[Guide] DC-DC Charger (for leisure battery) -- How I Done It --

[brenmona]

Hi @TallPaul_S. Yes, Thankyou, I do know the converter company changed the black wire over when he changed to the lithium battery. It just seems that the Ctek will not allow over 13.2v to get through to the battery when charging off solar

Thanks again

 

[brenmona]

I just connected the black battery select wire to the SB input on the CTEK unit when I did mine.
Just checked my Renogy app and it’s showing 100% at 13.2v.
What are we saying the LiFePo voltage should be?

I thought and `I could be wrong that Lithium was around the 14.2 Volt resting?

 

[TallPaul_S]

I thought and `I could be wrong that Lithium was around the 14.2 Volt resting?

LiFePO4 at 100% SOC is 14.2v when charging and 13.5v when not charging. Depending on battery of course, but they're all close to that figure.

 

[Bigsidavies]

Hi @TallPaul_S. Yes, Thankyou, I do know the converter company changed the black wire over when he changed to the lithium battery. It just seems that the Ctek will not allow over 13.2v to get through to the battery when charging off solar

Thanks again

Although I have the CTEK250SE my solar is managed with a Victron MPPT controller. Even over summer I don't think I ever saw more than 13.4V in the battery.
You got me wondering now, so I'm going to connect it to EHU tomorrow and see what the victron ac-dc takes the voltage to.

Edit:- just found this on the Renogy website which shows that a fully charged battery at rest should be 13.6v

A Comprehensive Guide to LiFePO4 Voltage Chart

Unlease the secrets of LiFePO4 battery voltage and learn charge cycles, optimal usage and performance in our guide.

www.renogy.com

 

[Salty Spuds]

Although I have the CTEK250SE my solar is managed with a Victron MPPT controller. Even over summer I don't think I ever saw more than 13.4V in the battery.
You got me wondering now, so I'm going to connect it to EHU tomorrow and see what the victron ac-dc takes the voltage to.

I found that the standard Victron lithium profile didn’t get my SuperB Epsilon battery high enough to reset the SOC to 100% on the BMS. I contacted SuperB & they sent me some charging figures, Voltage/time etc. I setup a custom profile on my Victron app & used it across all 3 devices, solar/mains/B2B. Works a treat.

 

[TallPaul_S]

Although I have the CTEK250SE my solar is managed with a Victron MPPT controller. Even over summer I don't think I ever saw more than 13.4V in the battery.
You got me wondering now, so I'm going to connect it to EHU tomorrow and see what the victron ac-dc takes the voltage to.

Edit:- just found this on the Renogy website which shows that a fully charged battery at rest should be 13.6v

A Comprehensive Guide to LiFePO4 Voltage Chart

Unlease the secrets of LiFePO4 battery voltage and learn charge cycles, optimal usage and performance in our guide.

www.renogy.com

What you'll typically see, if you have any load at all on the battery, is it going to 14.2v when it's charging, but it'll only be there very briefly before dropping to 13.5/6v - then if you have any load it'll drop a little more to 13.3/13.4v.

Like so:


In the above chart, mine only sat at 13.5v for about an hour, that's with a 0.5a draw on it - and it started dropping away when any solar input would have also gone.

So you might never see the battery at 14.2 or 13.5/6v as it'll only ever be there briefly - but it must be getting to that voltage otherwise it's not getting fully charged.

Mine currently is at 99% SOC and only 13.35v.

 

[Bigsidavies]

I found that the standard Victron lithium profile didn’t get my SuperB Epsilon battery high enough to reset the SOC to 100% on the BMS. I contacted SuperB & they sent me some charging figures, Voltage/time etc. I setup a custom profile on my Victron app & used it across all 3 devices, solar/mains/B2B. Works a treat.

I’ve got my mppt on a custom profile as attached. But that’s only 14.2v.
The Renogy document above shows 14.6v to be max charge voltage so I’ll change it to that.
Won’t really do much for a few months, but I’ll check the Victron 240v charger settings tomorrow.

