Connections; Wiring Guidelines - Siemens Milltronics BW500 Operating Instructions Manual

Communications

11.2 Connections

11.2 Connections
When a SmartLinx card is installed and P799 = 1, the parameters that the SmartLinx card
is writing to the BW500 and BW500/L will be continuously updated. Therefore, if you
connect a SmartLinx card to the BW500, set P799 = 1 and not write anything to the
SmartLinx card, your setpoints will be 0.
There are three serial communication ports on the BW500 and BW500/L:
Refer to the Installation (Page 21) for wiring diagrams specific to each port.
11.2.1

Wiring Guidelines

Improper wiring and choice of cables are the most common sources of communication
problems. Listed below are some suggested guidelines:
• 15 meters (50 feet) for RS-232
• 1200 meters (4000 feet) for RS-485
• Ensure that communication cable is run separately from power and control cables (i.e. do not
tie wrap your RS-232 cable to the power cable or have them in the same conduit).
• cable is shielded and connected to ground at one end only
• 24 AWG (minimum)
• follow proper grounding guidelines for all devices on the bus
• use good quality communication grade (shielded twisted pairs) cable that is recommended for
RS-232.
126
WARNING
Port
1
2
3
Description
RS-232, Terminals 31 to 34
RS-485, terminals 35 to 40
RS-232, RJ-11 modular telephone jack
BW500 and BW500/L
Operating Instructions, 12/2016, A5E33482052-AD