Digital OverVoltage Relay (GDR-C01) User's Manual V1.00
18 / 47
Kyongbo Electronics Co., Ltd.
4.2.1
RS-232C Communication
【
Figure 4.1
】
RS-232C Circuit Diagram
【
Figure 4.2
】
RS-232C Connection
Ÿ
The RS-232C communication cable supplied with this product uses a cross
cable which has No. 2 and No. 3 pins crossed ash shown in
【
Figure 4.1
】
,
so using ordinary direct cable will not enable the communication.
Ÿ
If there is no RS-232C port in the PC, and uses USB port, only with
USB to 232 cable cannot make connection, so plesae use USB to 232
cable with the cross cable supplied with this product together.
4.2.2
RS-485C Communication
To connect to higher level monitoring control system, insulated RS-485 Half Duplex
communication method is provided. This communication method can connect with
multi-drop, and the maximum communication distance is 1.2km. The end part of
RS-485C cable should be connected with 120Ω resistor parallel as shown in the
following figure..
【
Figure 4.3
】
RS-485C Connection Diagram
