I have installed BMV 712 with a 420 Ah house battery bank and a 55Ah starter/Aux battery. Everything appears okay except one read-out which I do not understand: looking at the display modes, when I come to the "Time-to-go" display I get the mid-point characters (as shown on p.5 of the manual, under 1.2 b), instead of getting any kind of number as shown on p. 8. What am I missing or not understanding?