lifepo4 transition from Lead Acid.

[Ruso]

Gentlemen,
The subject beaten to death already. If you can please advise and don't laugh.
1. Environment
House bank (4 golf cart 6V batteries) and starter battery (lead acid) in parallel.
Switch (All-None-House-starter)control discharge side - not charge side.
Solar Zamp ZS-30A - supports Lithium (one bank)
Engine: some totally dumb alternator on Perk 4.108 charging both banks
Shore charge Xantrex TrueCharge 12v 40A Battery Charger (no support for Lithium)

Planned Mods.
House Lithium, starter AGM(???)
Solar: two banks solar controller ZAMP SOLAR ZS30AD One for house another for start battery.
Engine: DC to DC from starter battery
Shore: Need charger to support 2 banks, one Lithium another AGM
Questions:
1. Solar (two banks controller): In case DC - DC (starter battery to Lithium) Should I disconnect it if Solar charge is active (two banks) OR just configure solar to starter battery only and let Dc-DC handle house bank?
2. Shore power: should I charge starter AGM battery and let Dc- to DC handle the rest?
Many thanks

[Cheyne]

Victron inverter/chargers, like my Quattro, have a second charger for a starter batter.

Why turn off the solar when charging with the DCDC. Why not charge with both. If they are any good they will work together. Victron with DVCC turned on in a Cerbo does a shared voltage. Mine go from Bulk to Absorbtion to Float together.

Cheyne

[barcoMeCasa]

One thought, I'd be looking at ditching the regulator for victron MPPT and a smartshunt. Much more accurate as the regulators know what the battery voltage really is from the smartshunt, & the datasheet looked very limited & not very accurate or with adjustable voltage control...


2-5 Absorption charging voltage at 25*C
--LTO type battery 14.0 +/-0.2 VDC
--Gel type battery 14.1 +/-0.2 VDC
--LiFePO4 battery 14.4 +/-0.2 VDC

[Ruso]

Originally Posted by Cheyne

Victron inverter/chargers, like my Quattro, have a second charger for a starter batter.

Why turn off the solar when charging with the DCDC. Why not charge with both. If they are any good they will work together. Victron with DVCC turned on in a Cerbo does a shared voltage. Mine go from Bulk to Absorbtion to Float together.

Cheyne

I don't need more inverters - I have 2 already.
If my Xantrex TrueCharge 12v 40A Battery Charger (configured as AGM) charging starter battery can DC to DC handle my house bank?

[Cheyne]

Originally Posted by Ruso

I don't need more inverters - I have 2 already.
If my Xantrex TrueCharge 12v 40A Battery Charger (configured as AGM) charging starter battery can DC to DC handle my house bank?

Well then have fun with it.

Cheyne

[CaptainRivet]

Originally Posted by Ruso

Gentlemen,
The subject beaten to death already. If you can please advise and don't laugh.
1. Environment
House bank (4 golf cart 6V batteries) and starter battery (lead acid) in parallel.
Switch (All-None-House-starter)control discharge side - not charge side.
Solar Zamp ZS-30A - supports Lithium (one bank)
Engine: some totally dumb alternator on Perk 4.108 charging both banks
Shore charge Xantrex TrueCharge 12v 40A Battery Charger (no support for Lithium)

Planned Mods.
House Lithium, starter AGM(???)
Solar: two banks solar controller ZAMP SOLAR ZS30AD One for house another for start battery.
Engine: DC to DC from starter battery
Shore: Need charger to support 2 banks, one Lithium another AGM
Questions:
1. Solar (two banks controller): In case DC - DC (starter battery to Lithium) Should I disconnect it if Solar charge is active (two banks) OR just configure solar to starter battery only and let Dc-DC handle house bank?
2. Shore power: should I charge starter AGM battery and let Dc- to DC handle the rest?
Many thanks

