Looking for additional Information on my battery health

[profcbutler]

This past month I took possession of my new 2025 Ranger Tug R25. This has been one of the best customer experience I have ever had with a major purchase. I can't say enough about the entire support team at Pocket Yachts in Grasonville!
I am posting this question on Tugnuts to see if anyone has gone down the road I am looking to take.
I am lucky enough to have purchased the R25 at a time when they were offering a powerful lithium configuration. I have the luxury edition with 600 amp hours on the house battery bank. I have already seen the value of this when I take the boat out for hours and run the AC. It seems I could be out for days without having to hook back up to shore power. Although, I am incredibly happy everything seems to be working properly, I am limited to what I can see as it relates to the individual components of the electrical charging system.
I have the BMV-712 Smart Battery Monitor to provide me very basic information. However, it is very limited (see attached Pic)
Has anyone updated a 2025 Ranger tug with a more detailed charge monitor? What i would love to see is the health of the Engine, thruster, and house battery with how effective each piece of the charging system actual is (Engine, Shore, and Solar). I have seen this type of monitor on larger boats and RV's (i.e. Victron Energy GX touch). It clearly shows all parts of the system and how the pieces are performing with the ultimate goal of charging the battery(s). I know Ranger did not install all Victron pieces when building the system. I am sure they all integrate well but not so sure it can be upgraded to support a better monitor. Looking at simple functions like... how well the solar panel is charging. I know the Victron GX display does this but not sure it would work in the current factory configuration without a major overhaul.
Does anyone have any experience with this? I do not want to build a whole new system... Just looking for a simple solution to tap into the existing structure to get a better view of all the pieces. Hope this all makes sense.

 

[freedomvango]

You can easily add two more shunts to those batteries and do the same thing.
You cannot do that without adding a shunt for each battery bank

If you go into the other tabs, there are more data points to check out.

If you want all that data, you must change everything to victron like I have on my r23.

If you just want to know what each battery bank is doing, like what you already have, you can add two smart shunts - https://vanpartswarehouse.com/produ...rtshunt-500a-50mv?_pos=2&_sid=53cecddb5&_ss=r
There is no easy way to get a Cerbo GX-type display without an overhaul. But this will at least give you application access like you currently have, without having to run cable for more displays.

If you simply want to know the voltage history, you can use a smart battery sense - https://vanpartswarehouse.com/products/smart-battery-sense?_pos=1&_sid=47cc945f3&_ss=r
This will give you a voltage over time, at least in the historical data on it, which is better than nothing.

 

[Submariner]

Battery Monitor (BMV-712) is on the house bank. That's how you know where you are at with your house battery bank. Being a 2025 model, you have LiFePo4 for the house battery bank. With 600 amp hours, you should be able to draw down to 20% SOC and still maintain voltage above 12.0 volts.

For the engine and thruster battery... the engine battery is a starting battery, the thruster battery is most likely a deep cycle AGM battery (110ah). Being that both are used for short term, and not deep cycle loads, a simple Victron Battery Sense ($40/each) would provide battery voltage readings. These batteries should be 12.8 volts or greater, most of the time. Because they are discharged and charged right away, I personally don't see the value in adding a battery monitor (like the BMV-712) to the engine or thruster banks. The Victron Battery Sense added, gives me voltage readings on my phone, and that alone is enough for me to know the health of my thruster and engine battery.

With you having LFP batteries for your house bank, it's unlikely you'll have any battery problems for years to come. Channel Surfing is turning 5 years old next month, the thruster and engine battery are still doing great. I'll probably change them at the end of this season just because they'll be over 5 years old. My house bank is LFP, and is 3 years old, and has no issues at all.

Battery Sense

Victron: Battery Sense | LetsGoChannelSurfing

www.letsgochannelsurfing.com

Battery Monitor

House Battery-Monitor | LetsGoChannelSurfing

www.letsgochannelsurfing.com

I also have a CerboGX installed, but this is definitely optional. I primarily use my CerboGX so I get battery stat's on my phone, when I'm away from the boat (remote monitoring).

