??? 12/16/11 08:38 Read: times |
#185115 - Cable length Responding to: ???'s previous message |
I used CAT5 cable to power up my clocks, used 2 lines for RS422 and wired the rest for power 3 parallel for gnd and other 3 parallel for + to reduce the total wire resistance. What I noticed is that there is a voltage drop across the wires as length increase and now I realise why they make the voltage 48vdc in POE.
My power supply was 12vdc 3A and it goes down to 7VDC on the next clock 20 meters away. Each clock consumes less than 300mA at 5VDC. Mahmood |