VEGA VEGACOM 557 Profibus DP - Manual (Page 21)

VEGACOM 557 Profibus DP 21
Switch adjustments on VEGACOM 557
Hook switches additional board
The hook switches are used to switch on the
bus terminator resistors.
Switch positions
1 2
1 2
Hook switch closed:
Bus terminator "On"
Hook switch open:
Bus terminator "Off"
VEGACOM 557 PLC
Both hook switches are
closed
VEGACOM 557 VEGACOM 557 PLC
Both hook switches Both hook switches
closed open open closed
Example 1:
If a VEGACOM 557 is connected to a PLC,
both hook switches have to be closed (bus
terminator ON).
Example 2:
If several VEGACOM 557 are connected to a
PLC, both hook switches have to be closed
on VEGACOMs located at the beginning and
end of the connecting line, and open on
VEGACOM 557s located in between.