Configuring The Modules - Sartorius YDO01SW-232 Mode D'emploi

8

Configuring the Modules

YDO01M-485/422 (Options A2 and A3)
Equipment supplied:
– Interface module
– 3 PCB mountings
– Installation instructions (this manual)
Interface module YDO01SW-485/422 (serial RS-485/RS-422 interface, electrically
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isolated ) can either be operated in RS-485 or RS-422 mode.
Configuration for intended use is implemented using eight switches.
Configure for intended use as an RS-485 or RS-422 interface, depending on the area
of application (network or point-to-point connection), requires the activation or deacti-
vation of the terminating resistors (120 O) and the bias resistors located on the board.
The switch arrangement is displayed in the drawing on the left. When switch 1 – 4 is
closed, the interface is configured for RS-422 operation.
The following functions are available when the relevant switch is closed (setting: "ON"):
Function (ON = closed)
Terminating resistor, transmitting side 120 O
BIAS resistor, transmitting side (TxD+, pull-up) 680 O
BIAS resistor, transmitting side (TxD–, pull-down) 680 O
ON: RS-422 operation | open: RS-485 operation
Terminating resistor, receiving side 120 O
BIAS resistor, receiving side (RxD+, Pull-Up) 680 O
BIAS resistor, receiving side (RxD–, Pull-Down) 680 O
No function
!
Note on setting the switches:
Switches must be set pairwise as follows:
– Switches 1–2 and 1–3: both ON or both OFF
– Switches 2–2 and 2–3: both ON or both OFF
Operation as an RS-485 interface (Option A3):
§ Switch 1 – 4 must be open in order to switch to RS-485 operation (factory setting).
$ Where applicable, deactivate bias resistors for RS-485 operation. Open switches for this
purpose (factory setting).
There must only be one instance of bias resistors per transmission path (network
or point-to-point connection). Otherwise there is a danger of transmission errors.
Where applicable, refer to the specifications or circuit documentation for the remote
station or network nodes in question. Bias resistors are always to be activated or
deactivated in pairs.
§ The terminating resistor (transmitting side, switch 1 – 1) must be activated if the device is
located at either end of an RS-485 bus system, or where it is connected to another device
in a point-to-point link. There must also be a terminating resistor of 120 O in place at
the remote station. Where applicable, activate terminating resistor (120 O) for RS-485
operation:
Close switches 1 – 1 ("ON" setting)
Operation as an RS-422 interface (Option A2):
§ Close switch 1 – 4 in order to switch to RS-422 operation ("ON" setting)
$ Where applicable, deactivate bias resistors for RS-422 operation. Set the switches to the
open position for this purpose.
§ Activate the receiving side terminating resistor (switch 2 – 1), if no external terminating
resistor is in place. Always deactivate TX terminating resistors (switch 1 – 1).
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) The shielding of the connecting cable is connected to the housing of the indicator at one end.
The indicator is connected to the protective grounding conductor.
Switch
1 – 1
1 – 2
1 – 3
1 – 4
2 – 1
2 – 2
2 – 3
2 – 4