The Setup
This post will focus on the Victron BMV-712 Smart Battery Monitor setup. If you are interested in the Victron BMV-700 or BMV-702 with a Bluetooth dongle, check out our other blog post. First, make sure you have all of the parts you ordered before installing. Some of the necessary components include wires, like the RJ12 type cable, which connects to the display, or positive sensor wires. Let’s take inventory of the included parts: Shunt, Display, RJ12 cable to connect the shunt to the display, and two positive power supply cables. To monitor a single battery bank, we will only use one of the positive supply cables.
For the 700, 702 and 712 models, two cables are required to monitor your battery bank. One cable (red wire) connects to a positive terminal of your LiFePO4 battery bank. The other cable (RJ12) is for connecting to the display. There is a second red wire included in the 702 and 712 models and is used for monitoring a second battery bank and/or a starter battery voltage. Also, Victron has an optional dual wired temp sensor available (sold separately).
Reference Victron Energy’s BMV-712 quick installation guide for more information.
How to Wire
When it comes to wiring the display and shunt, the shunt creates a low-resistance path for electric current to pass through and obtain accurate readings that will be sent to the LED display. The LED display is circular and used for mounting somewhere in your vehicle with Bluetooth access via smartphone or tablet. Make sure to read the labeling on the shunt for proper wiring. You will notice “BATT” and “LOAD” clearly labeled on the shunt. It is recommended to install the last negative cable coming off the batteries on the “BATT” side of the shunt. The other side of the shunt is labeled “LOAD” which will go to a negative busbar or distribution panel to properly obtain readings. Cables needed to properly wire the shunt should be congruent with the jumper cables interconnecting batteries in a system. This will ensure proper current flow through the shunt. Here’s one example of a wiring diagram:
How to Program
You can use Bluetooth to configure the BMV by opening the Victron Connect app and selecting the device. For our batteries, use the following settings to program the BMV-712 Smart Battery Monitor:- Battery Capacity: Total Ah of your bank of batteries
- Charged voltage: 14.4V but note that this number should be about .1 or .2 volts below the charging voltage set in your charging device
- Discharge Floor: 0%
- Tail Current: 2-4% is good
- Charged Detection Time: 3m
- Peukert Exponent: 1.05
- Charge Efficiency Factor: 99%
- Current threshold: 0.10A
- Time to go averaging period 3m
- Battery Starts Synchronized: blue button should be to the right
- State of Charge: leave alone
- Synchronize SOC to 100%: Leave alone, this device will sync itself at the top of the charge
- Zero Current Calibration: Leave alone