Boat Remote Monitoring

Boat Monitoring | LetsGoChannelSurfing

www.letsgochannelsurfing.com

Here's a visual on how I keep track of the health of all my batteries on Channel Surfing. This is on my phone.
BMV-712 on my house bank.
Battery Sense on the thruster and engine bank.
Victron solar charger, so I can easily keep track of solar from day to day. (to quantify how beneficial it is to have 420 watts of Solar).
CerboGX I have, for remote monitoring as I have Internet on the boat 24x7, that allows the CerboGX to upload its data.

 

[freedomvango]

Battery Monitor (BMV-712) is on the house bank. That's how you know where you are at with your house battery bank. Being a 2025 model, you have LiFePo4 for the house battery bank. With 600 amp hours, you should be able to draw down to 20% SOC and still maintain voltage above 12.0 volts.

For the engine and thruster battery... the engine battery is a starting battery, the thruster battery is most likely a deep cycle AGM battery (110ah). Being that both are used for short term, and not deep cycle loads, a simple Victron Battery Sense ($40/each) would provide battery voltage readings. These batteries should be 12.8 volts or greater, most of the time. Because they are discharged and charged right away, I personally don't see the value in adding a battery monitor (like the BMV-712) to the engine or thruster banks. The Victron Battery Sense added, gives me voltage readings on my phone, and that alone is enough for me to know the health of my thruster and engine battery.

With you having LFP batteries for your house bank, it's unlikely you'll have any battery problems for years to come. Channel Surfing is turning 5 years old next month, the thruster and engine battery are still doing great. I'll probably change them at the end of this season just because they'll be over 5 years old. My house bank is LFP, and is 3 years old, and has no issues at all.

Battery Sense

Victron: Battery Sense | LetsGoChannelSurfing

www.letsgochannelsurfing.com

Battery Monitor

House Battery-Monitor | LetsGoChannelSurfing

www.letsgochannelsurfing.com

I also have a CerboGX installed, but this is definitely optional. I primarily use my CerboGX so I get battery stat's on my phone, when I'm away from the boat (remote monitoring).

Boat Remote Monitoring

Boat Monitoring | LetsGoChannelSurfing

www.letsgochannelsurfing.com

Here's a visual on how I keep track of the health of all my batteries on Channel Surfing. This is on my phone.
BMV-712 on my house bank.
Battery Sense on the thruster and engine bank.
Victron solar charger, so I can easily keep track of solar from day to day. (to quantify how beneficial it is to have 420 watts of Solar).
CerboGX I have, for remote monitoring as I have Internet on the boat 24x7, that allows the CerboGX to upload its data.

Glad to know we are on the same page!

 

[Jcat2010]

as noted above, there's limited information needed for the start and thruster batteries. There are many Bluetooth monitors that will provide voltage info. What's important for starter and thruster is terminal voltage, and the ability to monitor drawdown voltage under use. For instance, my starter currently charges fully and pulls down to just under 12v during a start. Same for thruster. Once a year I have them checked at local napa. With solar charger there's not a lot to worry about unless the profile starts to degrade. As to the lithium there's plenty of good info in this thread and others

 

[profcbutler]

You can easily add two more shunts to those batteries and do the same thing.
You cannot do that without adding a shunt for each battery bank

If you go into the other tabs, there are more data points to check out.

If you want all that data, you must change everything to victron like I have on my r23.

If you just want to know what each battery bank is doing, like what you already have, you can add two smart shunts - https://vanpartswarehouse.com/produ...rtshunt-500a-50mv?_pos=2&_sid=53cecddb5&_ss=r
There is no easy way to get a Cerbo GX-type display without an overhaul. But this will at least give you application access like you currently have, without having to run cable for more displays.

If you simply want to know the voltage history, you can use a smart battery sense - https://vanpartswarehouse.com/products/smart-battery-sense?_pos=1&_sid=47cc945f3&_ss=r
This will give you a voltage over time, at least in the historical data on it, which is better than nothing.

