Battery monitoring question

[Sensfan]

Our 2012 RT 190 Ranger has a 12 volt outlet installed in the upper rear cabinet
on the passenger side for the TV and DVD player. Can this outlet be used to monitor our two 6 volt AGMs?

[booster]

Originally Posted by Sensfan

Our 2012 RT 190 Ranger has a 12 volt outlet installed in the upper rear cabinet
on the passenger side for the TV and DVD player. Can this outlet be used to monitor our two 6 volt AGMs?

It should be connected to the coach batteries and will go on and off with the "battery" switch on the control panel, so you would be able to read the coach battery voltage there, but not state of charge (accurately) or current draw.


The only way to really monitor the state of charge and currents is with a shunt based battery monitor like a Victron or Trimetric. IMO, all RVs should have them so you can know what is going on and how much capacity you have at any given time.

[Sensfan]

Originally Posted by booster

It should be connected to the coach batteries and will go on and off with the "battery" switch on the control panel, so you would be able to read the coach battery voltage there, but not state of charge (accurately) or current draw.

The only way to really monitor the state of charge and currents is with a shunt based battery monitor like a Victron or Trimetric. IMO, all RVs should have them so you can know what is going on and how much capacity you have at any given time.

Thanks Booster, you coached me on this subject a few years ago, however I did not followup with an install. Mobilife Kitchener will be putting in my preferred monitor this fall. As far as Roadtrek 190s are concerned, are there any mention-worthy pros or cons re Victron and Trimetric?

[booster]

Originally Posted by Sensfan

Thanks Booster, you coached me on this subject a few years ago, however I did not followup with an install. Mobilife Kitchener will be putting in my preferred monitor this fall. As far as Roadtrek 190s are concerned, are there any mention-worthy pros or cons re Victron and Trimetric?

Both are very good monitors. I prefer the Trimetric as it seemed to be easier to monitor all the stuff I wanted to get to more easily than a Victron would be, but others think the Victron is easier. Neither is a bad choice IMO.

[Sensfan]

Thanks again for the feedback ... and enjoy your Fourth of July 2023.

[Jim86301]

You might look at a PowerMon from Thornwave Labs. I used this battery monitor for several years and it has worked great!
Jim

[Sensfan]

Originally Posted by Jim86301

You might look at a PowerMon from Thornwave Labs. I used this battery monitor for several years and it has worked great!
Jim

Thanks Jim,
I was leaning toward having a Victron 712 installed; however, the two 6v AGMs in my 2012 190 Ranger are housed in a side compartment with no sliding drawer and are bolted inside a frame that is attached to the floor of the compartment. If the shunt attaches directly to the battery inside the compartment, my non-DIYer gut feel is that there may be insufficient room for the shunt addition. McGiver installations often work well, however they can introduce new unwanted risk. Are you familiar with the shunt size of the Victron 712 and, if yes, how does it compare in size to the PowerMon shunt?

[GeorgeRa]

If you have more access on the positive battery side a BlueSea 1830 can be your answer. It can be connected a positive side with some loss of accuracy.

https://www.bluesea.com/resources/686

"It is possible to connect the the DC shunt on the positive side of the circuit without a Shunt Shifter (for example on the output side of an alternator) however the measurements will only be accurate to +/- 4%, as opposed to +/-1% on the negative side."

[@Michael]

Originally Posted by Sensfan

Thanks Jim,
I was leaning toward having a Victron 712 installed; however, the two 6v AGMs in my 2012 190 Ranger are housed in a side compartment with no sliding drawer and are bolted inside a frame that is attached to the floor of the compartment. If the shunt attaches directly to the battery inside the compartment, my non-DIYer gut feel is that there may be insufficient room for the shunt addition.

You can (and should) mount the shunt someplace away from the battery terminal and run a short battery cable from the shunt to the battery negative.

Victron has dimensions drawing for all of their gear, so you can figure out if it'll fit someplace in the battery cabinet ahead of time.

[Sensfan]

Thanks guys. And per Michael's suggestion, I will review the Victron 712 installation data and measure the battery box dimensions to determine whether or not there appears to be sufficient space. I will then contact my RT technician for his input.

[Jim86301]

The PowerMon BT-DCPM (the model I have) has a built-in 60 amp shunt but can be used with any shunt up to 10,000 amps! I selected a 100 amp shunt which is adequate for my set-up. (The 5S model has a built-in 500 amp shunt.) For the best accuracy the shunt size should be selected to be close to (but above) the maximum expected current flow. From what I can tell the Victron 712 only comes with a 500 amp shunt. The shunt can be mounted anywhere reasonably close to the battery. The PowerMon devices can work with the shunt on either the negative or positive side of the batteries.