DC Battery Rig

[mtompson]

Ok, 1st stab at incorporating Maine Sail's Triple switch idea into the diagram...

[mtompson]

Oo just noticed I can change the name of the Aux bank to Start now! Will do it on the next update. The more I look at this rig, the more it grows on me as a solution.

Would you put the pos output ( to the house switch ) & the pos output from the batt, on the same post on the pos bus bar?

[ontherocks83]

Mainesail I have a question about another version of this diagram. What would your thoughts be if you add another 1/both/2/off switch between the house pos and the pos bus. Then connect both bank positives to the switch. The way I look at it you could isolate either bank if needed and if the house bank has an internal short you could switch all loads and the positive bus to the reserve battery.

[Hyprdrv]

MT you had asked what my setup was for the Starter Battery charging.
Well I have a little different setup than the rest of you guys, you see I'm an electric boat not an ICE driven one. My starter battery starts a 16KW Genset which can take a bit of draw. Since the Genset is actually my charging source rather than used to provide 120V service (I'm "rectified" out to 144V DC) I decided to "simplify" and let the Alternator (40A)charge only the Starter battery. It may not be the most efficiant use of the Alternator but after reading about all the hybrid Alts. with triple belts and gold plating I figured it would be less strain on the system and my wallet.
My Genset charges the Propulsion bank only. From there power is fed to a 144V to 12V charger that keeps the House bank topped. I have an Echo charger that hasn't been installed, my house batts are around 20' away from the start batt which was moved close to the Genset up front. The plan is to install solar panels this year to take the load off the Propulsion bank as much as possible.

Steve in Solomons MD

[mtompson]

Wow, that sounds great, I love the idea of a diesel electric setup one day, I'm not ready yet! I'll let you guys iron out all the R&D for a few more years!! :-)

[mtompson]

Latest schematic, if I want to monitor the start bank (nice to have!) is the wiring the same as on the house bank, or does the Echo or ACR have any weird effects?

[cal40john]

Originally Posted by mtompson

Latest schematic, if I want to monitor the start bank (nice to have!) is the wiring the same as on the house bank, or does the Echo or ACR have any weird effects?

Linkpro has an input to read the voltage on a second battery (start). I don't think you need to know amp-hrs on the start battery, just the voltage anyway.

[mitiempo]

I agree. A dedicated start battery doesn't have to be monitored, voltage is all that is needed. Victron's BMV-602 will tell you voltage on the start battery as well as full monitoring on the house bank.

The Echo Charge or ACR will have no effect on monitoring. Just remember that the shunt has to be the first connection after the negative post of the house bank.

Your schematic doesn't show fuses on each side of the Echo Charge near the positive posts. Also the switch in the connection to the house bank from the Echo isn't needed.

[mtompson]

Thanks guys, I'll have a go at wiring in a BMV-602 later on. There is a fuse for the Echo charge on the Start side, it uses one of the MRBF Terminals (might not be too clear in my diagram) I agree with adding one on the House side.

[mtompson]

I don't have time to wire the battery monitor to the Start bank at the moment, so for now...

[mitiempo]

Originally Posted by mtompson

There is a fuse for the Echo charge on the Start side, it uses one of the MRBF Terminals (might not be too clear in my diagram) I agree with adding one on the House side.

The Echo Charge cannot use one of the MRBF fuses. Every time the wire gauge gets smaller a new fuse for the smaller wire will be needed. The Echo Charge wire is sized for the 15 amp input/output it has. That wire will catch fire long before the MRBF fuse pops.

The only additional wire needed for the BMV-602 over the 600 is one to the start positive post, also fused near the terminal.

[mtompson]

Ok, is it not possible to get MRBF fuses down to 15amp? I had a very quick look at the blue sea site, they might just go down to 30?

[Maine Sail]

Originally Posted by mtompson

Ok, is it not possible to get MRBF fuses down to 15amp? I had a very quick look at the blue sea site, they might just go down to 30?

MRBF fuses go down to 30A and this is within the limits of the Echo's wire... We still don't know what size fuses you are using on house & start but you have 2/0 wire so 300A would be good if you are using 105C marine wire.....

[mtompson]

I can't really work out sizes for everything just yet, I'm still working out loads. The main reason I tagged a few lines with the 2/0 size was to show the run through without the need for new fuses, as you helped reduce my initial bunch of fuses earlier on.
Just to clarify, when you say that 30A is within the limits of the Echo wire, does that mean the fuse will go before the wire? Do you think it's best not to us an MRBF in this case?
Thanks

[Salty Skipper]

SIMPLE.... combine ALL batteries, one bank, one charging wire! keep one gp 24 aside for starting..(if your not lazy).if ever needed! Or, buy an expensive battery combiner, and endure the hook-up wiring involved! In my opinion, battery combiners were made for a market of insecure and paranoid boat owners! Overkill to say the least!