Battery Monitor

[dbsea]

I'm interested in a battery monitoring system. Seems like there are lots of options out there. How does one set this up for monitoring all 3 battery banks (House, Start, Thruster) independently, and ideally i'd want it to connect into my NEMA 2k and have bluetooth for my phone.

 

[Pilotnavigator]

Balmar sg200 will monitor the current in house bank and voltage of starter and thruster.

 

[Submariner]

I'm interested in a battery monitoring system. Seems like there are lots of options out there. How does one set this up for monitoring all 3 battery banks (House, Start, Thruster) independently, and ideally i'd want it to connect into my NEMA 2k and have bluetooth for my phone.

I use a battery monitor for the house bank. Something that tells me how many amp-hours remain. A fuel gauge for the house battery bank.

For the thruster and engine battery, they are usually at, or near, 100% state of charge, most of the time. They are only used for brief periods of time, starting the engine or using the thrusters when docking. For the thruster and engine battery, I installed a Victron Smart Battery Sense. They're like, $30/each. Connects via bluetooth to my phone. Tells me the voltage and the temperature. This lets me easily know that my engine and thruster batteries are healthy as I can monitor their voltage easily, at any time.

https://www.letsgochannelsurfing.com/smart-battery-sense

 

[SJI Sailor]

Martin, that looks good and very simple. One question: what does the Victron give you, besides Bluetooth, that just looking at the house voltage gauge doesn't give? Conversion to %, or history, or ... ?

 

[dbsea]

I'm interested in a battery monitoring system. Seems like there are lots of options out there. How does one set this up for monitoring all 3 battery banks (House, Start, Thruster) independently, and ideally i'd want it to connect into my NEMA 2k and have bluetooth for my phone.

I use a battery monitor for the house bank. Something that tells me how many amp-hours remain. A fuel gauge for the house battery bank.

For the thruster and engine battery, they are usually at, or near, 100% state of charge, most of the time. They are only used for brief periods of time, starting the engine or using the thrusters when docking. For the thruster and engine battery, I installed a Victron Smart Battery Sense. They're like, $30/each. Connects via bluetooth to my phone. Tells me the voltage and the temperature. This lets me easily know that my engine and thruster batteries are healthy as I can monitor their voltage easily, at any time.

https://www.letsgochannelsurfing.com/smart-battery-sense

Thanks Martin. I think i just want the smart shunt for my house bank, so i can measure the amp-hours from my phoen, but i have 4 batteries in my house bank and the wiring is confusing the heck out of me. :cry:

 

[Submariner]

Thanks Martin. I think i just want the smart shunt for my house bank, so i can measure the amp-hours from my phoen, but i have 4 batteries in my house bank and the wiring is confusing the heck out of me. :cry:

I can help with that. Let's get a date/time scheduled and I can meet with you on your boat.

 

[Submariner]

Martin, that looks good and very simple. One question: what does the Victron give you, besides Bluetooth, that just looking at the house voltage gauge doesn't give? Conversion to %, or history, or ... ?

Not every boat that RT makes comes with a voltage gauge.

My RT27-OB, NW edition came with no battery monitor or voltage meter. If I wanted to know the voltage of my house bank, I turned on the Garmin Chartplotter to see what it's "system voltage" was. If I wanted to know the voltage of my engine, I had to turn on the engine to accessory (not start the engine) and read the voltage on the Garmin chartplotter of the engine battery. The thruster battery, I would need to pull the battery out (very difficult to get at spot) and use a volt meter.

I think the LE's come with a voltage meter for all three banks, which would be nice.

The Battery Monitor keeps track of actual electrical consumption. Do I want to know my house bank is at 12.5volts before I go to bed, or do I want to know that I've consumed 40amp-hours out of a possible 99amp-hours, and my current electrical consumption is 6 amps. Which then tells me at this rate, I have 9.8 hours left, unless I turn off some stuff.

The Victron Smart Battery Sense's are an inexpensive way to get the voltage of the engine and thruster bank without having to install a volt meter in the boat and run wires between the battery and volt meter.

The Victron BMV712 battery monitor also keeps track of total number of discharges, deepest discharge, etc... So it provides some great stat's over time that let you know the overall health of your battery bank.

 

[Martin610]

I put in a shunt this winter. Very happy with the information I can get out of it. I went with Balmar SG205, which has the wireless option. I like the color display it has.

You do have to install a negative bus bar to ensure all he power goes through the shunt. I noticed that some of the cheap bus bars out there are brass, not copper. I would avoid those. Brass has much more resistance. You will probably have to make some additional cables or order some.

I don't think cables are all that hard to make and it gives you flexibility in the install. There are lots of YouTube videos on that subject.

When installing the gauge itself I drill the hole slightly undersize and then use a sanding drum until I get the fit I want.

-martin610

 

[dbsea]

Thanks all, great insights. Martin (Channel Surfer) has offered to come down and help me out. While I have two college degrees, power management still manages to make me feel somewhat dense. 🙂 With 4 house batteries and some connections that are different from the original wiring diagram, I just can't wrap my head around it. A negative bus bar sounds like a good idea... will plan out the best solution with Martin's assistance!

 

[Hamster]

I installed the Balmar SG200 with Bluetooth remote. Their website has good diagram of the architecture for putting the system together, plus a video. https://balmar.net/sg200-battery-monitor/

 

[Submariner]

You do have to install a negative bus bar to ensure all he power goes through the shunt. I noticed that some of the cheap bus bars out there are brass, not copper. I would avoid those. Brass has much more resistance.

Brass is an alloy of copper and zinc. As a bus bar, this would be a horrible choice on a boat surrounded by salt water. Also, don't use aluminum bus bars either. In addition, there are some steel bus bars plated in tin. Don't use those either on a boat.

Bus bars should be marine grade, which is tin plated copper. It's usually best to purchase components such as these from a marine store.