I need some help. In this photo to the left you can see my PV wires running from my roof panels showing both positive and negative wires in red and black respectively. On the right you can see my leads from the other side of my van connected to my MPPT 1-5kva. Notice both wires are black. When I installed these wires, I taped the positive wire so I could tell which wire was positive on the end of the wires without terminals. I did not tape the positive wire on the other end as shown in the photo because they had terminals already attached. Now I'm not sure which is which and I need to put the correct connector terminals on the red and black wires. My question is: how do I determine which terminal goes on which wires? Can you tell from the connectors which is the positive wire? The wires are not labelled. I'm afraid I'll blow up the MPPT unit if I do it backwards. Can someone help me out?