Installing a VSR specifically for solar panels

[coopec43]

Originally Posted by stormalong

That won't work for the OP. It is only for same voltage batteries. OP has 24v house bank and 12V engine start battery. That is something that the OP was not clear on in the beginning of this thread.

Also, the OP won't listen to you about cheap components ending up costing more. Read the posts from the beginning.

The simple solution for the OP's immediate need is to remove the engine start battery and move it to where it can be trickle charged until needed. If, as the OP states the boat is under construction he does not need to run the engine.

My House bank is 24V and my Starting Battery Bank is 24V.

Where have I said my Starting Bank was 12V? (I'm bewildered) (Apologies if I have but I don't know why I would)

(I need a Starting Bank to start the engine during different phases of construction)

[coopec43]

Originally Posted by jordanbigel

Hey, you do what you gotta do - and I get your problem is short term, so I think you can get away with using the inverter to power the charger, but, this is what I would install.

This guy is US$45 and is made to do what you want, it would be a great permanent addition to the boat even after construction is completed.

Victron Energy Orion-Tr 24/12-20 (240W) Isolated DC-DC converter

https://shop.pkys.com/Victron-Energy...er_p_8001.html

Thanks for that.

I've got a Victron MPPT controller for the solar. And I've got a Victron Cyrix VSR to handle the output of the alternator (I am using a VSR as the alternator is pre year 2000)

I will look at a "Victron Energy Orion-Tr 24/12-20 (240W) Isolated DC-DC converter" to split the solar charge.

I think we are getting there. Thanks!

[stormalong]

Originally Posted by coopec43

My House bank is 24V and my Starting Battery Bank is 24V.

Where have I said my Starting Bank was 12V? (I'm bewildered) (Apologies if I have but I don't know why I would)

(I need a Starting Bank to start the engine during different phases of construction)

Well then, it is completely dumb to run a 24 volt inverter to drive a battery charger to charge another 24 volt battery.

[coopec43]

Originally Posted by stormalong

Well then, it is completely dumb to run a 24 volt inverter to drive a battery charger to charge another 24 volt battery.

Geeez.......

[coopec43]

Time to move on? (I think we have flogged this one to death)

[PaulCrawhorn]

Ask a mod to close your thread.

And yes the land camping crowd has pathetic quality standards compared to what boats require

[smac999]

Originally Posted by coopec43

Thanks for that.

I've got a Victron MPPT controller for the solar. And I've got a Victron Cyrix VSR to handle the output of the alternator (I am using a VSR as the alternator is pre year 2000)

I will look at a "Victron Energy Orion-Tr 24/12-20 (240W) Isolated DC-DC converter" to split the solar charge.

I think we are getting there. Thanks!

you can't use both... they will mess each other up. pick one or the other.

if the alt goes to the engine battery and the solar goes to the house battery, and the batteries are the same type, then use the vsr.

if you wire the alt to the house bank and solar to house bank you could use either one.

[coopec43]

Originally Posted by smac999

you can't use both... they will mess each other up. pick one or the other.

if the alt goes to the engine battery and the solar goes to the house battery, and the batteries are the same type, then use the vsr.

if you wire the alt to the house bank and solar to house bank you could use either one.

Thanks smac.

What do you mean I "can't use both"?

I can't use a Victron MPPT controller IN CONJUNCTION WITH "Victron Energy Orion-Tr 24/12-20 (240W) Isolated DC-DC converter" to split the solar charge. Is that what you mean?

[smac999]

You can’t use the vsr and dc to dc. You’ll just get a current loop going between the 2 batteries.

[goboatingnow]

Originally Posted by smac999

You can’t use the vsr and dc to dc. You’ll just get a current loop going between the 2 batteries.

No you don’t unless they are setup wrong.

[coopec43]

Originally Posted by smac999

you can't use both... they will mess each other up. pick one or the other.

if the alt goes to the engine battery and the solar goes to the house battery, and the batteries are the same type, then use the vsr.

if you wire the alt to the house bank and solar to house bank you could use either one.

NO. I should have said the Alternator charge goes to the House Bank. Sorry!

[Wotname]

Coopec43, after reading this thread, I think you have everything you already need. As far as I can see, you have an alternator, Start battery, Victron Cyrix VSR, House battery, a Victron MPPT Solar controller and some solar panels.

All you have to do is connect them together as shown below.

I haven't determined if your alternator is internally or externally regulated but it should not matter in your case. I also haven't checked if the Cyrix VSR operates as a 'dual' or 'single' VSR but again it shouldn't matter too much. 'Dual' operation would be better but if it only operates as a 'single' it isn't a showstopper.

[Wotname]

I just checked and yes, the Cyrix senses the voltage of both batteries so it does work as a 'dual' VSR. I.E. it will direct the charge either way.

[Pete7]

Originally Posted by wingssail

Efficiency aside, how is this much different from a DC/DC charger?

The house battery is kept charged through other means, and the inverter, on the house battery, supplies AC to run the battery charger on the start battery.

It's not something I'd do but it sounds like it would work. I would not call it nonsense.

Particularly if the equipment like the inverter and charger are already on board. I get the sense this is a short term solution whilst on the hard and therefore not running the engine. Once finished and the engine is in regular use, there won't be any need.

Pete

[coopec43]

Originally Posted by Wotname

I just checked and yes, the Cyrix senses the voltage of both batteries so it does work as a 'dual' VSR. I.E. it will direct the charge either way.

Thanks for your comment.

As far as the "flowchart" above is concerned
the alternator charges the House Bank.

My understanding is the alternator charges the House Bank AND/OR the Starter Bank (As determined by the Cyrix VSR). In my set-up the Solar panels charge the House Bank only.

My worry is that if the yacht was left for an extended period the Starter Bank would go flat and result in damage. (The House Bank would be fine as it would be charged by the solar panels) I was thinking of using a VSR to split the solar charge between the House Bank and the Starter Bank but knowledgeable people have suggested a "DC DC Charger(?) which I plan to investigate.

Thanks for your interest