Is this a problem?

[U.Toadifact]

We recently bit the bullet and had Vanbitz install a full lithium set up with DC to DC, Battery Master and new mains charger. Since then I have noticed that the DC to DC charger kicks in when the van is on EHU. Once the EHU is disconnected, the DC to DC shuts down shortly afterwards. Obviously the engine is not running.

I believe Vanbitz installed the systen with connecting the DC to DC to a D+ signal as shut down detection is on. Is this behaviour harmful in any way or can I safely ignore it?

 

[frwjd]

I believe that is correct but surely Vanbitz are the people to ask

 

[U.Toadifact]

Thnk you for your reply. I believe Ash is on holiday at present.

 

[AdrianChen]

Which DC to DC charger have you got - mine is Victron - the D+ is connected to the H terminal, and the engine shutdown detection is off/disabled.

At the same time the link/jumper wire in the small green or grey plug should have been removed.

The DC to DC will be sending more current back to the leisure battery than the BM can send to the starter, so you may find the starter battery gets low....

 

[U.Toadifact]

It is a Victron Orion SX.

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[AdrianChen]

I suspect when the EHU charger is on, and the start battery is full the BM is just able to raise the start battery voltage enough to trigger the orion - but with D+ connected to the H terminal (jumper removed) you shouldnt need engine shutdown detection...

 

[U.Toadifact]

Thanks Adrian. I am 95% certain there is no connection from the D+. I will take a look later.

 

[gilbaro]

I checked with Ash recently and apparently that is what should happen

 

[Pausim]

I would have thought it would be better to have a D+ connection and turn off the shut down detection. Having the B2B come on with an EHU connection sounds wrong to me. The Orion XS manual is poorly written, Offgrid Power Solutions did a short video saying how to set up the XS and pointing out how misleading the manual can be on this point.

 

[Bill-H]

If the B to B doesn't have a D+ signal to activate it but relies on detecting a higher voltage to the engine battery (i.e. engine and alternator running) to start it operating, I'd guess that being on EHU starts the engine battery charging - which ups the volts to it and kicks in the B to B
My Renogy B to B needs no D+ signal but activated when it detects a higher voltage to engine battery

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[AdrianChen]

If the B to B doesn't have a D+ signal to activate it but relies on detecting a higher voltage to the engine battery (i.e. engine and alternator running) to start it operating, I'd guess that being on EHU starts the engine battery charging - which ups the volts to it and kicks in the B to B
My Renogy B to B needs no D+ signal but activated when it detects a higher voltage to engine battery

Yes you could just put a higher voltage into the Orions settings for the engine shutdown detection, but on my van there was a d+ very close by, and it seemed the more reliable method......

 

[Bill-H]

Yes you could just put a higher voltage into the Orions settings for the engine shutdown detection, but on my van there was a d+ very close by, and it seemed the more reliable method......

From a little I read when installing a B to B in a friend's camper, older 'non-smart' alternators put out a higher voltage than later smart ones, the later ones a more likely to need a D+ connection to activate them because of this.
I didn't add any external monitoring/ system setting so had no way to adjust it.
I agree that D+ would be a more reliable option if available

 

[LithiumConvert]

Surely, the answer to this is to only fit a quality B2B on which the D+ signal is the only way of activating the charger (when set to work that way).

Searching these forums will highlight some makes (one in particular) which, simply, do not work correctly.

And, if having work done, to ask what make of any (and all) equipment will be used.

 

[Pausim]

Surely, the answer to this is to only fit a quality B2B on which the D+ signal is the only way of activating the charger (when set to work that way).

Searching these forums will highlight some makes (one in particular) which, simply, do not work correctly.

And, if having work done, to ask what make of any (and all) equipment will be used.

U.Toadifact has a top quality B2B with D+ operation. Turning off the alternative detection is very easy and providing a D+ signal is not usually difficult.

 

[yorkiebar]

I wouldn't be happy with the Orion XS kicking in when on EHU. If configured to 50A output power then that's going to drain your starter battery down to the lower voltage threshold pretty quickly. As others have mentioned, a D+ trigger is the way to go,

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[U.Toadifact]

Thanks for all the replies. When the Orion kicks in on hook up, there is no noticeable drain on the starter battery, possibly because the mains charger is charging that too.

 

[Gromett]

I wouldn't be happy with the Orion XS kicking in when on EHU. If configured to 50A output power then that's going to drain your starter battery down to the lower voltage threshold pretty quickly. As others have mentioned, a D+ trigger is the way to go,

If it starts to lower the voltage then the orion would then cut out again? I cannot see how the orion would discharge the starter battery fully?

 

[yorkiebar]

If it starts to lower the voltage then the orion would then cut out again? I cannot see how the orion would discharge the starter battery fully?

