Adverc in a 'hybrid' setup?

[Richardcn]

Morning All

 

We're currently considering the switch to a Lithium 'house battery' but in all my researching, here and elsewhere, I can't find much concerning how an existing Adverc might fit in so I thought I'd ask you ladies & gentlemen for your thoughts.

 

Our current arrangement is lead acid/lead acid, a RN DM2 with, I think (still to be tested) a 65a alternator (Lucas LRA 406) & Adverc charge controller, 40a Epever mppt with excess solar and a Victron 30a charger.

 

My current thoughts are to install a Fogstar 280 or 300, retain the LA starter with a B2B in-between. My question is would it be okay (or even maybe a good idea) to switch the Adverc over to the starter battery or is this going to cause problems? I do still have to check the output of the alternator with the Adverc disconnect as I have some concern that it might be sub 14v!

 

I look forward to your replies.

 

Regards

Richard

 

 

[Tony Brooks]

9 minutes ago, Richardcn said:

Morning All

 

We're currently considering the switch to a Lithium 'house battery' but in all my researching, here and elsewhere, I can't find much concerning how an existing Adverc might fit in so I thought I'd ask you ladies & gentlemen for your thoughts.

 

Our current arrangement is lead acid/lead acid, a RN DM2 with, I think (still to be tested) a 65a alternator (Lucas LRA 406) & Adverc charge controller, 40a Epever mppt with excess solar and a Victron 30a charger.

 

My current thoughts are to install a Fogstar 280 or 300, retain the LA starter with a B2B in-between. My question is would it be okay (or even maybe a good idea) to switch the Adverc over to the starter battery or is this going to cause problems? I do still have to check the output of the alternator with the Adverc disconnect as I have some concern that it might be sub 14v!

 

 

As long as you can program the B2B output to the lithiums then I would think that having the Adverc charging the engine battery would not cause any problems, but as start batteries spend all the time more or less fully charged I suspect that even with a 13.8 to 14.2V alternator regulator it would still keep the start battery well charged without the Adverc.

 

All the Adverc does is boost the charging voltage, so the extra voltage can push more current into the battery, so providing the B2B can supply a reduced charging volatge to the Lithinums as required using the Adverc should be fine.

[Richardcn]

Marvelous, thanks.That's how I saw it but it's always worth checking I believe. 

 

Re the alternator, I'm intending to do two tests by switching on our 1kw immersion once the engine is warmed up:

1) Volts & Amps output - With Adverc

2) Ditto - Without Adverc

I just want to get a full understanding of this aspect of our charging system prior to ordering a B2B & Fogstar Lithium. We only usually run the engine whilst cruising so I'd rather be conservative with the B2B. 

Is there anything else worth checking in regards to the Alt? 

 

Richard

 

 

Edited September 3 by Richardcn

[dmr]

I can see very little point in keeping the Adverc, its purpose in life was increasing the voltage to the domestic bank. The voltage should already be fine for the starter battery and the B2B should sort out the voltage at the domestics and should (hopefully) control the voltage at the starter to keep the alternator working hard.  Internal alternator regulators do reduce alternator output too quickly but I am moderately confident that a good B2B will avoid this.

A bit of experimentation is required.

The Adverc was a fine device, it served me well for 15 years, but its now old technology.

I assume that you will be using the new version of the Victron Orion DC charger???

[nicknorman]

The adverc changes the voltage/current profile of the alternator during charge, ie at mid to high states of charge when the battery voltage has risen a bit, the alternator will output more current for a given voltage. However if you are using a B2B to charge the Li, I don’t think it will make any difference to that, because, depending on the spec of the actual B2B, the B2B will be able to pull the alternator voltage low enough to get max output (or whatever the B2B is rated at). However it might result in the voltage to the starter battery being rather low and the adverc might help with this. 
 

