There have been many threads dealing with the issue of battery management in the New Aire. While I am not an expert in this area, I thought it would be helpful to share my views about this issue. Since I don't have complete schematic diagrams for the New Aire, my comments here reflect my best effort to reverse engineer the electrical systems in this coach as a basis to reflect on options to better manage the batteries in the coach. Much of this discussion will apply to other SilverLeaf coaches. The KA with dual inverters may be the exception.
The New Aire has two battery systems: eight AGM coach batteries and two chassis batteries. These two system are interconnected by a charge bridge solenoid. This solenoid is controlled by the TM102 SilverLeaf module which open and closes the relay under certain circumstances to link the two battery systems. The charge bridge solenoid can be opened and closed manually by using the "Battery Boost" switch in the cockpit. To the best of my knowledge there are no other connections between the coach and chassis electrical systems.
In those coaches equipped with solar panels and a solar controller the Newmar implementation of SilverLead does not recognize the presence of the solar controller to open and close the charge bridge solenoid. As a result even when full charge is being applied to the coach batteries by a solar controller, no connection is made to the chassis battery thus this battery system is not charged during solar charge operations.
In order to properly monitor and manage any battery system you need to be able to sample voltage and current going and coming from the battery. The standard New Aire electrical system does not have a battery monitor system associated with either the coach or chassis battery system. There is a shunt in the Xantrex inverter/charger that monitors voltage and current through this unit. This is the information displayed on the New Aire SilverLeaf panel. The panel also displays the current voltage associated with the chassis battery.
It is important to understand the SilverLeaf monitor is displaying the current passing in/out of the Xantrex charger/inverter, not the current flowing into or out of the coach battery. The only way to under to get information related to current flow into and out of the coach (or chassis) battery is through the use of a battery monitor system equipped with a shunt immediately attached to the battery.
The best way to understand all this is to look at all the information displayed by both the SilverLeaf system and a battery management system attached to the coach battery. Below you will see a series of screen shots taken within a few seconds of each other in my NA today. My NA has been in an outside storage lot for the last two weeks. The coach is equipped with 1 kW of solar power previously documented in other posts.
Here is the home page of the SilverLeaf display panel. The house battery and the chassis battery current voltage is 13.7. When I store my NA outside, without shore power, I keep the "Battery Boost" switch on closing the charge bridge solenoid. This allows the solar controller to manage the battery charge schedule for both the chassis and house battery. You will also notice the Inverter is on supplying 118V @ 2A to the inverter circuits. The refrigerator was running when this images was taken.
The second image below shows the "AC Power" page on the SilverLeaf display it repeats the same AC power information displayed on the home page.
The image below displays the "DC Power" page on the SilverLeaf monitor. Note this image depicts the house battery at 71F, 13.8 volts, passing 15 amps to the inverter. Those 15 amps of DC power are being used by the inverter to generate 2 amps of AC power at 118 volts. The key here is that those 15 amps of DC power is not the only load going or coming from the house battery (or solar panels if equipped). It is
only the load going to the inverter.
The next image below shows the status of the solar charge controller. You can see the solar panels in this image are generating 444 watts. The solar controller is passing that energy to the coach electrical system at 13.89 volts and 31.2 amps. Notice that this current flow is much higher than the 15 amps shown above on the SilverLeaf panel going to the inverter. The difference between the current flows is related to the current flowing to other DC sources in the coach (including chassis battery) and the current flowing to coach batteries being charged in "Float".
The next image shows the output from the Victron BMS. This is the device that gives you definitive information about the state of the coach batteries. There is no other way to know your current coach battery SOC (state of charge) without a battery management system such as the Victron BMS. You can see the BMS has calculated that the coach batteries at at 100% of charge. Also note that the batteries are taking in 5.0 amps of current which is the "Float" charge going on to maintain the batteries at 100% until sunset.
So putting this all together, when these images were shot, the sun was supplying the coach with 31.2 amps of power. The coach batteries were using 5.0 amps for "Float maintenance", the inverter was using 15 amps for generating 118 volts @ 2 amps of AC power and the coach/chassis battery was consuming 11.2 amps to run DC sources and charge the chassis battery in float via the charge bridge relay.
I know this can be very confusing to sort out for a newbie, thus the post. The important thing to remember is that SilverLeaf is not giving you the full story with regard to current battery state.
Do not rely on it for battery management.
The New Aire is a high tech, all electric coach. To be useful in all phases of operation (camping, storage and service) an owner needs the right tools to properly operate the coach. The New Aire as delivered (without the solar panel option) is missing two very important items: solar panels and a battery monitor system.
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