Chat with a Battle Born ProHere at Battle Born Batteries, our sales technicians have noticed an increase in calls specifically about the Victron Energy BMV battery monitors. This blog post will help with everything you need to know about wiring, programming, charging and installation for your battery monitor.
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
The BMV resets to “fully charged” when the voltage reading exceeds the charged voltage parameter. Simultaneously, the charge current is below the tail current parameter for a particular time known as the charged detection time. Charged voltage is defined as the voltage above which the BMV will calibrate itself above one hundred percent. You can use Bluetooth to configure the BMV opening the Victron Connect app and selecting the BMV.
Troubleshooting
Sometimes after the initial setup, the BMV won’t display the correct readings. Make sure that you bring your battery bank to full a charge (14.2v-14.6v) after setting up the BMV. The component will not show the correct information until you charge them completely!
Also, it’s important to confirm that the shunt readouts make sense. If you are seeing inaccurate numbers, your shunt may not match the settings or wiring and will need to be adjusted.
For more information, check out our newest FAQ video featuring our CEO Denis onsite in a van to demonstrate the BMV-700’s capabilities.
If you have any questions when it comes to programming your battery monitor, please give us a call at (855) 292-2831 or email us at [email protected].
All great information!
It’s important to note however that battery starts synchronized should be turned off.
This will prevent the issue of automatically resetting the state of charge to 100% when in fact the batteries are not. For instance if the batteries were depleted completely and the BMS in the batteries shut down then as soon as the BMS was restarted it would display 100% state of charge which would not be correct.
Hi Jordan. I just had this problem. My batteries shut down because they were trying to be charged when they were under 32 deg. My BMV immediately reset to 100%. I turned off the batter start synchronize and hope it fixes the issue! Thank you for you comment.
If the ‘Battery Starts Synchronized’ is left in the ‘On’ position then the BMV712 will show 100% after starting up from a no voltage situation such as disconnecting batteries completely or a BMS disconnect scenario…this is all normal and your statement is correct. However, the SOC will correct itself as soon as the BMV-712 sees charge and discharge cycle and the calibration will be correct. So my advice is to leave the BMV-712 software switch in the ‘On’ position for ‘Battery Starts Synchronized’ and let it sort itself out rather than see an ‘unknown’ SOC until it does.
I am trying to set my Victron BMV-712 to Bluetooth. The function numbers only go to 69. I cant go to 70, Start Synchronized, or 71, Bluetooth mode. ant ideas?
Hi there! Thanks for reaching out. Our team can help you troubleshoot the BMV if you give them a call at 855-292-2831.