Truck to camper wiring questions

It is important to have very little voltage drop between the camper batteries and the truck batteries. THe wires need to be big and the connections very good. Because the trucks voltage regulator senses battery voltage, and adjusts the alternators output accordingly. When the battery voltage is low, the regulator cranks up the alternators output to charge it. The truck battery is right next to the alternator, so the voltage regulator has a tendency to sense only the truck battery voltage, reducing the rate of charge below what is needed to charge the camper batts. A better connection from the camper batteries to the truck battery causes the regulator to sense their voltage and increase the alternator output.