 

[Bigsidavies]

Just plugged in to EHU and the LiFePo profile on the Victron blue smart is also 14.2v.
I’ve changed it to 14.6 on both the solar and the 240 and I’ll see what happens.
Hopefully it will get the battery to the 13.6 max at rest.

 

[PaddyC]

Dell, I’m literally just starting a conversion (fitted all new LED external lights, put windows in the barn and sliding doors and am currently sound deadening and insulating the interior.
I’ve bought a ‘Bluetti charger one’ to dc/dc charge my AC200L battery pack when driving.
I’m going to install it today via the firewall grommet to the battery.
Have you any thoughts / advice on this unit or help for me in general on fitting this?

 

[TallPaul_S]

FYI those with Orion XS 50a - just had a helpful email from Victron telling me to update from v1.07 to v1.08 as there was an issue with v1.07. Love the VRM portal!!!

 

[n10n]

FYI those with Orion XS 50a - just had a helpful email from Victron telling me to update from v1.07 to v1.08 as there was an issue with v1.07. Love the VRM portal!!!

View attachment 270455

Maybe I should take a look into that. A little while back I used Victron app after not opening it for a looooooong time. I was a bit disheartened for a forced firmware upgrade - not really a problem but I gringe always if I can’t use something before upgrading.

 

[TallPaul_S]

Maybe I should take a look into that. A little while back I used Victron app after not opening it for a looooooong time. I was a bit disheartened for a forced firware upgrade - not really a problem but I gringe always if I can’t use something before upgrading.

View attachment 270458

One of the many advantages of having a cerbo GX and VRM - I can update firmware from anywhere in the world. Just done it on my Orion XS and my Cerbo GX from my laptop in the house. Sod going outside!

 

[Dellmassive]

looks like VRM will allow the 1.08.

But the app sticks with 1.06.

But all done now.....

.



..

 

[Dellmassive]

Dell, I’m literally just starting a conversion (fitted all new LED external lights, put windows in the barn and sliding doors and am currently sound deadening and insulating the interior.
I’ve bought a ‘Bluetti charger one’ to dc/dc charge my AC200L battery pack when driving.
I’m going to install it today via the firewall grommet to the battery.
Have you any thoughts / advice on this unit or help for me in general on fitting this?

Follow the OEM cable guide.

..

Tpi 2046279, T6 Repair Instructions For Voltage Supply Of 2nd Battery

TPI: 2046279, T6: repair instructions for voltage supply of 2nd battery Tool and components: - Cable for 2nd battery 16mm² (7E0.971.044) - Corrugated tube (N.107.326.01) - Cable tie (N.106.622.01 or similar) - Grommet (2D0.906.376.S) - Butyl (AKL.450.005.05) - Wrapping tape - Holder of...

www.t6forum.com

..

But take it from the starter battery POs terminal.

And NEG to the van chassis.

 

[n10n]

looks like VRM will allow the 1.08.

But the app sticks with 1.06.

Very weird but seems the app has to be updated for it to get new firmwares

 

[TallPaul_S]

Very weird but seems the app has to be updated for it to get new firmwares

View attachment 270490

Tbh it makes sense, the devices have no connection to the internet so the firmware updates are done via the app as this has both a connection to the internet and to the device. It's probably easier to control the updates via app updates too.

If you have VRM this means the devices have access to the internet so no app required.

 

[n10n]

Tbh it makes sense, the devices have no connection to the internet so the firmware updates are done via the app as this has both a connection to the internet and to the device.

Yeah, but the app could just check for new version from internet upon connecting to the device.

I was thinking maybe they want to keep app and firmware in sync - if for example they add a new configuration option in fw app would not know how to show it without updating.

Anyway, not a big deal, just little bit surprising and means app users are always lagging a bit with updates (which might be good when buggy updates are released )