Battery Management

[Scott T-Bird]

I could "close the loop" on this by adding a 1-2-OFF switch to select which bank is involved in the 1-2-BOTH-OFF existing scheme.

Rather than let a sleeping dog lie I'm left wondering why you haven't considered using a DCP switch in your transformations. You stated that you want to separate sailing loads from house loads. Obviously, that would suggest that you want both banks on and isolated, which you can do with DCP but you can't with 1+2+B+Off. You would need to add 2 on-off switches so that you can combine and isolate a bad bank (when necessary), but it seems like something you might consider.

 

[jviss]

You mean the BSS DCP switch? First, I never want to manually combine the banks, and second, it doesn't afford the flexibility of selecting which bank for which set of loads.

 

[Scott T-Bird]

It sounded like you want to separate the sailing loads and the house loads. If you want both on at the same time, DCP does that and 1+2+B does not give you that option. You don't have to ever combine the banks when you add the 2 on-off switches. You simply use the Combine position to select either one bank or the other by turning off the bank that you don't want by selecting which on-off switch to switch off. Yes, it means 3 switches, but on a regular basis you are only turning DCP "ON" to provide what you want and you normally just leave the other 2 switches on all the time (and usually out of sight, too). You also want to install ACR for charging both banks.

By installing ACR with 2 on-off switches, it provides the ultimate flexibility. You can run both banks separately at the same time, or you can select any bank you want for any purpose and turn off any bank you want without affecting the other. I can't think of any function that you can't do, and you never have to combine 2 banks for any reason except when you want to (if there ever were a reason).

 

[jviss]

I don't think so, Scott. Maybe I wasn't clear above. I'll have two 1-2-OFF switches, one feeding each load zone. The legacy 1-2-BOTH-OFF will be to maintain my selection of bank 1 or the engine batt for starting, etc. Ot something like that. : ) I'll have to draw the schematic.

 

[Scott T-Bird]

I guess that begs the question ... how do you want to feed the load zones? Do you have one panel for house loads and another panel for sailing loads? I'm not sure I understand how you would use the 2 switches for flexibility. It seems like you are still locking out one bank when you use the other.

If you had DCP, you can feed 2 panels simultaneously and independently. I guess you would put the starter on one pole or the other. You would have 2 on-off switches to route the individual battery banks to the DCP switch. With the 3 switches in place, you can put all loads on one battery bank or the other if a bank goes bad. You simply switch off the bad bank and set DCP to combine. Or you can continue to use only the good bank without combining the panels with the normal "ON" setting. You would need to have power to the starter, though, either way, which you can do with "Combine" as necessary.

 

[jviss]

Scott, I confess I don't understand your advocacy for the DCP switch. It does nothing for the design I articulated, except perhaps add a switch, and introduce a mode that is not in the design.

As I stated earlier, the design of my panel, and many others, is such that I can easily break off one column or two by removing the horizontal positive jumpers between vertical bus bars. Once that is done I can feed those bus bars with a 1-2-OFF switch, common to the bus and 1 and 2 to banks 1 and 2. Simple.

The switch is the BSS #6008

 

[Scott T-Bird]

I'm sure I'm missing something but I thought one of your intentions is to separate the loads. Those switches are only 3 poles, so neither switch separates the loads. They only isolate the sources. It seems to me that if you want to separate the loads, you can do that with a 4-pole switch. But I do see how you can do that with 2 (3-pole) switches.

 

[Davidasailor26]

I'm sure I'm missing something but I thought one of your intentions is to separate the loads. Those switches are only 3 poles, so neither switch separates the loads. They only isolate the sources. It seems to me that if you want to separate the loads, you can do that with a 4-pole switch. But I do see how you can do that with 2 switches.

I think he’s saying that he can split his supply panel into 2 busses, and feed each bus with a 1-2-B switch. That way he can select which bank feeds each half of the loads, or he can put either switch on B to tie both banks together.

 

[jviss]

I think he’s saying that he can split his supply panel into 2 busses, and feed each bus with a 1-2-B switch. That way he can select which bank feeds each half of the loads, or he can put either switch on B to tie both banks together.

Bingo.

 

[Scott T-Bird]

Yes, I see it and it is simple and efficient.