feeding battery monitor with two battery banks

bukzin

I am ready to purchase a battery monitor ( Bogart Engineering TM-2025-RV) that I want to set up
to two banks of batteries in a large RV.

I have 4 six volt house batts and 2 twelve chassis batts.


I assume I need to shunts, correct?

Also would like to connect the new monitor to each bank to watch
amp-hours, current draw, etc.



What are my options here? What else might I consider?

Thanks!

BB.

Re: feeding battery monitor with two battery banks

Other options include--Some Battery Monitors include a second channel just for measuring voltage on the vehicle battery bank (no shunt support, for use on boats--such as the Victron and perhaps one of the Xantrex models).

Something else to think about--Next time you replace the vehicle battery bank--Look at two 6 volt batteries in series. By the way, is this a diesel vehicle with two batteries for cold starting? Deep Cycle batteries usually have be bit less cranking current, so (unless you are using AGM), you would need a bit more AH capacity to match a SLI type battery. Battery FAQ:

Using a deep cycle battery as a starting battery There is generally no problem with this, providing that allowance is made for the lower cranking amps compared to a similar size starting battery. As a general rule, if you are going to use a true deep cycle battery (such as the Concorde SunXtender) also as a starting battery, it should be oversized about 20% compared to the existing or recommended starting battery group size to get the same cranking amps. That is about the same as replacing a group 24 with a group 31. With modern engines with fuel injection and electronic ignition, it generally takes much less battery power to crank and start them, so raw cranking amps is less important than it used to be. On the other hand, many cars, boats, and RV's are more heavily loaded with power sucking "appliances", such as megawatt stereo systems etc. that are more suited for deep cycle batteries. We have used the Concorde SunXtender AGM batteries in some of our vehicles with no problems.
It will not hurt a deep cycle battery to be used as a starting battery, but for the same size battery they cannot supply as much cranking amps as a regular starting battery and is usually much more expensive.

Normally, for a SLI (starting, lighting, ignition) type battery, you don't want to cycle those much below 15% use (85% State of Charge)--They just will not have as long as life, and the vehicle charging system is not really configured to properly recharge a deep cycle battery (unless you convert over to a Balmar or similar alternator/charging system).

So, running a full battery monitor (with second current shunt) on the vehicle battery may be a bit on the "Overkill" side for instrumentation.

-Bill

bukzin

Re: feeding battery monitor with two battery banks

Thanks Bill,

A bit more info on my set-up...

Both my house and chassis banks are 12volt flooded batteries.

All seem to be in good shape so no change there for awhile.

This is a all stock 2006 Monaco class A coach that I plan on doing a lot of boondocking in.

willardj

Re: feeding battery monitor with two battery banks

I'll just say you can not go wrong with the Trimetric 2025 rv. We have had ours lil over a year now and can say that thing is awesome. It gives us all we could ask for as far as keeping up with our batts.

BB.

Re: feeding battery monitor with two battery banks

Clarify? Can or Can Not go wrong?

-Bill