protocol only. Courier is a proprietary communication protocol to allow communication with a range of
protection equipment, and between the device and the Windows-based support software package.
You can connect the unit to a PC with an EIA(RS)232 serial cable up to 15 m in length.
The inactivity timer for the front port is set to 15 minutes. This controls how long the unit maintains its level of
password access on the front port. If no messages are received on the front port for 15 minutes, any
password access level that has been enabled is cancelled.
Note:
The front serial port does not support automatic extraction of event and disturbance records, although this data can
be accessed manually.
4.1.4.1 FRONT SERIAL PORT (SK1) CONNECTIONS
The port pin-out follows the standard for Data Communication Equipment (DCE) device with the following pin
connections on a 9-pin connector.
Pin number Description
2 Tx Transmit data
3 Rx Receive data
5 0 V Zero volts common
You must use the correct serial cable, or the communication will not work. A straight-through serial cable is
required, connecting pin 2 to pin 2, pin 3 to pin 3, and pin 5 to pin 5.
Once the physical connection from the unit to the PC is made, the PC’s communication settings must be set
to match those of the IED. The following table shows the unit’s communication settings for the front port.
Protocol Courier
Baud rate 19,200 bps
Courier address 1
Message format 11 bit - 1 start bit, 8 data bits, 1 parity bit (even parity), 1 stop bit
4.1.5 FRONT PARALLEL PORT (SK2)
The front parallel port uses a 25 pin D-type connector. It is used for commissioning, downloading firmware
updates and menu text editing.
4.1.6 FIXED FUNCTION LEDS
Four fixed-function LEDs on the left-hand side of the front panel indicate the following conditions.
● Trip (Red) switches ON when the IED issues a trip signal. It is reset when the associated fault record
is cleared from the front display. Also the trip LED can be configured as self-resetting.
● Alarm (Yellow) flashes when the IED registers an alarm. This may be triggered by a fault, event or
maintenance record. The LED flashes until the alarms have been accepted (read), then changes to
constantly ON. When the alarms are cleared, the LED switches OFF.
● Out of service (Yellow) is ON when the IED's protection is unavailable.
● Healthy (Green) is ON when the IED is in correct working order, and should be ON at all times. It goes
OFF if the unit’s self-tests show there is an error in the hardware or software. The state of the healthy
LED is reflected by the watchdog contacts at the back of the unit.
MiCOM P747 Chapter 3 - Hardware Design
P747-TM-EN-1 31
To Next Page
Loading...
Need help?
General
