paulga, I think you are confused. The Genasun GV-10 (a solar panel charge controller) is the black box with white lettering on it thats about 3" tall and 5" wide. On its left side are 2 pairs of say 10 ga. conductors, red & yellow plus red & black. One of these pairs goes to one of your Battery Banks, the other pair goes to the solar panels. There should be fuses and or switches along the way.
Directly below the GV-10 is an Automatic Charging Rely, the 3" square black box with the 2 yellow tabs, which if you push them sideways allows you to take the cover off that exposes the large terminals. This ACR is nothing more than a fully automatic, voltage triggered switch that "closes" when either of these large terminals has a voltage greater than 13.0 +/- volts on it. The switch will also "open" when the voltage drops to something around 12.7 +/- volts. The ACR is constantly measuring the voltage and acts accordingly, it's automatic, you do nothing.
These ACRs are useful, here are a couple of examples.
- You have been on the hook overnight, watched a movie, with popcorn and now have made breakfast and coffee, all without running the genset. The house bank is depleted. You weigh anchor and get underway and 5 minutes later the alternator which is connected only to the start bank has raised the start bank's voltage to 13.1 Volts and bingo, the ACR "closes" which now connects the house bank to the start bank and naturally, the alternator and now you charge the house bank. Hopefully the alternator can handle the heat.
- After cruising for 5 hours to your next destination the house and start banks are both fully charged and the alternator is basically idling along, just producing whatever your running loads are, plus Metallica on the stereo. You drop the hook and shut things down, except Metallica. 5 minutes later the ACR "opens" as battery voltage dropped to the trigger voltage, which now isolates the start bank from the house bank as you don't want to deplete your start bank, unless it Mozart. In the morning, the start bank which is no longer connected to the house bank should easily start the engine.
Now to answer your question, jumping the 2 studs is likely the cheapest and most effective way of directing a charge voltage to both battery Banks. The problem is that you don't always want the two Banks combined as Metallica, while at rest, will certainly deplete the Start Bank. You would have to crawl down there and un-jump the Banks asap, should you want to start the engine in the morning. The ACR does this for you automatically.
The ACR monitors battery voltage, it does not know (or care) where the charge voltage came from. That being the case it will also combine the 2 Battery Banks (which effectively allows both Banks to charge) once one of them has it's voltage raised by the ac powered battery charger, your solar panels output, or the dynamo on your pedal bike.
As always there are lots of rules when using an ACR, you should do some reading.