Features Two photoelectric isolation RS485 interfaces Suitable for ring network Description P-9940A is an optional card for GST200 series control panels, providing two photoelectric isolation RS485 interfaces. This card shouldn’t be inserted and removed when it is energized. When entering calibration mode, pressing SK1 key (reset main board), it will display Color CRT OK if registration is successful. LEDs: 1）Main board communication HL1 LED: Red. It flashes when communicates with main board normally. 2）Master Interface（A1B1）communication HL2 LED: Green. It illuminates steadily when RS485 master interface is in normal communication and there is no message transmitting on the loop. 3）Slave Interface 2（A2B2）communication HL3 LED: Green. It illuminates steadily when RS485 master interface is in normal communication and there is no message transmitting on the loop. In the network made of those cards, A1B1 connects with the A2B2 of the neighbor control panel. Each of RS485 loop shouldn’t exceed 1200m in all, supporting the network of maximum 32 GST series control panels.
