DC-DC Charger Issue

[sshouse]

I have a Victron Orion Smart DC-DC charger. The Victron Connect app is currently showing charge is disabled due to low voltage lockout. 12.5.v I am hoping to get an idea of the source and cause of the problem.

[booster]

Originally Posted by sshouse

I have a Victron Orion Smart DC-DC charger. The Victron Connect app is currently showing charge is disabled due to low voltage lockout. 12.5.v I am hoping to get an idea of the source and cause of the problem.

If it is for lithium batteries charging at that low a voltage may be lower than the safety lockout point of the the charger setting or the BMS setting if interconnected system. If it is lithium and that low you will probably need to either get to the "activation" method of the system or charge up a bit with a power supply type charger.

[The Eyesore]

Is the low voltage lockout occurring with the engine running?

What the lockout is doing is trying to save your engine battery so that you don't deplete it, charging the house battery.

If the van is not running, this would be the correct behavior. If the van IS running (preferrably driving, not just idling), it would seem that your alternator isn't up to the task or has possibly failed. 12.5V is about what voiltage your battery should have when sitting WITHOUT the alternator charging it. With the engine running and the alternator charging, you should have about 13.5V-14.5V, ideally.

You'll get better help with more information.

Vehicle: year, make, model? Has the Victron system worked successfully prior to now? Have you made any recent changes? Maybe you can attach a screen grab of the Victron app showing the charge state?

[booster]

I see that the OP has 2014 210 Roadtrek which would not have come with anything Victron in it, so has to be a later upgrade install. The upgrades, if done recently would commonly include the DC to DC charger, lithium batteries with a Victron BMS if the batteries are also Victron, and possibly a Victron Cerbo and monitor. Of course it could be just the B to B also or some combination. A 12.5v lockout on the B to B would most likely to indicate a lithium setup. A starting battery, the will almost always be a wet cell, will be near full at 12.5v so that should not be involved in getting charging to the coach as the B to B will isolate them.



Hopefully, the OP can fill us in on what the system is and what has been tried to get it up and running. First guess is that it is just low coach batteries and pretty easy to fix with a non smart charger or connection the engine charging by bypassing the B to B.

[sshouse]

Originally Posted by booster

If it is for lithium batteries charging at that low a voltage may be lower than the safety lockout point of the the charger setting or the BMS setting if interconnected system. If it is lithium and that low you will probably need to either get to the "activation" method of the system or charge up a bit with a power supply type charger.

It is a lithium system. The charger was set at the default, 12.5 lockout/12.8 resume. I changed the settings to 12.4 lockout/12.5 resume and the charger works as expected.

[booster]

Originally Posted by sshouse

It is a lithium system. The charger was set at the default, 12.5 lockout/12.8 resume. I changed the settings to 12.4 lockout/12.5 resume and the charger works as expected.

Excellent result, and easy/free.


Was your lithium bank at 12.5v or was it looking at the starting battery?

[sshouse]

Originally Posted by booster

Excellent result, and easy/free.


Was your lithium bank at 12.5v or was it looking at the starting battery?

It was looking at the starting battery. It is a resting at 12.48.

The system had been working correctly. I am going to keep tabs on the starting battery and have the alternator checked

[booster]

Originally Posted by sshouse

It was looking at the starting battery. It is a resting at 12.48.

The system had been working correctly. I am going to keep tabs on the starting battery and have the alternator checked

That is very interesting that it does it off that battery. Most of the systems I recall seeing described have the B to B start and connect based on a signal from the engine "run" side of the ignition or from the PCM. They would also have a lockout for the lithium in many cases based on temp and voltage or either.


Is the system rigged with two outputs from the B to B so it charges the starting battery through it instead of direct from the engine?

[booster]

I have been trying to figure out why and how you would ever want a B to B between the engine and the lithium pack to be connected at ever 12.5v or lower. You generally would only want a B to B on when the engine is running, just like with a separator in a lead acid setup, and that would be set at something like 13.1v so only connected when the engine was running. Perhaps it is because they worry about the the lithiums pulling the alternator voltage down to as low as 12.5v, but that would also mean that the alternator is either too small or turned down because of heat issues and that type of thing isn't good to have.


