Van of enormous power Mk 4

[Joeboy]

Well that's the buying fun out of the way. A question for any van owners or knowledgable folk. As I have an existing LB set up in the van I shouldn't need any extra control or relays?

Or do I?

My thinking is
The solar controller takes care of battery charge so as not to.overcharge whether as LA or lifepo4 (I choose setting in app) and the 12.8V of the potential lifepo4 is close enough in V rating to a LA. 14.4V or so off the alternator shouldn't cause a problem as the onboard bms will kick in if need be.

Anything else I'm missing?

Edit- interesting guide. I'll have a good look around the van and see what was fitted.

https://www.12voltplanet.co.uk/split-ch ... X6Ku6ewUnc

How are the systems setup at the moment?

Basically there are 3 options:
- Completely separate. Easiest way to do things but you lose the opportunity to charge the leisure battery from the alternator or the starter from the solar.
- Always connected. Basically the same as having a bigger starter battery. You risk draining the starter battery with the house loads.
- some sort of smart connection/disconnection. Traditionally this is a timer relay so the two systems are connected once the ignition has been on for 5-mins (or whatever) and disconnects the moment the ignition is turned off. Other people have a switch on the dash controlling a relay but this is open to human error.

I'm hoping that I can easily find a n/o relay in there somewhere in the engine bay. So far I've just used the van and sussed out the switches. We have a habitation switch & fuse board combined for 12V or ehu. I'll have a dig about and see what's what. Home on Thursday but there may be an alternative worklist to get through first.

[Stinsy]

If you put a multimeter on the positive of the leisure and starter batteries and set it to check continuity you'll find out.

[Joeboy]

If you put a multimeter on the positive of the leisure and starter batteries and set it to check continuity you'll find out.

True but I'm an eyes on type person. I like to work my way around a system and see it. I've already started in on the underbonnet last time home. Removed some old brackets, stripped out and cleaned the rad exp bottle.

Good call though, cheers!

[Joeboy]

Inverter& solar charge controller arrived, woohoo!

Gathered info that I'll need a dc-dc controller to protect the alternator from the lifepo4 potenyial draw. I think that's what Stinsy was saying the other week?

A nice circular deal there as it puts me back at Victron Orion gear again! Panels should arrive tomorrow. SWMBO is talking about Poland & Latvia in the RV, exciting times.

[Stinsy]

Inverter& solar charge controller arrived, woohoo!

Gathered info that I'll need a dc-dc controller to protect the alternator from the lifepo4 potenyial draw. I think that's what Stinsy was saying the other week?

A nice circular deal there as it puts me back at Victron Orion gear again! Panels should arrive tomorrow. SWMBO is talking about Poland & Latvia in the RV, exciting times.

Correct. Basically while the internal resistance of Lead is low, LiFePO4 can be ultra-low. This causes a problem whereby at idle the battery will pull more power than the alternator can happily deliver. This will let the smoke out of the alternator.

Like most “problems” there are several mitigations:
- You can spin the alternator faster with a different pulley.
- You can introduce a bit of resistance to the circuit (10-20mΩ = 1m of 1mm² earth stripped out of some T+E is perfect).
- You can find a way of connecting the alternator to the LiFePO4 only when the engine is running at driving speeds.

[Joeboy]

Inverter& solar charge controller arrived, woohoo!

Gathered info that I'll need a dc-dc controller to protect the alternator from the lifepo4 potenyial draw. I think that's what Stinsy was saying the other week?

A nice circular deal there as it puts me back at Victron Orion gear again! Panels should arrive tomorrow. SWMBO is talking about Poland & Latvia in the RV, exciting times.

Correct. Basically while the internal resistance of Lead is low, LiFePO4 can be ultra-low. This causes a problem whereby at idle the battery will pull more power than the alternator can happily deliver. This will let the smoke out of the alternator.

Like most “problems” there are several mitigations:
- You can spin the alternator faster with a different pulley.
- You can introduce a bit of resistance to the circuit (10-20mΩ = 1m of 1mm² earth stripped out of some T+E is perfect).
- You can find a way of connecting the alternator to the LiFePO4 only when the engine is running at driving speeds.

Or and I hope this is correct, I can install an inline orion dc to dc unit and that will control the flow of power from alternator to lifepo4. I can see small busbars coming in handy here as the battery area itself is going to become congested.

I am aiming for the system to be fit & forget. I'll get it to LA/solar operating first then look to step up to lifepo4 once I've lived with LA for a wee bit.