Thank you! that really helps me understand the power of those shunts! I will also pick up those Battery sensors I did nor realize there was a lower cost solution to the shunts when it comes to monitoring lead acids.

 

[profcbutler]

Battery Monitor (BMV-712) is on the house bank. That's how you know where you are at with your house battery bank. Being a 2025 model, you have LiFePo4 for the house battery bank. With 600 amp hours, you should be able to draw down to 20% SOC and still maintain voltage above 12.0 volts.

For the engine and thruster battery... the engine battery is a starting battery, the thruster battery is most likely a deep cycle AGM battery (110ah). Being that both are used for short term, and not deep cycle loads, a simple Victron Battery Sense ($40/each) would provide battery voltage readings. These batteries should be 12.8 volts or greater, most of the time. Because they are discharged and charged right away, I personally don't see the value in adding a battery monitor (like the BMV-712) to the engine or thruster banks. The Victron Battery Sense added, gives me voltage readings on my phone, and that alone is enough for me to know the health of my thruster and engine battery.

With you having LFP batteries for your house bank, it's unlikely you'll have any battery problems for years to come. Channel Surfing is turning 5 years old next month, the thruster and engine battery are still doing great. I'll probably change them at the end of this season just because they'll be over 5 years old. My house bank is LFP, and is 3 years old, and has no issues at all.

Battery Sense

Victron: Battery Sense | LetsGoChannelSurfing

www.letsgochannelsurfing.com

Battery Monitor

House Battery-Monitor | LetsGoChannelSurfing

www.letsgochannelsurfing.com

I also have a CerboGX installed, but this is definitely optional. I primarily use my CerboGX so I get battery stat's on my phone, when I'm away from the boat (remote monitoring).

Boat Remote Monitoring

Boat Monitoring | LetsGoChannelSurfing

www.letsgochannelsurfing.com

Here's a visual on how I keep track of the health of all my batteries on Channel Surfing. This is on my phone.
BMV-712 on my house bank.
Battery Sense on the thruster and engine bank.
Victron solar charger, so I can easily keep track of solar from day to day. (to quantify how beneficial it is to have 420 watts of Solar).
CerboGX I have, for remote monitoring as I have Internet on the boat 24x7, that allows the CerboGX to upload its data.

View attachment 25396

Martin, I very much appreciate your detailed response. The content you post on YouTube is incredible. I have been a fan for years. Your thoughtful discussions on many topics helped me to decide on buying my Ranger Tug.
I did not realize there was a low cost solution to monitoring voltage and temp on the starter and thruster battery (through the Victron app) until seeing some of these replies. I know you covered some of this in your videos but until I took possession of the boat a couple weeks ago it did not make sense (until now!) This is exactly what I am looking for (i will link to it from your amazon site). It is also good to hear that the base configuration is pretty solid from Ranger Tug as well.

The only thing I need to figure out at this point is if there is any way to monitor the output of the Solar panel. I know I will get 60 amps from the Motor (at specific rpm). I know I will get 60 amps for shore power when connected...You are showing the Victron Sun monitor on your app. With what I currently have installed I am not sure if that device would plug and play for me. Again, I know Ranger mixed a few products with this configuration. Could I install the MPPT150/35 on top of what is already there to get the data you are seeing?

 

[Submariner]

The only thing I need to figure out at this point is if there is any way to monitor the output of the Solar panel. I know I will get 60 amps from the Motor (at specific rpm). I know I will get 60 amps for shore power when connected...You are showing the Victron Sun monitor on your app. With what I currently have installed I am not sure if that device would plug and play for me. Again, I know Ranger mixed a few products with this configuration. Could I install the MPPT150/35 on top of what is already there to get the data you are seeing?

The Yamaha F250/300 has a 70 amp alternator. At best, it'll output 50 amps (I've measured it, using the BMV-712). However, with LFP, this must be rate-limited to prevent the alternator from overheating. LFP is a very large battery bank, and it's just not a large alternator on the Yamaha. The alternator isn't designed to run at 100% load for many hours, non-stop. The most you should expect from the engine to house is 40amps. (It's rate limited via configuration in the DMT1250). The boat needs to be up on plane to get this much, which also means you're underway with the chartplotter running, RADAR, etc... Generally speaking, the boat will consume about 15 amps underway leaving another 15-25 amps available for charging the house bank while under way.