If you are getting only 12.48v with the B to B not connected to the lithium pack, you must have some sort of charging issue with van side of system. I don't see why resting voltage of the starting battery should matter at all because you don't want it connected if not running.

[@Michael]

Originally Posted by booster

Most of the systems I recall seeing described have the B to B start and connect based on a signal from the engine "run" side of the ignition or from the PCM. They would also have a lockout for the lithium in many cases based on temp and voltage or either.

The Victron Orion's use chassis battery voltage to start/stop the coach battery charging algorithm. The voltage triggers are configurable.

My Redarc is the same, and unlike Victron, it is not configurable/programmable. The now-defunct Amp-L-Start B2B's also use voltage alone.

The Victron and (IRRC) Redarc pause charging every minute or so to allow the B2B to properly measure chassis battery voltage regardless of voltage drop on chassis battery side. I put a solid state relay in line to allow me to disable the Redarc when needed - its charging algorithm isn't configurable to my taste.

If @sshouse has significant voltage drop between the chassis battery and Orion, the Orion's detection routine might not work correctly.

I think this doc is the relevant one: https://www.victronenergy.com/media/...detection.html

[booster]

Cross post here, I must have been typing when Michael posted.



I found some instructions on Victron B to B chargers and I think I may understand the 12.5v setting now. Interesting to be sure and may apply to many of the newer, but not older, vehicles we all have.


Here is a partial quote from the instructions explaining their "engine shutdown detection" feature.





It is from this document in section 5.


https://www.victronenergy.com/media/...detection.html


Engine detection to confirm actual running is a great feature, but newer energy conserving alternator controls look to be giving their setup some issues because of low voltage.


This confirms they do not want the B to B connected when the engine is not running, I think, but when set at 12.5v it easily can be with the engine off depending on the battery condition. It almost certainly will stay connected at initial shutoff of the engine until the starting battery loses it's surface charge.


I don't know what a good solution would be if you have a van controlled alternator that drops that low on regeneration or such because if you turn up the setting to the more normal 13.1v detection you will have the B to B turning on and off a lot during normal driving. If you set it lower like the OP has it will stay connected when not running, which you don't want either, if the engine dies. It probably will disconnect if the key is off, or it should, because the power to the B to B should be coming from a switched, not continuous 12v source off the ignition switch. If it is a push button I don't know where you would find that source, but probably a PCM controlled relay.


If you have an older van, I would just turn up the setting to 13.1v so the B to B can't be on with the engine off.


The better way to sense engine running is to use a "stator/tach" output from the alternator that will show if the engine and alternator are actually turning.

[booster]

Originally Posted by @Michael

The Victron Orion's use chassis battery voltage to start/stop the coach battery charging algorithm. The voltage triggers are configurable.

My Redarc is the same, and unlike Victron, it is not configurable/programmable. The now-defunct Amp-L-Start B2B's also use voltage alone.

The Victron and (IRRC) Redarc pause charging every minute or so to allow the B2B to properly measure chassis battery voltage regardless of voltage drop on chassis battery side. I put a solid state relay in line to allow me to disable the Redarc when needed - its charging algorithm isn't configurable to my taste.

If @sshouse has significant voltage drop between the chassis battery and Orion, the Orion's detection routine might not work correctly.

I think this doc is the relevant one: https://www.victronenergy.com/media/...detection.html

That's interesting especially the stoppage of charge to check chassis battery voltage, I would expect more benefit from checking the the coach batteries to get a more accurate stopping of charge point. I would think that constantly turning on and off the charging would drive PCM controlled alternators nuts



The OP has a Roadtrek 210P, so it may or may not have a pcm controlled alternator, but I don't know if, or when, they do the major voltage reductions in the PCM controlled ones. Our 2007 Chevy was the last of non PCM controlled ones.

[booster]

The OP probably does have the low voltage charging as he has a 2014 210P, it appears.


It looks like you can lock them into higher voltage charging by turning on things like headlights or other items, so might be a good work around that would allow turning up the setting to get the B to B off when the engine is not running.


