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Default settings
9
5
ekr 500 web guiding controller
EDV No.: MD.299.01.06
Chapter: 9
with removable control panel
Date:
29.07.08
Page:
77/86
9.2 Keyboard
bus
terminating resistors
The internal terminating resistors of the controller and control panel
are switched on in the factory.
The settings usually do not have to be modified.
Check the terminating resistor settings if faulty operation or non-
defined controller or control panel processes occur.
9.2.1 Controller terminating
resistor
The controller’s internal terminating resistor can be switched on or
off using switch
S3
on the processor board.
The terminating resistor should only be switched
off after first obtaining agreement from the
manufacturer!
Switch
S3
Function
OFF
Internal terminating resistor switched off
ON
Internal terminating resistor switched on
(default setting)
Danger from mains voltage!
Never open the controller
before switching off the
mains!
Setting up the terminating resistor:
1. Switch off controller line voltage.
2. Open the controller enclosure cover.
3. Check switch
S3
setting on the processor board.
The switch
S3
must be set to the “
ON
“ position.
4. Switch
S3
to the “
ON
“ position if necessary.
5. Close the controller enclosure cover.
6. Switch on controller line voltage again.
Switch S3
O
FF
O
N