Yaskawa MP920 Communications Module - Manual (Page 307)

D.2 Indoor Panel-to-Panel Wiring
D-15
D
„ 217IF RS-485 Panel-to-Panel Cable Connections
The following figure shows a 217IF RS-485 panel-to-panel cable connection example.
Fig. D.10 217IF RS-485 Panel-to-Panel Cable Connection Example
• Connecting Signal Lines
Use panel-to-panel cables to connect the incoming and outgoing SRD+ and SRD- signal
terminals on each control panel as shown in the above figure.
• Connecting Terminating Resistances
Mount terminating resistances at both ends of the transmission line.
• Connecting Shielded Ground Trunk Cables
Connect the shield of each panel-to-panel cable to shielded wire junction terminal S on
each control panel and ground it at one point only.
Using a ground wire of 8 mm
2
or greater, ground the shield to an independent ground
pole with a ground resistance of 100 Ω or less.
120 Ω
+ -
SRD S
+ - + -
SRD SRD S
+ -
SRD S
E
120 Ω
8 mm 2
Independent ground
pole: 100
Ω or less
S
Panel-to-panel
cable