Here is a link to a discussion forum that explains how the GM system works. Scroll down to a post by Slivery13.


https://www.silveradosierra.com/thre...-volts.351434/

[@Michael]

Originally Posted by booster

That's interesting especially the stoppage of charge to check chassis battery voltage, I would expect more benefit from checking the the coach batteries to get a more accurate stopping of charge point. I would think that constantly turning on and off the charging would drive PCM controlled alternators nuts

The pause is to allow the B2B to determine if the alternator is charging by accurately reading chassis battery voltage - which would otherwise be subject to voltage drop, dependent on wire size & length.

I reviewed the Redarc docs - it pauses for "a split second every 100 seconds to measure the unloaded voltage at the battery". Apparently that's enough to determine if the chassis battery is being charged (or not).

The OP probably does have the low voltage charging as he has a 2014 210P, it appears.

The Orion might be getting fooled by the smart alternator.

[booster]

Originally Posted by @Michael

The pause is to allow the B2B to determine if the alternator is charging by accurately reading chassis battery voltage - which would otherwise be subject to voltage drop, dependent on wire size & length.

I reviewed the Redarc docs - it pauses for "a split second every 100 seconds to measure the unloaded voltage at the battery". Apparently that's enough to determine if the chassis battery is being charged (or not).



The Orion might be getting fooled by the smart alternator.

Do they have dedicated voltage sense wire to starting battery?


I am having a very hard time figuring out why they are worried about the starting battery rested voltage in a system that has an alternator when they can tell if the engine running voltage is above charge voltage. It appears to me that this would be for a true battery to battery charging system with no alternator or other charging to starting battery as then the unloaded voltage of battery would be critical and would give them an idea of what the SOC of it is so they can turn off the charging on time.


If they are looking for voltage drop in the charge line then they would do it during charging with the alternator not with charging off.

[booster]

Reading more detail into the Victron literature, it appears they are mostly concerned with alternator overload, probably because if the smart alternator control turns it down to 12.5v the Orion is going to increase the input to hold the rated output, if it is rated for the full output spec and not the input amps. Since the B to B would normally be the current limiter in the system and should be sized appropriately for that to limit the alternator output to what it can handle continuously when also adding in max type chassis loads, which can be pretty high continuously if the headlights and climate control fan are on. At least the Chevy doesn't have electric fans also.


It is a monitored system so they know the amps to the battery but not total coach load so the B to B has to really be considered to be running at max for long periods. The smart alternator has no idea what is going on because it has the shunt on the starting battery input so it will only see chassis and engine loads. If the alternator temp starts to get too high, it should start to taper field current and thus the output amps, generally also with a voltage drop. Remote regulators like a Balmar will do the same thing off an alternator temp sensor, so I would think the Orion could also be able to do that if they had the sensor on the alternator.


There are lots of single alternator setups with B to B chargers to limit current out there, and if sized properly we just don't hear of alternator failures that I remember. We have seen them on Sprinters that have a very low limit on accessory output (I think some push that though) and they have very complex smart charging protocol.


If the Orion is sized correctly for the alternator, I think it is very possible the engine shutoff could be just turned off and all would fine and trouble free.

[Richard Cranium]

I just put a victron on my 2006 Road Trek. You can configure when the charger shuts off in the app. Some alternators only put out 12.X volts even running. That's what mine does when the starting battery is fully charged. 13.x right after starting. I set the cut off at 12VDC even. The Victron will step up the voltage to the 13.5 bulk charge no matter what the incoming voltage is.
I guess you can use those chargers with solar and set them down to 11 VDC or so before it stops charging.

[booster]

Originally Posted by Richard Cranium

I just put a victron on my 2006 Road Trek. You can configure when the charger shuts off in the app. Some alternators only put out 12.X volts even running. That's what mine does when the starting battery is fully charged. 13.x right after starting. I set the cut off at 12VDC even. The Victron will step up the voltage to the 13.5 bulk charge no matter what the incoming voltage is.
I guess you can use those chargers with solar and set them down to 11 VDC or so before it stops charging.

What is the rest of the system to go with the Orion B to B? One alternator, I assume?