The HDS 12 Gen 2 and Gen 3 units have a published power consumption of 26 Watts, or 2.0 Amps at 13.8V DC. With respect to an earlier comment you mentioned on current drain: Yes, as the supply voltage drops, the amperage draw will increase - to keep that same 26 Watts of power supplied to the unit. (Watts = Voltage x Amperage)

Low power standby is published for the Gen 3 as less than 650 mA, or 0.650 Amps. There is no published low power data for the Gen 2, but I'd bet it's similar to the Gen 3.

Thanks amigo, the ionic dealer confirmed that the app will show how many amps each device is drawing. I’ll post back next week with the results.

I'm sorry to inform you the Ionic dealer doesn't know what he's talking about as there is no way the app can give you the amperage for each device. To the battery, current simply leaves the battery via the terminal. Without individual terminals on the battery for each device, there's no way the battery can tell which electrons are going to which device in your wiring harness. Maybe they meant to say the app will tell you the load on the battery (in amps) at any given moment. If all the devices are on, then it will be the amps drawn by all of them. Of course, as you stated earlier, you can selectively turn on devices. What we don't know is the accuracy of the current measurement being reported to the app by the BMS inside the battery.