Schweitzer Engineering Laboratories SEL-701, Instruction Manual

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701 Motor Protection Relay
Date Code 20010719
Modbus
®
RTU Communications Protocol
Reading Event Data Using Modbus
C.18
Reading Event Data Using Modbus
The Modbus Register Map provides a feature that allows you to download
complete event data via Modbus. The SEL-701 Relay stores the latest 14 full-length
event reports in nonvolatile memory.
Section 9: Event Analysis contains a complete
description of the event data.
Download event summary data by writing an event number to 0371h, then reading
the desired data from addresses 0372h through 0395h.
To download analog event data using Modbus, you need to select both the event
number (write to 03A1h) and the analog channel number (write to 03A2h), then read
the 4-sample per cycle event data from addresses 03A3h through 03DEh.
Table C.17
shows the channel assignments.
Table C.17 Assign Event Report Channel Using Address 0392h
Table C.17 Assign Event Report Channel Using Address 03A2h
Set 03A2h Equal To To Read Data From Channel
1 IA
2 IB
3 IC
4 IG
5 IN
6 VA
7 VB
8 VC
9 Relay Word Rows 1 & 2
10 Relay Word Rows 3 & 4
11 Relay Word Rows 5 & 6
12 Relay Word Rows 7 & 8
13 Relay Word Rows 9 & 10
14 Relay Word Row 11 & reserved