On shorepower, you will get 60 amps of charging from the battery charger, and most things on the boat are powered off which helps speed things up at the dock. When we're down around 20-50% SOC on a trip, and then spend a few hours driving back to our home port, rarely does the battery get back to fully charged, underway.

Solar is key. The ePever solar controller is MPPT which is great. For fantastic instrumentation, a Victron Smart Solar controller, MPPT, will give you real stats on how much solar you saw today, yesterday, last week, last month. It's fairly straightforward to add a Victron 100/30 or 150/35 to an LE. It's a fairly common upgrade on the LE for a specific reason. The factory installation, the DMT1250 is the engine to house charger and it's also the solar to house charger. It takes an input from the engine or solar, and whichever is stronger, wins. For example, if the engine is running, most likely solar is less amps (on the factory panel), so the engine is charging the house and the power from solar is discarded. Solar could work with engine charging to help keep that large house bank charged, but would require a dedicated solar controller be installed. Once you upgrade the solar controller, that puts you in a position to consider upgrading your solar. Depending on when you bought your 2025 LE, you either have a 175watt panel, or a 220 watt solar panel. With a 150/35 VIctron controller, you could double up your solar and get to 350-400 watts. At that point, shorepower becomes optional during boating season.

In this video, I walk-through adding a solar controller to an LE. Start at timestamp 13:00.

Solar Upgrades Playlist

Solar Power on a Boat

Share your videos with friends, family, and the world

youtube.com

 

[Submariner]

Martin, I very much appreciate your detailed response. The content you post on YouTube is incredible. I have been a fan for years. Your thoughtful discussions on many topics helped me to decide on buying my Ranger Tug.

Thank you!! I'm glad you found our content helpful.

 

[profcbutler]

The Yamaha F250/300 has a 70 amp alternator. At best, it'll output 50 amps (I've measured it, using the BMV-712). However, with LFP, this must be rate-limited to prevent the alternator from overheating. LFP is a very large battery bank, and it's just not a large alternator on the Yamaha. The alternator isn't designed to run at 100% load for many hours, non-stop. The most you should expect from the engine to house is 40amps. (It's rate limited via configuration in the DMT1250). The boat needs to be up on plane to get this much, which also means you're underway with the chartplotter running, RADAR, etc... Generally speaking, the boat will consume about 15 amps underway leaving another 15-25 amps available for charging the house bank while under way.

On shorepower, you will get 60 amps of charging from the battery charger, and most things on the boat are powered off which helps speed things up at the dock. When we're down around 20-50% SOC on a trip, and then spend a few hours driving back to our home port, rarely does the battery get back to fully charged, underway.

Solar is key. The ePever solar controller is MPPT which is great. For fantastic instrumentation, a Victron Smart Solar controller, MPPT, will give you real stats on how much solar you saw today, yesterday, last week, last month. It's fairly straightforward to add a Victron 100/30 or 150/35 to an LE. It's a fairly common upgrade on the LE for a specific reason. The factory installation, the DMT1250 is the engine to house charger and it's also the solar to house charger. It takes an input from the engine or solar, and whichever is stronger, wins. For example, if the engine is running, most likely solar is less amps (on the factory panel), so the engine is charging the house and the power from solar is discarded. Solar could work with engine charging to help keep that large house bank charged, but would require a dedicated solar controller be installed. Once you upgrade the solar controller, that puts you in a position to consider upgrading your solar. Depending on when you bought your 2025 LE, you either have a 175watt panel, or a 220 watt solar panel. With a 150/35 VIctron controller, you could double up your solar and get to 350-400 watts. At that point, shorepower becomes optional during boating season.

In this video, I walk-through adding a solar controller to an LE. Start at timestamp 13:00.

