital.

You will also see the rating is @ 25C temperature & things change as the temperature changes.

You will also see the word “Maximum” before “Efficiency” ,,, Don’t expect the “Max”. I would assume 85% .

View attachment 194883

That is a really interesting page from the manual. The funny thing is that I only used that inverter for a project due to a request and it really did kick off right at 2400 watts. Didn't look at that page before hand. It was a 3000 / 48 but same result.

I was really surprised that all three were essentially identical.

 

[atelierminceur]

You can also see the “Zero load power” consumed is 13W

It has a search mode of 3W, but it starts getting tricky for fridges ,,, they need to have a mechanical thermostat not “electrical” digital.

Oh so basically it will always be at 13w minimum ?
Does it make sense to get a really good like 1200w inverter with 13w idle and run a second 3000w cheapish one with higher consumption mostly when cooking on induction?
The fridge on a 13w one wouldnt be that big of a consuption ?
The victron phoenix is at 8w zero load consumption. Like 1/4 of most inverter i've seen around. It would be minimal to have it run permanently

 

[RV8R]

Oh so basically it will always be at 13w minimum ?
Does it make sense to get a really good like 1200w inverter with 13w idle and run a second 3000w cheapish one with higher consumption mostly when cooking on induction?
The fridge on a 13w one wouldnt be that big of a consuption ?
The victron phoenix is at 8w zero load consumption. Like 1/4 of most inverter i've seen around. It would be minimal to have it run permanently

Correct standby 13W minimum, but down to 3W on search mode & the specs on “The Phoenix” are what they are.

Contact @Tomthumb62 if you are interested in what he went thru to get a fridge to work on search mode ,,, & I will try to find a thread here where @sunshine_eggo had a funny post talking about reality & Bottom line;

“There is No Free Lunch”

&

“ Your Mileage May Vary “

As eggo put it ,,, horrendous, expectations ,,, or something like that ,,, referring to theory & reality


Edit; Hahahaha ,,, I was close but no cigar;




If you want to know more on this topic, I suggest you read this thread about inverters;

Post in thread 'Little help choosing mppt'
https://diysolarforum.com/threads/little-help-choosing-mppt.66214/post-834260



So You have to ponder these “special modes” & how putting them into your design will work out. If the automation & hassle of setup & the restricting parameters are “worth it to you” in order to eek out some battery energy savings.


In Van Building for Me; Simpler & Less is a way way better design philosophy then complicated & more.


That design philosophy sometimes costs me more money, like an expensive but extremely efficient 12vdc fridge.



One more comment for you @atelierminceur ,,, Having gone thru “The Van Building” project a couple of times, I have been where you are on the quest for knowledge. It can sometimes feel a little daunting & very expansive, but you are expanding your knowledge base at a parabolic rate as a newbie & the great thing is once you learn & experience it “you have acquired that knowledge” ,,, It Gets Way Easier .

 

[atelierminceur]

In Van Building for Me; Simpler & Less is a way way better design philosophy then complicated & more.

Yeah i think i'm just gonna go with 12v 2x 300ah battery for 600ah and be done with the idea of two inverters etc.
Just a good one and i don't care about battery anymore that much.. Its less hassle in the end as you say. I mean i'm spending too much time looking for specifics and id rather do something else in the end that spend tens of hours watching inverts review. modulating the setup etc..

 

[MattiFin]

Back when I was building van electrical systems for people, I would always go with at least 4 x 100 amp-hr batteries as a minimum for a project like yours. I still think that you are cutting it too close.

The only reason that I have the smaller system in my explorer is that it is a small vehicle. I took out one of the second row seats to put it there, vs in my mini van that I had, it had 4 batteries and a 2 kW inverter.

It might be possible to replace the alternator in that Transit with the heavy duty version, which is ~ 220 amp range and it generates more power at low rpms. Then you could in theory push it closer to 100 amps.

I feel like lots of people commenting in here are thinking of bigger rigs. Ram Promaster is huge behemoth compared to OP's Transit Connect. Enough space to park the Transit Connect inside the Promaster

Reality is probably that you are not doing that much cooking in a tiny van like that. Or anything else for that matter. There is no space to stand for starters. You get dry(ish) place to lay down, pot of coffee, noodles and maybe a cold beer and thats about it.

Boiling 2x1L of water per day on induction hob =0,24kWh
Keeping pot of potatoes on simmer for 1/2 hour = 0,1kWh (insulated with towel thrown over the pot)
Inverter idle losses = 0,3kWh (possibly 50% of that if fridge works in "search" mode)
Small fridge from european lineup =0,25kWh
+ lights, ventilation and entertainment 0,25kWh
= total 1kWh per day or about 100Ah from 12v system with some losses.