It shouldn't, but I'd prefer to have the D+ signal determine when the B2B starts/stops.

 

[LithiumConvert]

[The OP] has a top quality B2B with D+ operation.

Not the way I read these and other posts.

But, we all have our preferences.

 

[AdrianChen]

If it starts to lower the voltage then the orion would then cut out again? I cannot see how the orion would discharge the starter battery fully?

Easy to check on the trends part of the app.

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[yorkiebar]

Not the way I read these and other posts.

But, we all have our preferences.

It is confusing, the OP initially stated that they thought the B2B had a D+ signal but later posted they were 95% sure it didn't have D+.
From the behavior described it sounds like there isn't a correctly installed D+ signal triggering the B2B. That could be D+ missing entirely or the green "jumper" left in place between H & L terminals on the B2B, wasn't there another poster recently with that left in place ?

 

[U.Toadifact]

Sincere apologies. My OP suffered from fat finger syndrome. The line in question should read "installed without a D+ signal."

 

[Pausim]

Not the way I read these and other posts.

But, we all have our preferences.

If the Orion XS has a fault it is that it can be configured in a number of different ways which leaves it open to be wrongly installed or set up poorly. On the other hand those features also make it a very flexible unit and it has the usual Victron quality. The simplest set up is to connect the D+ and turn the engine sensing algorithm off. I had a Votronic B2B previously, another excellent unit but very large compared to the XS.

 

[ChrisL]

I have a 30amp Victron B2B which is setup to use voltage sensing, it does open sometimes when the starter battery voltage is high enough but does turn itself off when it drops to 12.8 volts its never flattened the starter battery, as I write the B2B is closed and the starter battery is at 13.05 volts it will open again if the starter battery gets to 13.2 volts.

 

[AdrianChen]

Sincere apologies. My OP suffered from fat finger syndrome. The line in question should read "installed without a D+ signal."

OK well if there is no D+ then you need engine detection on of course, and the small jumper should be in the H/L plug.

Is the Battery Master wired directly into the Orion XS terminals?

Easiest thing to do while you are away is just switch the Orion off in the battery settings.

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[Pausim]

U.Toadifact I wonder how difficult it would be for you to find a D+ signal and wire the B2B to operate reliably. All the motorhomes I have had in the last 10 years have had an easily accessible D+ signal from the 12V distribution unit (2 Schaudt EBLs and 1 CBE DS). In my opinion voltage sensing is very much a second best. You really only want the B2B to turn on when the engine is running. Voltage sensing sometimes seems to turn a B2B on when other devices such as mains chargers, solar, battery maintainers etc. are involved.

I don’t really know what is happening in your system but this is my guess. You pull up and turn the engine off and the B2B switches off as it should. You plug in to an EHU and the mains charger raises the voltage in your leisure battery. This in turn switches on the Battery Master and possibly the mains charger is also supplying a trickle charge to the engine battery. The B2B senses the higher engine battery voltage and switches on. You now have everything trying to charge everything else. IF this is what is happening it would not only be inefficient but would possibly mean that the devices don’t know when to switch between bulk charge and maintenance voltage. I am very open to someone telling me I am wrong because ………………… would stop this happening. However I would be very unhappy if my B2B switched on at any other time than when the engine was running.

Slightly off the original subject I have 2 B2Bs, the original Schaudt/Lippert WA121525 and the better Victron Orion XS 50. I noticed that the Orion was switching off the bulk charge as it should when the battery was full but the voltage was not dropping because the less sophisticated Schaudt unit was still pushing out the higher voltage. I adopted the Lenny HB advice of putting a switch on the Schaudt D+ and all is now operating as it should. I can still run both B2Bs in parallel when I need a big charge but mention this as an example of what can happen when more than one device is operating at the same time.

 

[Lenny HB]

Sincere apologies. My OP suffered from fat finger syndrome. The line in question should read "installed without a D+ signal."

Surprised any installer would install it like that these days.
The Orion XS is a top bit of kit but the installer does need to know what he is doing.

 

[LithiumConvert]

All the motorhomes I have had in the last 10 years have had an easily accessible D+ signal from the 12V distribution unit

However, new Hymers and Carthagos (and others) go one better and are now factory fitted with a D+ activated B2B whiich means changing to LiFePO4 really is getting much easier. Just change some DIP switches.

Yes, I know LennyHB and others have reservations about the chargers fitted, but in my 2 year experience with them, it really has been Plug and Play.

 

[U.Toadifact]

Thanks again for the replies. I am no electrical genius so I am reluctant to start messing with a professionally installed set up.

I have been in touch with Vanbitz who have asked me to send them screen shots of the relevant app pages which I will do next week. I just hope they don't want me to take the van back as it is a real schlepp from Toadifact Towers.

If no harm is being done, for the few times I will need ehu in future I am tempted to live with it.