Like the OP, I wanted to monitor the voltage of my batteries. I don't have a remote monitoring panel so I bought simple two-wire, 3 digit voltmeters on e-bay. Also bought the bezels for the units - got 3 displays and 5 bezels for under $10. Installed one set in the electrical compartment to monitor the converter output (it is next to my PI EMS-LCHW50). Installed the second unit in the dash to monitor the coach batteries. The dash mounted monitor has an added benefit of monitoring the BIRD functionality (including the alternator output). I agree it does't determine battery state of charge, but just knowing the alternator is charging the coach batteries while on the road gives me peace of mind. When the engine is off, the dash unit monitors the coach batteries and the converter output. I like knowing what's happening when the coach is in motion since DCV is important for the AC units, furnace, refeer, and the inverter. JM2¢...