I have a Multiplus 12/1600/70 and am going to connect the second DC trickle charge outlet to my start battery. When the Multiplus is in Inverter or Charge mode I have 13.8 volts at the second DC output which is what I expected but with the Multiplus turned off I have the same voltage as my leisure batteries, if I isolate my leisure batteries the voltage drops to zero.
Does this mean that my started battery will drain my leisure batteries ? If so I will install a switch on the second DC feed to the started battery so at night time while parked up with no solar or grid power I can turn off the DC trickle charge from the Multiplus.