Solar Upgrades Playlist

Solar Power on a Boat

Share your videos with friends, family, and the world

youtube.com

Martin, thanks again. This will be a project I will tackle in the fall. Your point about being able to take advantage of charging from both the engine and solar panel at the same time is a huge advantage and the fact that it opens up additional monitoring is the icing on the cake! Very much appreciated!

I will be reviewing again all your videos about the electrical system upgrades....especially now, that I understand a little bit more about how all this works.

 

[JunieBird]

Martin, thanks again. This will be a project I will tackle in the fall. Your point about being able to take advantage of charging from both the engine and solar panel at the same time is a huge advantage and the fact that it opens up additional monitoring is the icing on the cake! Very much appreciated!

I will be reviewing again all your videos about the electrical system upgrades....especially now, that I understand a little bit more about how all this works.

Martin, along the house battery charging theme.. our C-288 has the LIPO 600A house set up- recently, the KISEA charger stopped charging the house bank if the 'inverter switch' was on while on shore power (charger states batteries are full/float). The solar panels will charge the house batteries while on shore power. The charger will only charge the house batteries, pushing 60A, when the main house battery switch is in 'off' position. The bank drained as we were on shore power and the fridge was keeping the beer cold. ..yet the charger stated all was good. When on shore power, the KISEA states that all batteries are full while the Balmar shows 0 minutes left and the inverter monitor gives the low voltage code. This is a new issue... Thank you

 

[Submariner]

Martin, along the house battery charging theme.. our C-288 has the LIPO 600A house set up- recently, the KISEA charger stopped charging the house bank if the 'inverter switch' was on while on shore power (charger states batteries are full/float). The solar panels will charge the house batteries while on shore power. The charger will only charge the house batteries, pushing 60A, when the main house battery switch is in 'off' position. The bank drained as we were on shore power and the fridge was keeping the beer cold. ..yet the charger stated all was good. When on shore power, the KISEA states that all batteries are full while the Balmar shows 0 minutes left and the inverter monitor gives the low voltage code. This is a new issue... Thank you

When you turn on the inverter, it makes 120volt AC from your house bank which is at 12 volt DC.

The AC panel can't be energized by both the inverter and shorepower at the same time, else bad things happen. This is why the AC panel has a mechanical interlock preventing that. However.. you could turn on the inverter, and then energize the 120volt AC panel from shorepower. The inverter consumes power just being on even when it's not powering anything. It makes no sense to have the inverter on while connected to shorepower. If you were to ever work on the 120volt AC power on the boat, you'd want to disconnect shorepower and also turn off the inverter via the 12volt disconnect switch (isolate it) to be safe while you work.

You can turn on the inverter and power the 120volt AC panel off the inverter and then turn on the battery charger. This drains the battery as the battery charger is powered via the inverter which is powered via the battery. Left like this long enough, the inverter will report a low voltage alarm as it drains the battery.

It's best to only use the inverter away from the dock, when not connected to shorepower.

I understand it can be somewhat confusing. The boat is primarily powered by 12 volts DC power, via the batteries. When we're on shorepower with the battery charger turned on, the refrigerator will consume from the battery, which is replenished by the battery charger that is powered via shorepower.

All the 120volt AC loads are labeled on the AC panel with their breakers to turn on/off. If you don't see a device listed there, then assume it runs off 12 volts DC.

 

[JunieBird]

The inverter has an integrated load transfer switch to transfer 120V shore power to the breaker panel when on shore power. The 'house/inverter' switch is either on or off. When off, no house power. The battery charger charges. When on, and on shore power, the battery charger does not charge, but solar panels do.. The charger is powered and (power confirmed to breaker as the hot water heater will come on). So gremlin some where. The batteries should maintain a charge while on shore power and the house switch is 'on'.

 

[profcbutler]

Martin, thanks again. This will be a project I will tackle in the fall. Your point about being able to take advantage of charging from both the engine and solar panel at the same time is a huge advantage and the fact that it opens up additional monitoring is the icing on the cake! Very much appreciated!

