RLE FMS V.1.13 - Manual (Page 157)

rletech.com FMS User Guide 157
4 Advanced Communications - Modbus, BACnet, and Telnet
4.8. Telnet
The FMS supports a Telnet connection over IP port 23. When properly configured a Telnet
user can use the Com1 port of the FMS to communicate to external EIA-232 enabled devices.
4.8.1 Hardware Connections
The Com1 port is located on the back of the FMS. The COM1 Transmit and Receive LEDs are
also located on the back of the FMS.
The EIA-232 port allows communications between the FMS and one other device (point-to-
point connection). The EIA-232 port has maximum cable length of 50 feet (15.2m).
Figure 4.19 FMS Connection to an EIA-232 Device
Connect a nine-pin, straight-through serial cable to the FMS and to the other device.
Once you connect the serial cable, the FMS automatically switches to EIA-232 mode.
Pin Description
Pin 1 Data Carrier Detect
Pin 2 Receive Data
Pin 3 Transmit Data
Pin 4 Data Terminal Ready
Pin 5 Signal Ground
Pin 6 No Connection
Pin 7 Request to Send (internally connected to Pin 8)
Pin 8 Clear to Send (internally connected to Pin 7)
Pin 9 No Connection
Table 4.13 COM1 DB9 Male Pin Out