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Power to 24v panel - easy to isolate?

Scott SV Tengah
 

All,

As mentioned in my long post about my lithium installation, I'm still trying to figure out a way to install a load disconnect solenoid that will be controlled by the Battery Management System (BMS). This would disconnect loads in the event of low voltage in one of the lifepo4 cells.

https://amelyachtowners.groups.io/g/main/message/47785

When I tried to install the Victron BP-220 battery protect, Victron's load disconnect solenoid, the 220 amp capacity was not nearly enough given that all of the loads ran through it. It melted pretty quickly. One solution suggested to me was only to have the 24v panel running through the BP-220. That makes sense because if we disconnect all power to the 24v panel, I believe all electrical devices are disabled. 

Have any of you tried to trace from the battery switch to the 24v panel? I have an A54, but I presume the SM and earlier are similar in this regard.


--
Scott 
2007 A54 #69
SV Tengah
http://www.svtengah.com

Arno Luijten
 

Hi Scott,

The main feeder cable to the 24 volt panel is coming from the busbar-stud that sits on the wall that separates the battery compartment from the compartment that contains the main power switches. There are several cables stacked together there, one of those goes to the 24V panel. But be aware the 24 volt panel does not switch all consumers. The nav-area has a separate line. This also feeds the 24V-12V converters in the cabinet under the nav table. So disabling the  24V panel does not eliminate all power draw.

You may want to have a look at this product. It can handle 500A: https://tbs-electronics.com/product-category/dc-modular-fuseholders-busbars/
This means you can use it in your primary battery cable. Do think about how to connect this as you will need to be able to charge the battery even if the switch has disconnected the battery. So the charger should be connected directly to the battery. If I remember correctly Amel  connected the chargers on the battery side of the main power switches as well. So even if you disconnect all power the batteries can still be charged.

Regards,

Arno Luijten
SV Luna,
A54-121