I just finished installing the Victron BMV712 ‘Smart’ (with Bluetooth) battery monitor to measure current flow and battery capacity for the 4 battery house bank. In principle it’s an easy install, but limited access to the 4 house batteries through the port side cockpit locker makes the project a bit more complex on the R29.
The problem is identifying all the negative power (solar, charger and alternator) and load (negative buss bar for the 12 volt system) leads and then connecting them to one side of the shunt used to measure current flow. Because the head room in the battery compartment is so limited, I removed and temporarily unplugged the cockpit refrigerator and cut two 6” diameter holes in the floor of frig compartment giving me direct access to the posts on the batteries I could not reach via the cockpit locker. The biggest challenge in this respect is the negative lead from the house battery bank to the engine ground that connects to the engine via the negative post on the engine battery that is furthest forward in the battery locker. I established exactly where to cut by drilling exploratory holes and observing the position of the drill bit relative to the posts I needed to access. In this case I needed to reroute the cable between the negative post on the engine battery and the house bank to the shunt. It worked out well but remember to wrap the lugs on cable leads you are moving with tape to ensure they don’t touch a positive battery lug while you are relocating them. Be careful with the swing of your wrenches as well!
Once I had screwed the monitor shunt to the wall of the battery locker close by the negative house battery post to which most of the negative power and load leads had been fastened, I attached those leads to the shunt and used a short length of new battery cable to make the new connection between the shunt and the and the house bank. I then plugged in the phone cable carrying the data to the monitor display and the red wire providing power to the monitor and checked that the system worked by turning on the three power sources (solar, charger and engine) in turn. I then checked the draw from the various appliances and devices by turning on one after another on their own. Preliminary observations: the Garmin display is a real hog but the Nova Kool frig, the Webasto heater and the propane solenoid are surprisingly good. I haven’t tried the TVs or radio yet.
I haven’t installed the battery monitor display just below the propane controller in the salon. And I may never permanently install it since using the Victron Connect app I can check what’s going on with the batteries on my iPhone. At the moment the display is in a small plastic box sitting close by the house battery bank.
I also plan to fill the two 6” holes in the frig compartment floor with deck hatches with screw on covers. There is room under the frig for the one hatch beneath it.
Let me know if you have any questions.
NOTE: remember to turn off all significant draws (frig, instruments, etc.) on the house bank, switch off the batteries and the charger/inverter switch, and disconnect the solar panel at the controller while working on the project. I put a switch and breaker on the positive wire to the controller.
The problem is identifying all the negative power (solar, charger and alternator) and load (negative buss bar for the 12 volt system) leads and then connecting them to one side of the shunt used to measure current flow. Because the head room in the battery compartment is so limited, I removed and temporarily unplugged the cockpit refrigerator and cut two 6” diameter holes in the floor of frig compartment giving me direct access to the posts on the batteries I could not reach via the cockpit locker. The biggest challenge in this respect is the negative lead from the house battery bank to the engine ground that connects to the engine via the negative post on the engine battery that is furthest forward in the battery locker. I established exactly where to cut by drilling exploratory holes and observing the position of the drill bit relative to the posts I needed to access. In this case I needed to reroute the cable between the negative post on the engine battery and the house bank to the shunt. It worked out well but remember to wrap the lugs on cable leads you are moving with tape to ensure they don’t touch a positive battery lug while you are relocating them. Be careful with the swing of your wrenches as well!
Once I had screwed the monitor shunt to the wall of the battery locker close by the negative house battery post to which most of the negative power and load leads had been fastened, I attached those leads to the shunt and used a short length of new battery cable to make the new connection between the shunt and the and the house bank. I then plugged in the phone cable carrying the data to the monitor display and the red wire providing power to the monitor and checked that the system worked by turning on the three power sources (solar, charger and engine) in turn. I then checked the draw from the various appliances and devices by turning on one after another on their own. Preliminary observations: the Garmin display is a real hog but the Nova Kool frig, the Webasto heater and the propane solenoid are surprisingly good. I haven’t tried the TVs or radio yet.
I haven’t installed the battery monitor display just below the propane controller in the salon. And I may never permanently install it since using the Victron Connect app I can check what’s going on with the batteries on my iPhone. At the moment the display is in a small plastic box sitting close by the house battery bank.
I also plan to fill the two 6” holes in the frig compartment floor with deck hatches with screw on covers. There is room under the frig for the one hatch beneath it.
Let me know if you have any questions.
NOTE: remember to turn off all significant draws (frig, instruments, etc.) on the house bank, switch off the batteries and the charger/inverter switch, and disconnect the solar panel at the controller while working on the project. I put a switch and breaker on the positive wire to the controller.