1. connect zamp solar to lithium and AGM, I assume they are separated and you can define different charge Profils per bank. It’s PWM but very handy to be able to charge both banks from solar, don‘t no any MPPT that’s capable of that. Would be interesting to see a 30A Victron MPPT and this Zamp in comparison to see how much you loose.
Connect alternator to AGM and via DC2DC to lithium, and the remote/ignition wire to the ignition switch of engine so the DC2DC only works when engine is on. DC2DC on lithium Profil. Otherwise the mppt also triggers DC2DC on what you don‘t want. In this case solar always floats the AGM starter, also when at dock even without shorepower.
2. connect shorepower to lithium house, solar floats starter enough to be full all the time even if quite clouded. You need another shore charger as AGM is not compatible and trick it to cut off with eg a VSR at eg 13.6V will be as expensive if you buy a 30A Victron LFP capable shore charger.

[Ruso]

Originally Posted by CaptainRivet

1. connect zamp solar to lithium and AGM, I assume they are separated and you can define different charge Profils per bank. It’s PWM but very handy to be able to charge both banks from solar, don‘t no any MPPT that’s capable of that. Would be interesting to see a 30A Victron MPPT and this Zamp in comparison to see how much you loose.
Connect alternator to AGM and via DC2DC to lithium, and the remote/ignition wire to the ignition switch of engine so the DC2DC only works when engine is on. DC2DC on lithium Profil. Otherwise the mppt also triggers DC2DC on what you don‘t want. In this case solar always floats the AGM starter, also when at dock even without shorepower.
2. connect shorepower to lithium house, solar floats starter enough to be full all the time even if quite clouded. You need another shore charger as AGM is not compatible and trick it to cut off with eg a VSR at eg 13.6V will be as expensive if you buy a 30A Victron LFP capable shore charger.

Thank you. Unfortunately starter and home are on one circuit - the both flooded. Another problem I have 2 ignitions and wiring very old - don't really want to make it ignition rewire project. Bottom line is starter should be isolated from home and house bank charged only via DC2DC when engine running - I can put on/off switch and engage it when engine is running. Zamp solar controller with two banks or get another one the same I have - controller per starter and house. Shore power charger with two banks or leave Xantrex TrueCharge for starter only and buy one more lifepo4 for house. I prefer to run generator connected to AC boat system instead of engine to charge both banks. Still don't understand why every charging circuit can't go to starter battery and house bank charged via DC2DC. May be my luck of knowledge how DC2DC operates. How input voltage affecting it's work plan? What it does when no charging at all to starter battery? Draining it?

[newhaul]

Originally Posted by Ruso

Gentlemen,
The subject beaten to death already. If you can please advise and don't laugh.
1. Environment
House bank (4 golf cart 6V batteries) and starter battery (lead acid) in parallel.
Switch (All-None-House-starter)control discharge side - not charge side.
Solar Zamp ZS-30A - supports Lithium (one bank)
Engine: some totally dumb alternator on Perk 4.108 charging both banks
Shore charge Xantrex TrueCharge 12v 40A Battery Charger (no support for Lithium)

Planned Mods.
House Lithium, starter AGM(???)
Solar: two banks solar controller ZAMP SOLAR ZS30AD One for house another for start battery.
Engine: DC to DC from starter battery
Shore: Need charger to support 2 banks, one Lithium another AGM
Questions:
1. Solar (two banks controller): In case DC - DC (starter battery to Lithium) Should I disconnect it if Solar charge is active (two banks) OR just configure solar to starter battery only and let Dc-DC handle house bank?
2. Shore power: should I charge starter AGM battery and let Dc- to DC handle the rest?
Many thanks

Ok all above sounds good. shore charger keep it separate charge house and get a small 10 amp guest charger set to charge the start bank .

Solar. Run it all in to charge the lifepo4 house bank.

[Ruso]

Originally Posted by newhaul

Ok all above sounds good. shore charger keep it separate charge house and get a small 10 amp guest charger set to charge the start bank .

