Why does the KDR-510 datalink receiver use two input wires for power and
two for ground? The schematic looks like this

KDR-510
3A
10-30 VDC---()-------------Power positive 1
\------------Power positive 2


Ground-------------|-------Power ground 1
|-------Power ground 2


Is the power positive 2 and power ground 2 wires just for redundancy?
I've never seen any avionics that use two wires both for power and ground.
Do both 1 and 2 need to be hooked up or just power and ground 1?