Some other things to consider are avoiding overheating the alternator - either make sure the B2B is rated no more than about 60 to 70% of the alternator rating, or if the Adverc has an alternator temperature sensor use that to reduce alternator output to avoid overheating it.

 

You also need a mechanism to control the B2B. Simplistically this might be just the source battery voltage, but I would include a means to manually disable the B2B for summer days when the Li is already well charged and you want to go for a long cruise. Li batteries don’t like to be fully charged every day, nor held at high charge voltage once they are full (although the Fogstar BMS will help with this). Most B2B have some sort of input that allows them to be switched on and off.

 

In my caravan I use a BMV712 in the Fogstar circuit, and I use the BMV712 relay output to control the solar so it will automatically stop charging at around 85% or whatever I set in the BMV configuration app.

Edited September 3 by nicknorman

[dmr]

2 minutes ago, nicknorman said:

The adverc changes the voltage/current profile of the alternator during charge, ie at mid to high states of charge when the battery voltage has risen a bit, the alternator will output more current for a given voltage. However if you are using a B2B to charge the Li, I don’t think it will make any difference to that, because, depending on the spec of the actual B2B, the B2B will be able to pull the alternator voltage low enough to get max output (or whatever the B2B is rated at). However it might result in the voltage to the starter battery being rather low and the adverc might help with this. 
 

Some other things to consider are avoiding overheating the alternator - either make sure the B2B is rated no more than about 60 to 70% of the alternator rating, or if the Adverc has an alternator temperature sensor use that to reduce alternator output to avoid overheating it.

 

You also need a mechanism to control the B2B. Simplistically this might be just the source battery voltage, but I would include a means to manually disable the B2B for summer days when the Li is already well charged and you want to go for a long cruise. Li batteries don’t like to be fully charged every day, nor held at high charge voltage once they are full (although the Fogstar BMS will help with this). Most B2B have some sort of input that allows them to be switched on and off.

 

In my caravan I use a BMV712 in the Fogstar circuit, and I use the BMV712 relay output to control the solar so it will automatically stop charging at around 85% or whatever I set in the BMV configuration app.

 

The newer Victron B2B is dead clever and has a selectable current limit so it should be possible to use this to avoid over heating the alternator. I believe it will also modulate the charge current to maintain a (selectable) voltage at the starter battery. And it does have an "allow to charge" input.

Ive got one here but have not fitted it yet, maybe next week 😀

[Tony Brooks]

1 hour ago, Richardcn said:

Marvelous, thanks.That's how I saw it but it's always worth checking I believe. 

 

Re the alternator, I'm intending to do two tests by switching on our 1kw immersion once the engine is warmed up:

1) Volts & Amps output - With Adverc

2) Ditto - Without Adverc

I just want to get a full understanding of this aspect of our charging system prior to ordering a B2B & Fogstar Lithium. We only usually run the engine whilst cruising so I'd rather be conservative with the B2B. 

Is there anything else worth checking in regards to the Alt? 

 

Richard

 

 

 

Last question - yes brushes, it must be fairy old.

 

Now the testing part. You may get odd results because of the way alternator voltage reacts to charging currant - as Nick has alluded to.

 

Basically, the higher the charging current, the lower the charging voltage until such time as the currant has fallen enough for the voltage to rise enough to allow the regulator to start working. So with the B2B presenting what looks like a fairly flat battery to the alternator, you may find that you do not even get to the regulated voltage because of the high current demand. If that is the case, and I suspect it will be, then as DMR say the Adverc will just sit there and do nothing.

 

When the BMS disconnects the charge from the lithiums then I expect the charging voltage to rise so the Adverc can up the charging voltage to push a bit more into the battery, so charging an already well charged battery slightly faster. If this has a practical advantage, I would not like to say.