Solar. Run it all in to charge the lifepo4 house bank.

Thank you. Extra shore AGM starter battery charger is not a problem. I still need shore charger for lifepo4 house. I was hoping DC2DC will take care of house bank charging when existing shore charger charges starter in AGM configuration.
It seems I still need On/Off switch to isolate starter/house batteries when not under motor. Don't know how DC2DC operates and concerned it might drain starter battery via DC2DC when no engine running. Right?

[newhaul]

Originally Posted by Ruso

Thank you. Extra shore AGM starter battery charger is not a problem. I still need shore charger for lifepo4 house. I was hoping DC2DC will take care of house bank charging when existing shore charger charges starter in AGM configuration.
It seems I still need On/Off switch to isolate starter/house batteries when not under motor. Don't know how DC2DC operates and concerned it might drain starter battery via DC2DC when no engine running. Right?

No not correct
Dc2dc require a specific minimum voltage to turn on for charging
Secondly in our installs there is an ignition sense wire that gets wired to the run position of the switch turning the unit on or off with the engine

[Ruso]

Originally Posted by newhaul

No not correct
Dc2dc require a specific minimum voltage to turn on for charging
Secondly in our installs there is an ignition sense wire that gets wired to the run position of the switch turning the unit on or off with the engine

Thank you. Assuming the sense wire going to alternator or ignition. Which one?

[HeinSdL]

Originally Posted by Ruso

Thank you. Assuming the sense wire going to alternator or ignition. Which one?

The victron dcdc (not familiar with other brands) can be set up to only run if the source battery has a voltage above a threshold, ie only when engine is running. So the sense wire is not strictly necessary but it can be connected to the ignition to be double sure the dcdc is off when the engine is off. In my case I have not done that, was no need.

[Ruso]

Originally Posted by HeinSdL

The victron dcdc (not familiar with other brands) can be set up to only run if the source battery has a voltage above a threshold, ie only when engine is running. So the sense wire is not strictly necessary but it can be connected to the ignition to be double sure the dcdc is off when the engine is off. In my case I have not done that, was no need.

Makes sense. My alternator produces about 14.5 - 14.7 than if set Victron cut of voltage to 14 it should work. Is Victron has some kind of visual indicator being OFF or ON mode? Thank you.

[HeinSdL]

Originally Posted by Ruso

Makes sense. My alternator produces about 14.5 - 14.7 than if set Victron cut of voltage to 14 it should work. Is Victron has some kind of visual indicator being OFF or ON mode? Thank you.

Well I have a shunt on the output of the dcdc which goes to a Simarine screen where I monitor things. But there's also the victron app which you can use to see what is going on via bluetooth. As well as some lights on the unit itself which I haven't actually looked at closely, yet.

One thing to be aware of when setting up the charger to automatically detect engine running is losses in the wiring. If the charger is not near the engine and (importantly as I discovered) if the wires from the alternator itself to the start battery are undersized (they may well be) then the charger may not see a particularly high voltage once it starts drawing current. In my case a cut off voltage of around 13V works well. With the engine running I measured the alternator putting out 14.4V but the charger, drawing up to 50A was seeing around 13.1V. So with the engine off and input voltage dropping off, once below 13V the charger shuts down. Using the original factory installed alternator wiring the auto detect on the victron dcdc charger did not work at all.

[newhaul]

Originally Posted by Ruso

Thank you. Assuming the sense wire going to alternator or ignition. Which one?

The sense wire goes to the run position of the ignition.
Myself I also have a switch in that wire for when I don't need to charge lifepo4 house or I need all of the hp out of my little iron wind.
On my renogy unit there is also the ability to limit the dc2dc to half of its rating. I have that wired up with a switch as well for charging at a lower rate when motoring longer distances. .
Dm me your email and I will forward the pdf of the tech manual for my renogy 40amp dc2dc it also covers the 20 amp and the 60 amp units
Rob SV Stephfen Ulysses