Horner APG QX751 OCS User Manual

Page 4

MAN0889-03-EN

Specifications / Installation

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11/20/2009 Page 4

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Figure 6 – Port 3 (CN1) RS-485 Port

3.3.3

DIP-Switch

The DIP switch is used for setting the terminating resistance of the RS-485 signal line at the CN1, MJ1, or MJ2 connector.

Figure 7 – DIP Switch

(1)

Set DIPSW 8 to ON position when termination is required on MJ2.

(2)

Set DIPSW 7 at the terminating station of the QX751 units to the ON position when connecting PLCs through RS-422/485.

(3)

Set DIPSW 6 to ON position when termination is required on MJ1.

(4)

Set DIPSW 5 to the ON position to add a terminating signal to SD when connecting through RS-422/485.

(5)

DIPSW 1, 2, 3 and 4 are for future use, keep these in OFF position.

Shielded Cable

Send Data (-)

To RS-485 Port

Send Data (+)

Receive Data (-)

Receive Data (+)

-SD

Port 3

+SD

-RD

+RD

Signal Pin No.

Shielded Cable

Receive Data

Send Data

To RS-232 Port

Port 3

Signal Pin No.

Figure 5 – Port 3 (CN1) RS-232 Port