 

[RV8R]

I feel like lots of people commenting in here are thinking of bigger rigs. Ram Promaster is huge behemoth compared to OP's Transit Connect. Enough space to park the Transit Connect inside the Promaster

Reality is probably that you are not doing that much cooking in a tiny van like that. Or anything else for that matter. There is no space to stand for starters. You get dry(ish) place to lay down, pot of coffee, noodles and maybe a cold beer and thats about it.

Boiling 2x1L of water per day on induction hob =0,24kWh
Keeping pot of potatoes on simmer for 1/2 hour = 0,1kWh (insulated with towel thrown over the pot)
Inverter idle losses = 0,3kWh (possibly 50% of that if fridge works in "search" mode)
Small fridge from european lineup =0,25kWh
+ lights, ventilation and entertainment 0,25kWh
= total 1kWh per day or about 100Ah from 12v system with some losses.

That puts into perspective for me .

 

[12vDC]

I feel like lots of people commenting in here are thinking of bigger rigs. Ram Promaster is huge behemoth compared to OP's Transit Connect.

wait whut?

yeah i thought we were talking about a “van”… i probably missed the purpose of this sizeable equipment too. i’m audi5000

 

[atelierminceur]

I feel like lots of people commenting in here are thinking of bigger rigs. Ram Promaster is huge behemoth compared to OP's Transit Connect. Enough space to park the Transit Connect inside the Promaster

Reality is probably that you are not doing that much cooking in a tiny van like that. Or anything else for that matter. There is no space to stand for starters. You get dry(ish) place to lay down, pot of coffee, noodles and maybe a cold beer and thats about it.

Boiling 2x1L of water per day on induction hob =0,24kWh
Keeping pot of potatoes on simmer for 1/2 hour = 0,1kWh (insulated with towel thrown over the pot)
Inverter idle losses = 0,3kWh (possibly 50% of that if fridge works in "search" mode)
Small fridge from european lineup =0,25kWh
+ lights, ventilation and entertainment 0,25kWh
= total 1kWh per day or about 100Ah from 12v system with some losses.

I'm not gonna stand cook but im gonna cook sitting like tons of people do on their WV T vans sitting down. Also i plan of being able to use the cable outside with a mount basically so i can do everything in front of the van!

I mean for sure it's way smaller than most ppl imagine but it still works electricity wise. I need to power the things and somehow be able to do the few things in this small space.. This isnt a van i will want to stay inside for a few days at all with no possibility of standing. Its a van to go hiking, swimming and do sports. If its plan to rain i'm most likely not gonna use it much..

i think i'm more or less fine at 100Ah per day as you say. My maths run me there exactly so

 

[atelierminceur]

wait whut?

yeah i thought we were talking about a “van”… i probably missed the purpose of this sizeable equipment too. i’m audi5000

haha the ford transit custom isnt huge but i've seen livable one online and irl. And so far my design look like its working out, at least in 3D.
Huge vans are just really impractical for what i need. I'd rather park everywhere and it's mostly to stay inside awake a few hours a day. 4-5h or so usually maxx

 

[RV8R]

haha the ford transit custom isnt huge but i've seen livable one online and irl. And so far my design look like its working out, at least in 3D.
Huge vans are just really impractical for what i need. I'd rather park everywhere and it's mostly to stay inside awake a few hours a day. 4-5h or so usually maxx

In “light” of the size of your van, IMO the electrical schematic you posted is HUGE.

If this is your 1st DIY Van, I recommend a holistic approach to imagine your intended use & your actual use ,,, there will be differences.

Haven been thru many many DIYer Projects, there is a transition that happens ( to me at least ), where in the case of a Van while designing & building it is all about the Van. The phenomenon that happens is once using the Van there is a transformation where it becomes all about the Adventure & the Van, the Design, the Build fades into the background.

You have even a smaller finite space than my Vans, & that points me into a design philosophy of less is more & simpler is better.

Now You & I live in different parts of the World, so there will be many differences, so there is that.

Consider “All Things Heat” including cooking;



I paid more in Bern @ Starbucks back in 2011 for our coffee stop.




You could have a very basic electrical system. Conservation might be the key for you. I can run down the science for you, but “heat” by battery power is not conservative.

If you have a detailed use planned for your van ( not just electrical ) & post it here, I might be able to help.