Can anyone please tell me what cable you use for any RS485 communication cable for outside use in a substation? I use to use Belden 9742 but it is not rated for moisture outside etc. Any help would be appreciated.
RS-485 isn't really too demanding in terms of the cable characteristics.
I think utilities prefer to run fiber inside substations these days for the inherent safety and noise immunity benefits over a copper connection. Having said that, we have used RS-485 fairly successfully in substations when fiber ports were not available.
We run RS-485 all over our distribution subs for SCADA. We use standard ethernet cable that we get in a great big roll box. It's buried in conduit though, so we don't have a weather hardened cable.