 

 

 

Edited September 3 by Tony Brooks

[dmr]

If I am wrong and the Adverc does increase the current into the lithiums then there is a potential problem in that the Adverc cycles the voltage up and down (in an attempt to reduce water loss) and also has a long rest period after a few hours of working.  Depending on your cruising pattern and battery use, and hence the need to get maximum charge into the batteries quickly, this could be a limitation, but lets face this one if it turns out that the Adverc is increasing charge current.

[nicknorman]

2 minutes ago, dmr said:

If I am wrong and the Adverc does increase the current into the lithiums then there is a potential problem in that the Adverc cycles the voltage up and down (in an attempt to reduce water loss) and also has a long rest period after a few hours of working.  Depending on your cruising pattern and battery use, and hence the need to get maximum charge into the batteries quickly, this could be a limitation, but lets face this one if it turns out that the Adverc is increasing charge current.

I would have thought the B2B didn’t particularly care if the input voltage was 14v or 14.4v (or whatever the cycling voltages are). But, depending on the ratio of B2B current to alternator rating, it might well be that the alternator voltage never gets that high whilst the B2B is on.

[Tony Brooks]

5 minutes ago, dmr said:

If I am wrong and the Adverc does increase the current into the lithiums then there is a potential problem in that the Adverc cycles the voltage up and down (in an attempt to reduce water loss) and also has a long rest period after a few hours of working.  Depending on your cruising pattern and battery use, and hence the need to get maximum charge into the batteries quickly, this could be a limitation, but lets face this one if it turns out that the Adverc is increasing charge current.

 

I don't see how the Adverc can increase the current into the lithiums because  the B2B is between them and that should be capable of limiting the current to stop overheating the alternator.

FWIW: I just looked LRA406 up, and it seems to be what we tend to call a Lucas A127. If the regulated voltage is low, then I am sure a new regulator will fix that. However, I would try it as it is first before doing much more. 

[dmr]

My observation is that some (many/most?) alternators go into absorption mode much too quickly due to the design of the voltage control system in the regulator. So, an alternator regulated at 14.6 volts will not be providing full field drive right up to 14.6 but will start progressively reducing the drive at a much lower votage. So the unknown here is will the B2B load up the alternator enough to drop its voltage to a level where it provides full field drive, and my guess is that it will.

[Richardcn]

Many thanks for your advice so far, unfortunately my grandson requires me to build a space rocket out of stickle bricks at the moment so my replies will be somewhat delayed due to the enormity of the task ahead! 😆

3 hours ago, dmr said:

 

I assume that you will be using the new version of the Victron Orion DC charger???

I've yet to look closely at these until I've determined the alternator output capacity.

[BEngo]

1 hour ago, Richardcn said:

grandson requires me to build a space rocket out of stickle bricks

Check carefully that any or all helium tanks are not leaking.  Ensure you fit extra  spare thrusters.  Beware of strange noises in the pointy bit.

 

N

[Richardcn]

21 minutes ago, BEngo said:

Check carefully that any or all helium tanks are not leaking.  Ensure you fit extra  spare thrusters.  Beware of strange noises in the pointy bit.

 

N

Naturally! 

 

Getting stickle brick structures symmetrical is a right pain in the neck though, I prefer Lego. However he's only (almost) 3 and these are easier for him to learn the basics of building things and who knows where it will lead? Having a dad who's currently a fab/welder and previously a car mech may well seal his fate though 😆

[dmr]

Enjoy the Stickle bricks while you can, and they were good things to play with, but it will soon be Duplo, then Lego, then Lego technic, and from about 9 onwards you can get then doing a bit of real bricklaying.

[Richardcn]

5 hours ago, nicknorman said:

You also need a mechanism to control the B2B. Simplistically this might be just the source battery voltage, but I would include a means to manually disable the B2B for summer days when the Li is already well charged and you want to go for a long cruise. Li batteries don’t like to be fully charged every day, nor held at high charge voltage once they are full (although the Fogstar BMS will help with this). Most B2B have some sort of input that allows them to be switched on and off.

 

Useful to know thanks, I hadn't considered that.

