Installing a VSR specifically for solar panels

[stormalong]

Originally Posted by coopec43

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

Once again you are demonstrating your lack of knowledge of electrical systems. Yes, I know you are offended by the truth.

The VSR joins the two batteries anytime the voltage of either battery rises to a predetermined voltage that indicates that it is being charged FROM ANY SOURCE. It does not matter if it is solar, wind, alternator or hand crank generator. ANY SOURCE

[Wotname]

Originally Posted by coopec43

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

OK, Standby for amended flow chart but regardless, you already have everything you need.

[Wotname]

Amended flowchart.

If you want the alternator going direct to the house battery first, that's your choice.

I prefer it going to the start battery first as that way, the alternator tops up the start battery immediately after a start. It only takes a few minutes to replenish a start battery after a normal start. It is then connected to the VSR to charge the house battery.

If the alternator goes to the house battery first, the house battery has to reach near full charge before the VSR connects the alternator to the start battery. That could take an hour or so depending on the state of charge in the house battery.

Regardless, if the boat is unattended, the solar will first fully charge the house and then be connected via the VSR to the start battery.

[Wotname]

And before you ask - no, having the alternator output connected to the output of the MPPT controller will not cause any charging problems.

[sailingharry]

Originally Posted by Wotname

Amended flowchart.



If you want the alternator going direct to the house battery first, that's your choice.



I prefer it going to the start battery first as that way, the alternator tops up the start battery immediately after a start. It only takes a few minutes to replenish a start battery after a normal start. It is then connected to the VSR to charge the house battery.



If the alternator goes to the house battery first, the house battery has to reach near full charge before the VSR connects the alternator to the start battery. That could take an hour or so depending on the state of charge in the house battery.



Regardless, if the boat is unattended, the solar will first fully charge the house and then be connected via the VSR to the start battery.

Wot's comments on sending the alternator to the start battery then through the VSR to the house battery is a reasonable opinion shared by many. This prioritizes charging the start batter.y.

As in many things, there is the other position, also shared by many. Lol.

The way you intend, going first to the house then through the VSR to the start, prioritizes charging the house bank, which is normally the bank most in need of attention. It has the other advantage of not sending the heavy house charge current through the VSR. Large charge sources, such as my boat where the combined alternators can easily supply over 200A, can exceed the capacity of many VSRs.

Either is a reasonable and defensible position. Read the pros and cons, make a decision, and know that the difference between the two choices is more of a nuance than a crisis.

[coopec43]

Originally Posted by sailingharry

Wot's comments on sending the alternator to the start battery then through the VSR to the house battery is a reasonable opinion shared by many. This prioritizes charging the start batter.y.

As in many things, there is the other position, also shared by many. Lol.

The way you intend, going first to the house then through the VSR to the start, prioritizes charging the house bank, which is normally the bank most in need of attention. It has the other advantage of not sending the heavy house charge current through the VSR. Large charge sources, such as my boat where the combined alternators can easily supply over 200A, can exceed the capacity of many VSRs.

Either is a reasonable and defensible position. Read the pros and cons, make a decision, and know that the difference between the two choices is more of a nuance than a crisis.

Thanks for that, I can understand what you are saying.

But neither of you would know that when it comes to using "jumper leads" I am an absolute expert (I would never leave home without a H/D set in the boot of my car).

Yes I do read the pros and cons on these threads which I find incredibly useful (What did boat builders do before the advent of online forums?)

[Wotname]

Regarding 'jumper leads', don't forget to wire up the 'start assist' function of the Cyrix VSR.

This turns your VSR into "a set of jumper leads" for 30 seconds at the push of a small button switch i.e. it connects the house battery directly to the start battery for 30 seconds regardless of the voltages present on each battery.

[coopec43]

Originally Posted by Wotname

Regarding 'jumper leads', don't forget to wire up the 'start assist' function of the Cyrix VSR.

This turns your VSR into "a set of jumper leads" for 30 seconds at the push of a small button switch i.e. it connects the house battery directly to the start battery for 30 seconds regardless of the voltages present on each battery.

Thanks Wotname.

Right now I'm reading up on VSRs but I've yet to come to an explanation of that feature in the article.

https://www.12voltplanet.co.uk/user/...structions.pdf

Maybe I'll have to look at a video as well.

https://www.youtube.com/watch?v=dwcl3rdlq98

[Wotname]

Pro tip - go to the manufacturers website for technical information about any individual products rather than the aftermarket guys. Sure, get a basic understanding from the YT fellas but then confirm what you have learnt by going to the manufacturer of the product, especially when it comes to connecting the wires.

Victron has an excellent knowledge base on their site and also some good 'how to' videos.

So for your Victron Cyrix, go to https://www.victronenergy.com/batter...ers#datasheets
Read the data sheet and manual and peruse the other links there.

Every Victron product has a wealth of info on the Victron site.

Note - Start assist is a term used Victron, other manufacturers either don't offer the option or if they do, it will have a another name like say 'emergency parallel' or some such.

[MVDarlin]

Be careful of hiw you describe 1# and #2. On both my boats #1 is the house bank!

[MJH]

Originally Posted by coopec43

When I installed the inverter I thought I'd be smart and use a 1/2/both switch so I had flexibility as to where I drew the input power from (House or Starting bank)

That resulted in a a molten negative cable and one of the starting batteries destroyed. I have removed the 1/2/both switch and now plan to charge both battery banks using the alternator and a Victron Cyrix 24V VSR.

Now I am considering using an additional VSR purely for the solar panels. The VSR I am considering is quite reasonably priced and has more than enough capacity. Is that a crazy idea?

I don't see a need for a VSR (Voltage Sensitive Relay).

I have 4 x 140W (560W total) solar panels, two above the dodger and two on a stern arch. Each has its own controller and each pair connects to one of the two house 8D batteries. There is a starting battery bank as well. Between the two banks is an Automatic Charging Relay (Blue Sea Systems #7650) that keeps them charged...I never have to worry about them. I do keep things managed with a Xantrex LinkPro Battery Monitor. I have never had a problem with this setup.

KISS (Keep It Simple Stupid) is always best...no offense intended.

[smac999]

Originally Posted by MJH

I don't see a need for a VSR (Voltage Sensitive Relay).

I have 4 x 140W (560W total) solar panels, two above the dodger and two on a stern arch. Each has its own controller and each pair connects to one of the two house 8D batteries. There is a starting battery bank as well. Between the two banks is an Automatic Charging Relay (Blue Sea Systems #7650) that keeps them charged...I never have to worry about them. I do keep things managed with a Xantrex LinkPro Battery Monitor. I have never had a problem with this setup.

KISS (Keep It Simple Stupid) is always best...no offense intended.

A vsr and acr is the same thing by different brands.

So you just told him you have one and it works great but he doesn’t need one?

[MJH]

Originally Posted by smac999

A vsr and acr is the same thing by different brands.

So you just told him you have one and it works great but he doesn’t need one?

He doesn't need ANOTHER one.

[coopec43]

Originally Posted by smac999

A vsr and acr is the same thing by different brands.

So you just told him you have one and it works great but he doesn’t need one?

Thanks smac, MJH (and others).

I think it time I sat down and digested this thread which I will do in the next few days

(It doesn't help when it seems Victron has a different name for electronic gadgets they manufacture -VSR = "Battery isolator" ("combiner")

[PaulCrawhorn]

Yes original name was "battery combiner" to distinguish from the previous inferior diode based "isolaters"

VSR and ACR are the same functionality, Blue Sea makes top notch units using the later label.

Voltage sense from either side is pretty standard.

No manual switching anymore is the main point, but overrides can be useful.