Alstom MiCOM P846, Technical Manual

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Firmware Design P846/EN FD/D
MiCOM P846
(FD) 9-9
FD
1.3.5.2
h normally open contacts and two with
changeover contacts. The relays are driven from the 22V power supply line. The relays’
read from using the parallel data bus.
1.3.5.3
fitted to provide an accurate timing
reference for the relay. This can be used wherever an IRIG-B signal is available. The
s connected to the board via a BNC connector on the back of the relay. The
1.3.5.4
r or DNP3.0 protocol on the first rear communications port there is the
hardware option of a second rear communications port, which will run the Courier language.
hysical links: twisted pair K-Bus (non-polarity sensitive),
ut of the second rear
The power supply board incorporates inrush current limiting. This limits the peak inrush
current, during energization, to approximately 10A.
Output relay board
The output relay board holds eight relays, six wit
state is written to or
Depending on the relay model, up to three output relay boards may be fitted to the P846
relay to provide a total number of 32 relay outputs.
IRIG-B board
The IRIG-B board is an order option that can be
IRIG-B signal i
timing information is used to synchronize the relay’s internal real-time clock to an accuracy of
1ms. The internal clock is then used for the time tagging of the event, fault maintenance and
disturbance records.
The IRIG-B board can also be specified with a fiber optic transmitter/receiver that can be
used for the rear communication port instead of the EIA(RS)485 electrical connection
(Courier or DNP3.0).
Second rear communications board
For relays with Courie
This can be used over one of three p
twisted pair EIA(RS)485 (connection polarity sensitive) or EIA(RS)232.
The second rear comms. board and IRIG-B board are mutually exclusive since they use the
same hardware slot. For this reason two versions of second rear comms. board are
available; one with an IRIG-B input and one without. The physical layo
comms. board is shown in Figure 3.