[Tony Brooks]

29 minutes ago, dmr said:

Enjoy the Stickle bricks while you can, and they were good things to play with, but it will soon be Duplo, then Lego, then Lego technic, and from about 9 onwards you can get then doing a bit of real bricklaying.

 

My brother, back in the day, was given a very expensive building kit consisting of tiny bricks, window frames and doors. You used cold water starch based paste for cement and when you demolished the building you just soaked the paste off the bricks. Never seen one before or since.

[Richardcn]

31 minutes ago, dmr said:

Enjoy the Stickle bricks while you can, and they were good things to play with, but it will soon be Duplo, then Lego, then Lego technic, and from about 9 onwards you can get then doing a bit of real bricklaying.

Bring it on! (Again)

[dmr]

1 minute ago, Tony Brooks said:

 

My brother, back in the day, was given a very expensive building kit consisting of tiny bricks, window frames and doors. You used cold water starch based paste for cement and when you demolished the building you just soaked the paste off the bricks. Never seen one before or since.

 

Yes, my children had this plus the extension kit, I think it was German. Another one of the things that we sold cheaply when we moved onto the boat, and now wish we had kept.

[Richardcn]

5 hours ago, dmr said:

 

The newer Victron B2B is dead clever and has a selectable current limit so it should be possible to use this to avoid over heating the alternator. I believe it will also modulate the charge current to maintain a (selectable) voltage at the starter battery. And it does have an "allow to charge" input.

Ive got one here but have not fitted it yet, maybe next week 😀

This sounds interesting. I'm sure I saw a B2B in the last couple of weeks that would reverse charge (house to starter) as required as well?

[dmr]

....

They still exist, loads on Amazon and eBay.

Never as much fun as Lego though.

[Richardcn]

5 hours ago, Tony Brooks said:

 

Last question - yes brushes, it must be fairy old.

 

Now the testing part. You may get odd results because of the way alternator voltage reacts to charging currant - as Nick has alluded to.

 

 

 

 

 

Yes I should probably take a look at the brushes and I'll be prepared for potentially "... odd results..."

5 hours ago, dmr said:

If I am wrong and the Adverc does increase the current into the lithiums then there is a potential problem in that the Adverc cycles the voltage up and down (in an attempt to reduce water loss) and also has a long rest period after a few hours of working.  Depending on your cruising pattern and battery use, and hence the need to get maximum charge into the batteries quickly, this could be a limitation, but lets face this one if it turns out that the Adverc is increasing charge current.

Yes I'll need to keep a close eye on things for a while if I do retain the Adverc until I've used the new setup in all the likely different operating modes.

5 hours ago, Tony Brooks said:

FWIW: I just looked LRA406 up, and it seems to be what we tend to call a Lucas A127. If the regulated voltage is low, then I am sure a new regulator will fix that. However, I would try it as it is first before doing much more. 

Yes or maybe an A133? I have wondered if that is the reason why the Adverc was fitted in the first place.

[dmr]

20 minutes ago, Richardcn said:

This sounds interesting. I'm sure I saw a B2B in the last couple of weeks that would reverse charge (house to starter) as required as well?

 

There was a rumour (on this forum?) that the new Victron (Orion XS) would be able to do this but when it arrived it was not able to. I think somebody said this might happen in the future via a software update

[Richardcn]

5 hours ago, dmr said:

So the unknown here is will the B2B load up the alternator enough to drop its voltage to a level where it provides full field drive, and my guess is that it will.

I'm hoping so and maybe the Adverc might help in that respect?

[PeterF]

17 minutes ago, dmr said:

 

There was a rumour (on this forum?) that the new Victron (Orion XS) would be able to do this but when it arrived it was not able to. I think somebody said this might happen in the future via a software update

Yes, the hardware will support bi-directional charging but the firmware does not as of the date of posting. Victron are being coy about if / when this will be implemented saying they have more important things to sort out first.