IEC 60870-5-103 defines channels (analog data) and tags (digital data) to be transferred from a disturbance recorder file. The IEC 60870-5-103 file transfer is random access, meaning that the client can select exactly what information to read from the file.
The standard defines the identification, ACC (actual channel), for eight channels, numbered 1...8. For example, when a client requests channel 1, it always means Phase current L1. The IED supports all the eight IEC 60870-5-103 standard channel numbers and in addition defines some private channel numbers. Private channel numbers starts from ACC 64 as is defined by the standard.
| ACC Number | Signal |
|---|---|
| 1 | Phase current IL1-A |
| 2 | Phase current IL2-A |
| 3 | Phase current IL3-A |
| 4 | Neutral current Io-A |
| 5 | Phase voltage U1-A or phase-to-phase voltage U12-A |
| 6 | Phase voltage U2-A or phase-to-phase voltage U23-A |
| 7 | Phase voltage U3-A or phase-to-phase voltage U31-A |
| 8 | Neutral voltage Uo-A |
| Private channel numbers | |
| 64 | Neutral current Io-B |
| 65 | Phase current IL1-B |
| 66 | Phase current IL2-B |
| 67 | Phase current IL3-B |
| 68 | Neutral voltage Uo-B |
| 69 | Phase voltage U1-B or phase-to-phase voltage U12-B |
| 70 | Phase voltage U2-B or phase-to-phase voltage U23-B |
| 71 | Phase voltage U3-B or phase-to-phase voltage U31-B |
Disturbance recorder channels are the physical measurement inputs to the IED. It depends on the IED type if all the disturbance recorder channel signals are available or not. The IED may measure voltages either between phase and ground or between phases. The contents in ACC 5...8 and 69...71 are coupled directly to these voltage measurements.