Heading up the road today and woke up dreaming about laying out the gear in the garden to test! It went well!

[Stinsy]

Inverter& solar charge controller arrived, woohoo!

Gathered info that I'll need a dc-dc controller to protect the alternator from the lifepo4 potenyial draw. I think that's what Stinsy was saying the other week?

A nice circular deal there as it puts me back at Victron Orion gear again! Panels should arrive tomorrow. SWMBO is talking about Poland & Latvia in the RV, exciting times.

Correct. Basically while the internal resistance of Lead is low, LiFePO4 can be ultra-low. This causes a problem whereby at idle the battery will pull more power than the alternator can happily deliver. This will let the smoke out of the alternator.

Like most “problems” there are several mitigations:
- You can spin the alternator faster with a different pulley.
- You can introduce a bit of resistance to the circuit (10-20mΩ = 1m of 1mm² earth stripped out of some T+E is perfect).
- You can find a way of connecting the alternator to the LiFePO4 only when the engine is running at driving speeds.

Or and I hope this is correct, I can install an inline orion dc to dc unit and that will control the flow of power from alternator to lifepo4. I can see small busbars coming in handy here as the battery area itself is going to become congested.

I am aiming for the system to be fit & forget. I'll get it to LA/solar operating first then look to step up to lifepo4 once I've lived with LA for a wee bit.

Heading up the road today and woke up dreaming about laying out the gear in the garden to test! It went well!

Sure. It comes down to a 1p piece of wire vs a £300 DCDC converter I guess...

[Joeboy]

Correct. Basically while the internal resistance of Lead is low, LiFePO4 can be ultra-low. This causes a problem whereby at idle the battery will pull more power than the alternator can happily deliver. This will let the smoke out of the alternator.

Like most “problems” there are several mitigations:
- You can spin the alternator faster with a different pulley.
- You can introduce a bit of resistance to the circuit (10-20mΩ = 1m of 1mm² earth stripped out of some T+E is perfect).
- You can find a way of connecting the alternator to the LiFePO4 only when the engine is running at driving speeds.

Or and I hope this is correct, I can install an inline orion dc to dc unit and that will control the flow of power from alternator to lifepo4. I can see small busbars coming in handy here as the battery area itself is going to become congested.

I am aiming for the system to be fit & forget. I'll get it to LA/solar operating first then look to step up to lifepo4 once I've lived with LA for a wee bit.

Heading up the road today and woke up dreaming about laying out the gear in the garden to test! It went well!

Sure. It comes down to a 1p piece of wire vs a £300 DCDC converter I guess...

Fair point, it's £130 though for one. I'd rather have a known component in there. The more me n swmbo chat the more likely it looks we'll be going further East than before and for that it's belts & braces time along with strong self reliance.

I'm like a kid right now. Desperate to get home and open my Christmas presents! I'll set it all up on short 6mm pv cable runs in garden (marked up to avoid magic smoke) and test inverter with a 400 to 500W load on a resistive heater. I've got the old 12V battery out the transit connect that was showing signs of failure at minus 11 before replacement. My first bifacial panels, woohoo!

[Stinsy]

Or and I hope this is correct, I can install an inline orion dc to dc unit and that will control the flow of power from alternator to lifepo4. I can see small busbars coming in handy here as the battery area itself is going to become congested.

I am aiming for the system to be fit & forget. I'll get it to LA/solar operating first then look to step up to lifepo4 once I've lived with LA for a wee bit.

Heading up the road today and woke up dreaming about laying out the gear in the garden to test! It went well!

Sure. It comes down to a 1p piece of wire vs a £300 DCDC converter I guess...

Fair point, it's £130 though for one. I'd rather have a known component in there. The more me n swmbo chat the more likely it looks we'll be going further East than before and for that it's belts & braces time along with strong self reliance.

I'm like a kid right now. Desperate to get home and open my Christmas presents! I'll set it all up on short 6mm pv cable runs in garden (marked up to avoid magic smoke) and test inverter with a 400 to 500W load on a resistive heater. I've got the old 12V battery out the transit connect that was showing signs of failure at minus 11 before replacement. My first bifacial panels, woohoo!

Cool, I was looking at the 50A one, the 18A version is a bit cheaper.

[Joeboy]

Smallest solar panel owned is now the gizit keyring torch from Photonic universe retailer, love it! It's going on the van keyring.