House Battery Run Time

[Jon Wehrenberg]

It sounds like whoever designed or installed the gauges forgot to consider there was a second inverter drawing from the same set of batteries. Ask for a refund on that feature.

[JIM KELLER]

Charles, What Mike said might help you better understand the set up of our Buses. When reading the soft tab panels one is showing the primary inverter and the other one is reading the secondary inverter.

[Jon Wehrenberg]

How do you know which is primary or secondary? On my coach which may have the same inverters the CC has, the roles of the inverters switches. Theoretically they are supposed to be identical, but one becomes the dominant one until the batteries need a greater charge in which case they both are working, but by turning the "primary" one off for a while I can reverse their roles. This only applies to charging. When the inverters are producing 120 volt power they can only supply power to their specific circuits which are hard wired. In that case there is no dominant or primary inverter. Actually when acting as chargers (in the presence of 120 volt input to the coach) those circuits powered by inverters still go through the inverters, but only a relay so they just function as devices through which shore or generator power passes through.

[truk4u]

With my RG7's, the primary remote will show for example, absorption charge, while the secondary I use as a fuel gauge will remain on float. This seems to indicate the primary is doing the charging while the secondary (fuel gauge) is idle. Not trying to make this inverter thing more complicated, but it would be nice to completely understand the functions, which are probably different for each brand inverter/remote.

[Jon Wehrenberg]

I think which inverter tends to carry the charging load relates directly to the accuracy of its internal circuit which senses voltage and the quality of the cables and terminals which carry battery power to the inverter. Due to those variables one inverter is going to sense the need for a specific charge before the other, and once it does it will begin charging as required and the second will not read a voltage on the battery bank which indicates it needs to start charging.

If the batteries are deeply discharged I would bet both inverters will be functioning as chargers and would be in bulk or absorbtion mode. Part of what influences this may also be as subtle as if the length of cabling is longer on one run to an inverter than the other, or if the converter has separated the batteries into two separate banks for purposes of having dedicated 12 volt circuits. On my coach I have 12 and 24 volt circuits and I believe they are split into two of each. (That is a guess. I have to look to confirm.)

[mike kerley]

Charles, compare the run time indications to your computer when copying files. It will go from 30 minutes to 2 minutes back to 40 minutes time remaining in seconds. Its looking at the file its copying and guessing what size the balance of the files are which changes with every file. Much like the inverter load, it changes everytime a new load comes on or increases its draw or, turns off. I doubt a circuit could accuratly predict the "run time" for a bus. Just to many variables. Would be best to only display that feature (useless as it is) on one control panel, and leave the other one blank.

It is possible to have just one Inverter charging, then kick in the second to increase the charge rate on the same set of batteries (dc voltage/current). This is tougher to do with an ac circuit as you would have to sync the flow from the two inverters before allowing them to feed the same load, so they just split the circuits between the two inverters for ac. At least, thats my opinion.

[gmcbuffalo]

Tom with your RG7 can you choose which inverter is pri and sec by pushing buttons or is an automatic feature?

[truk4u]

Greg,

You setup the primary as "shunt, other inverter and then the secondary as "shunt, this inverter."

[Jon Wehrenberg]

Why do you want to select one over the other as primary? In inverter mode each inverter powers only its dedicated circuits. In charger mode won't either inverter work as a charger and assuming this is so won't they sort out which assumes the charging load automatically? My RH inverter now carries the bulk of the load when charging, but if the DC load ramps up the second inverter steps in and helps with the charging.

[truk4u]

It doesn't disable the functions, it merely makes one remote a gauge that you can set to continually scroll through the parameters or a single function you want to monitor such as battery voltage. The primary also controls the gen auto-start.