Victron DC-DC doesn’t appear to be charging LB

[roadtripper]

I'm starting to suspect the output stage of your charger.

The settings look rational.

Are you able to remove input power from the charger and restart it?

 

[Euge]

Checked the inline fuse from charger to battery and that’s ok

 

[Euge]

I'm starting to suspect the output stage of your charger.

The settings look rational.

Are you able to remove input power from the charger and restart it?

I’d have to remove the supply from battery. Is that worth a go?

We will getting ferry in an hour and luckily have EHU tonight.

 

[roadtripper]

I think it's worth a try restarting it if you are able to. Give it a few minutes off and then reconnect it.

 

[Euge]

I think it's worth a try restarting it if you are able to. Give it a few minutes off and then reconnect it.

We’re back up to 12.7v on the EHU mains charger. That’s normally what I get. Disconnected the battery power feed expecting it to power off and the app shows it’s still live with 5.7 v. Presumably from the LB. I wasn’t expecting that. So I can’t reset here without getting all the connections off the LB.

 

[Salty Spuds]

We’re back up to 12.7v on the EHU mains charger. That’s normally what I get. Disconnected the battery power feed expecting it to power off and the app shows it’s still live with 5.7 v. Presumably from the LB. I wasn’t expecting that. So I can’t reset here without getting all the connections off the LB.

Correct me if I’m wrong, but are you saying that the LB is only showing 5.7V, and that 12.7V is your “normal” voltage shown on the Leisure Battery when on EHU? If so, those numbers are way off. I’m leaning towards a knackered LB. The LB should be showing 12V+, and I’d expect to see 13-14V on the mains charger after an hour or so.

 

[roadtripper]

We’re back up to 12.7v on the EHU mains charger. That’s normally what I get. Disconnected the battery power feed expecting it to power off and the app shows it’s still live with 5.7 v. Presumably from the LB. I wasn’t expecting that. So I can’t reset here without getting all the connections off the LB.

Do you have a screenshot of the app in that state - which is the 5.7v against the input voltage or the output voltage?

I wouldn't expect the charger to run itself from the output but I don't have one myself, maybe @Dellmassive can clarify.

Either way 5.7v is a distinctly odd voltage to be getting in a 12v vehicle/leisure system.

 

[roadtripper]

Correct me if I’m wrong, but are you saying that the LB is only showing 5.7V, and that 12.7V is your “normal” voltage shown on the Leisure Battery when on EHU? If so, those numbers are way off. I’m leaning towards a knackered LB. The LB should be showing 12V+, and I’d expect to see 13-14V on the mains charger after an hour or so.

If 12.7 is the resting voltage with the charger OFF then that's a believable voltage for an AGM battery (which is what your DC-DC settings show) but if that's on charge I'd second @Salty Spuds that that's lower than expected.

Do you have a picture of your LB to clarify which type you have?

 

[DXX]

Possibly nothing to do with your case but recently I replaced my vans 8 year old vehicle battery as I had some electrical issues. Once it was replaced the leisure battery performance was greatly increased.
The old vehicle battery probably had an internal short and the leisure battery wasn’t getting the required B2B charge.

 

[Euge]

Correct me if I’m wrong, but are you saying that the LB is only showing 5.7V, and that 12.7V is your “normal” voltage shown on the Leisure Battery when on EHU? If so, those numbers are way off. I’m leaning towards a knackered LB. The LB should be showing 12V+, and I’d expect to see 13-14V on the mains charger after an hour or so.

No the LB is charged up to 12.7v on EHU.

When I disconnected the DC DC from the van battery I was expecting it to go dead and then reset. But the app showed it still had 5.7v so it never reset. I was guessing that the LB was somehow providing power.

Driving today the DC DC is still showing an output. Today it’s over 12v, so is it the case that below 12v output doesn’t add any charge to the LB?

 

[Salty Spuds]

No the LB is charged up to 12.7v on EHU.

When I disconnected the DC DC from the van battery I was expecting it to go dead and then reset. But the app showed it still had 5.7v so it never reset. I was guessing that the LB was somehow providing power.

Driving today the DC DC is still showing an output. Today it’s over 12v, so is it the case that below 12v output doesn’t add any charge to the LB?
View attachment 244024

Does the LB ever get higher than 12.7V? That still looks wrong to me. The LB should be getting up to 14.7V or thereabouts. If it’s sticking at 12.7-13V then I suspect a duff LB.

 

[Euge]

Does the LB ever get higher than 12.7V? That still looks wrong to me. The LB should be getting up to 14.7V or thereabouts. If it’s sticking at 12.7-13V then I suspect a duff LB.

It’s at 13.1v , I suspect you might be right. I’ve never seen it higher. Is that a reason it’s not accepting dc charge?

 

[Salty Spuds]

It’s at 13.1v , I suspect you might be right. I’ve never seen it higher. Is that a reason it’s not accepting dc charge?

If the battery is goosed, it won’t accept charge. Leisure batteries have a hard life & need managing correctly to get the best out of them, especially Lead Acid. It takes very little to ruin them, a couple of deep discharges & it’s good night Vienna.

 

[roadtripper]

Not just discharges - though that's most likely - they can also be damaged by overcharging if set up as the wrong battery type.

 

[Euge]

We’re back and managed to get EHU all but one day. LB got up to 14.4v unloaded, on EHU which looks about right.

The DC DC charger isn’t adding anything at all that I can see. It’s an 18A Victron smart. Maybe need to check all the cable connections now I’m back, but there’s not much to check and visually it all looks fine. Is there a way to check the output with a voltmeter? Can I just put the meter across the output connectors?

 

[Salty Spuds]

We’re back and managed to get EHU all but one day. LB got up to 14.4v unloaded, on EHU which looks about right.

The DC DC charger isn’t adding anything at all that I can see. It’s an 18A Victron smart. Maybe need to check all the cable connections now I’m back, but there’s not much to check and visually it all looks fine. Is there a way to check the output with a voltmeter? Can I just put the meter across the output connectors?

If the LB is at 14.4V it’s fully charged & the Orion won’t do anything. If you look on the app, what does it say the Orion is doing?

 

[roadtripper]

The way I'd check is with a DC clamp multimeter - I use the UNI-T one.

Not super cheap but very good value and very handy when looking after 12v wiring.

 

[Euge]

If the LB is at 14.4V it’s fully charged & the Orion won’t do anything. If you look on the app, what does it say the Orion is doing?

That’s the maximum voltage it got to, so probably not a duff battery.
I drove 8 hours yesterday and set off with 12.5v on the LB. The Orion shows 12.1v output but there was no change in LB voltage over the whole drive. I’d have expected some increase.

 

[roadtripper]

I would check your wiring and fuse holders for potential poor connections and high resistance - every thing connected to the battery should be showing the same voltage, so if one is not then that's the one to look at.

Small differences of a couple of tenths of a volt are not a worry as likely just different calibration, but if you are seeing 12.1v on the Orion's connection but 14.4v presumably from your battery BMS or mains charger data - that's hard to explain.

Do you have solar at all? What does that show about the state of the battery (if it can show that)

 

[Euge]

Turns out the Victron DCDC was faulty! Waiting for a replacement to arrive.

Thanks everyone for your help and support. It’s so good to have people out there when you are in a bit of a pickle.