Schweitzer Engineering Laboratories SEL-421-4, Instruction Manual

Page: 1310 / 1518

15.40
SEL-400 Series Relays Instruction Manual Date Code 20171006
Communications Interfaces
Direct Networking Example
To view the temperature measurements received from the SEL-2600A, issue the
MET T command, as depicted in Figure 15.8 .
NOTE:
In some SEL-400 series
relays, you must use MET RTD instead
of MET T.
The MET T command displays the following messages:
➤
Channel Failure
: This message is displayed for each channel whose
channel status bit is not asserted.
➤
Channel Not Used
: This message is displayed for each channel
whose channel type is set to NA.
When there is a status problem with the SEL-2600A RTD module, the MET T
command will respond with an informational message, as shown in Figure 15.9 .
The four possible messages for status problems, with their interpretation, are
indicated in
Table 15.30 .
Direct Networking Example
This direct networking example demonstrates direct networking to the relay
using the Ethernet card.
Figure 15.10 shows the Ethernet network topology. This
examples uses a SEL-421, but the same concepts apply to any SEL-400 series
relay.
=>> MET T <Enter>
Relay 1 Date: 05/17/2003 Time: 13:42:13.220
Station A Serial Number: 0000000000
RTD Input Temperature Data (deg. C)
RTD 1 = -48
RTD 2 = Channel Failure
RTD 3 = 0
RTD 4 = 24
RTD 5 = Channel Not Used
RTD 6 = 72
RTD 7 = Channel Failure
RTD 8 = 120
RTD 9 = Channel Not Used
RTD 10 = 168
RTD 11 = 192
RTD 12 = 216
Figure 15.8 MET T Command Response
=>>MET T
SEL-2600 Failure
Figure 15.9 MET T Command Response for Status Problem
Table 15.30 MET T Command Status Messages
Message Interpretation
SEL-2600 Failure RTDFL status bit asserted
Communication Failure RTDCOMF status bit asserted
No data available Port Protocol not set to RTD
Channel Failure RTD xx ST status bit deasserted