I will be reviewing again all your videos about the electrical system upgrades....especially now, that I understand a little bit more about how all this works.

If you dont mind....One last question about the victron Battery Sensors I can use for the start and Thruster Batteries. Once added these additional circuits will add a parasitic drain to each respective Battery. Is this drain a concern when leaving the boat off shore power and not charging? I know it's probably not a lot (i hate parasitic drains 🙂)

 

[Submariner]

If you dont mind....One last question about the victron Battery Sensors I can use for the start and Thruster Batteries. Once added these additional circuits will add a parasitic drain to each respective Battery. Is this drain a concern when leaving the boat off shore power and not charging? I know it's probably not a lot (i hate parasitic drains 🙂)

The drain is miniscule. Nothing to worry about.

 

[Submariner]

The inverter has an integrated load transfer switch to transfer 120V shore power to the breaker panel when on shore power. The 'house/inverter' switch is either on or off. When off, no house power. The battery charger charges. When on, and on shore power, the battery charger does not charge, but solar panels do.. The charger is powered and (power confirmed to breaker as the hot water heater will come on). So gremlin some where. The batteries should maintain a charge while on shore power and the house switch is 'on'.

The outboard versions don't have inverter/chargers. They have an inverter, and a battery charger. Since they are separate devices, there is no automatic load transfer. The inboards generally do have inverter/chargers, but not all. A friend of mine has a C28, with an inboard engine and has a dedicated inverter and charger, exactly as my R27-OB has.

 

[profcbutler]

The drain is miniscule. Nothing to worry about.

I feel better, Thanks a bunch! I just watched your lower unit impeller change that you posted yesterday! As always you explained and demonstrated in a clear and easy to understand format. I now feel much more comfortable attempting that job!

 

[JunieBird]

The outboard versions don't have inverter/chargers. They have an inverter, and a battery charger. Since they are separate devices, there is no automatic load transfer. The inboards generally do have inverter/chargers, but not all. A friend of mine has a C28, with an inboard engine and has a dedicated inverter and charger, exactly as my R27-OB has.

yes, the c-288 has and inverter with an integrated load transfer switch, and a separate battery charger. The house bank should remain fully charged, when on shore power, regardless of reasonable 12V and/or 120V load. That is the new issue. The charger does not keep up 'refreshing' the 12V load while on shore power.

 

[QueenBeeII]

Regarding alternator charge while underway, I’m seeing a negative current draw via the smart shunt, shouldn’t that be a positive number? When accounting for the basic electronics ie Garmin 7612 chartplotter, VHF, Volvo engine display, Fusion radio and primary refrigerator, rear fridge set to off. I had this looked at my a marine electrician who is upgrading our solar. We determined that the eng/ house ACR was not functioning properly so I replaced that and had the alternator tested by a highly recommended local shop, it was within factory specs. My battery voltage will drop some underway but seems to come back up to a degree.
At the end of the day I’m concerned about the negative current number while running.
Here is a screenshot of the app
Should I continue to be concerned or is this expected. If not any ideas on what to check next? Thanks for any feedback.

 

[Submariner]

Regarding alternator charge while underway, I’m seeing a negative current draw via the smart shunt, shouldn’t that be a positive number? When accounting for the basic electronics ie Garmin 7612 chartplotter, VHF, Volvo engine display, Fusion radio and primary refrigerator, rear fridge set to off. I had this looked at my a marine electrician who is upgrading our solar. We determined that the eng/ house ACR was not functioning properly so I replaced that and had the alternator tested by a highly recommended local shop, it was within factory specs. My battery voltage will drop some underway but seems to come back up to a degree.
At the end of the day I’m concerned about the negative current number while running.
Here is a screenshot of the app
Should I continue to be concerned or is this expected. If not any ideas on what to check next? Thanks for any feedback.

Since you say this screen shot was underway, with the engine outputting 14.4 volts and your battery monitor seeing 12.91 volts, that says to me that when this screenshot was taken, the engine and house batteries were not connected (i.e. the ACR's were open).