DC Battery Rig

[mtompson]

Just updating the text for the Victron battery monitor, as they have new models out.

[botanybay]

Originally Posted by mtompson

Just updating the text for the Victron battery monitor, as they have new models out.

I am running the new 702 and it is a wonderful unit.

I am using the midpoint monitoring function rather than temperature.

The cable between the shunt is an rj12 6x6 twist cable (I.e. pin one goes to pin one on the other end) which is rather long. I replaced it with a 1 foot cable.

I also demoted the shunt circuit board a few inches away with #16 twisted pair for a clean install in my case.

The percent imbalance in the midpoint monitoring is a nice feature.

Now to the fun of integrating two monitors into one color control gx display!

[mtompson]

Thanks botanybay!

Here is a new schematic, not many big changes, just little tweaks.

[mtompson]

This panel from Bluesea fits the bill!

[goboatingnow]

you show a switch on the alternator feed , whats that about?

dave

[Maine Sail]

Originally Posted by goboatingnow

you show a switch on the alternator feed , whats that about?

dave

Service disconnect switch most likely. When the alt is direct wired to the house bank guys like me appreciate a service disconnect switch in the engine bay so the alt B+ is not live.....

[mtompson]

Yes, just a safety thing to isolate the engine when you work on it, as the alternator feed goes directly to the battery and not through any of the main switches.

You could argue the need for more on any of the charge inputs? Maybe it depends what they are coming through on the way (regulator)

[FlyingCloud1937]

YEP,

Anything connected direct to Battery/Bus, should have a service disconnect.

Sometimes it's just a simple fuse pull.

But a service disconnect is in order, if it takes tools to pull the fuse.

Llloyd

Originally Posted by Maine Sail

Service disconnect switch most likely. When the alt is direct wired to the house bank guys like me appreciate a service disconnect switch in the engine bay so the alt B+ is not live.....

[mtompson]

Yes those battery terminal fuses for example would be a pain to keep 'pulling'!

[mtompson]

Ok, any thoughts on simply using a Blue Sea dual circuit system switch instead of my suggested 3?

[RainDog]

Originally Posted by mtompson

Ok, any thoughts on simply using a Blue Sea dual circuit system switch instead of my suggested 3?

That is addressed earlier in the thread. Posts #20, #55, and #56.

[mtompson]

Thanks RainDog, I really should read more carefully. ( my excuse, I'm always too tired )

[Auger01]

I would put your "on-off" switches for the batteries between the main battery fuse and the buss bars and put the bilge pump to the house battery and put the alternator to the buss bar.

The way you have it drawn now if your house bank dies, sure you can start the engine, but you aren't going very far. Unless the engine runs on a magneto, its needs power to run plus whatever else you leave on will drain the start battery fairly rapidly.

If you put the alternator on the buss bar after the battery switch, whenever you use your emergency switch, the start battery will get charged by the alternator and/or solar. The only disadvantage of doing it that way is that you need to make sure the either the house or the emergency switch is "on" otherwise the alternator output wont be connected to a battery, which could cause damage to the alternator or other equipment.

Have you considered the ML series ACR from blue sea? It would simplify your wiring because it handles the function of the emergency switch as well as the acr functions. It also has manual control and yes, you can physically lock it open. It retails for about 170 bucks.

https://www.bluesea.com/products/762..._-_12V_DC_500A

[mtompson]

Thanks Auger01 ( sorry for late reply! ) the way I see it, even with the house switch off, the charge sources inc alternator will go through the echo as normal? I'm not sure if a dead house battery will upset the echo bridge over to the aux battery?

[Ex-Calif]

Originally Posted by Auger01

I would put your "on-off" switches for the batteries between the main battery fuse and the buss bars and put the bilge pump to the house battery and put the alternator to the buss bar.

The way you have it drawn now if your house bank dies, sure you can start the engine, but you aren't going very far. Unless the engine runs on a magneto, its needs power to run plus whatever else you leave on will drain the start battery fairly rapidly.

If you put the alternator on the buss bar after the battery switch, whenever you use your emergency switch, the start battery will get charged by the alternator and/or solar. The only disadvantage of doing it that way is that you need to make sure the either the house or the emergency switch is "on" otherwise the alternator output wont be connected to a battery, which could cause damage to the alternator or other equipment.

<snip>

I know this thread is getting old and the system is probably locked down already but that's what has been bugging me as well.

I like the "engine" stuff on one side and the "house" stuff on the other. Presumably to start the engine you are gonna need some sort of battery connected. The attached schematic puts the alternator on the engine side and presuming someone turned on a battery you can't fry the alternator.

The switches are marked "House" and "Engine" - To me this intuitively indicates what 'system" I am supplying.

The 1 and 2 posts of each switch indicate what you are supplying "from" Bank 1 or Bank 2, House or Engine and I would label them "House Bank" and "Engine Bank"

1-2-All switches give you complete flexibility on which bank supplies which system.

The ACR won't parallel if either bank is failed (low voltage or high voltage) so it's a matter of isolating the banks with the two switches. Want to run the whole boat on House Bank or Start Bank? Easy peasy.

The windlass can run heavy gauge, taking advantage of engine on via ACR (e.g. Engine switch left in Engine Bank) or can run off an echo charger from the distribution bus for anyone who wants that.

The only caveat here is that for any non-engine charging to occur the house has to be in at least the House Bank position. If it is not clear the "normal" position is -

- House switch to House Bank
- Engine switch to Engine Bank

If you wanted to make the boat dark and leave it but wanted a battery maintainer, maybe you add a maintainer solar panel directly to the house bank.

I'd be happy to hear what's wrong with my schematic - Always learning.

Originally Posted by mtompson

Thanks Auger01 ( sorry for late reply! ) the way I see it, even with the house switch off, the charge sources inc alternator will go through the echo as normal? I'm not sure if a dead house battery will upset the echo bridge over to the aux battery?

The way you are wired - if the house fails you switch it off to isolate it. However all your charge sources are still trying to fill a dead bank - it could be dead shorted for all we know. I think you will have bad results.