Voltage regulator

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So I have a similar setup in my Aircam with twin Rotax, two B&C regulators and an EarthX battery. One thing I notice is that the indicated voltage on my Dynon panel does not climb above 13.4-13.5V, I am used to the voltage climbing over 14V when I go fly with the old standard battery. Whether this has something to do with the electronic brain in the EarthX or not I do not know. EarthX say they like to see voltage over 14V so that the cells get balanced. I'm not sure if I have a problem or not. Batteries do not appear to be discharging during 1-2 hours of flying. Both alternators seem to be charging. Any ideas?

I had preset my voltage to around 14.2v by backing out the adjustment pot by 2 turns ( 0.1 volts per turn, decrease CCW).

On startup, voltage is below 14v until charge rate goes down to 1 amp or less, as the battery tops up, Voltage then slowly rises to 14.2 and stays there. 

I would say to adjust the voltage up, one at a time (disconnect other one temporarily) to desired level. One unknown is one regulator interfering with the other, not many twin Rotax installs out there. Worth dropping a question to B&C, they are great to work with.

Yes, I've been back and forth with B&C and EarthX, even the Optimate charger people. You could be right it could be a twin charging and regulator conflict issue. As I said it's not even clear I have a problem as the battery does not seem to be discharging over an hour plus of flying and both alternators appear to be working. Voltage just sticks at 13.4. It just seems to be something peculiar to having the EarthX,  as voltage climbed into the 14's with a standard battery. I've tried even adjusting the B&C's to 14.8 max with no change, and I have them now at 14.5. (1 turn over the standard setting) Maybe even something to do with the EarthX electronic control circuit. 

I use the Optimate charger and when I get back from flying and connect it, the charger drops 1 bar to it's balancing mode, which is what it is supposed to do and which it does if you even disconnect the charger for a short while and reconnect it.

I have installed an Edge Performance EFI so of course my battery is critical. I may just go back to an Odyssey battery for peace of mind, though I love the EarthX cranking power.

I've even thought of installing a backup EarthX, but maybe that's overkill.

Maybe you should try an Aerolithium battery.. same weight and cranking power.