Hikvision support emailed me:
"The PDF in your email is outdate. The DS-2DE7174-AE doesn’t support RS485.
We advise you the DS-2DE5120I/5220I-AE camera which can support the HIKVISION, Pelco-P, Pelco-D, self-adaptive RS-485 Protocols"
So even though you can find .pdf documents on the...