Why a load profile in the meter?
The load profile shows when load peaks occur, how a consumer behaves over the day and when the photovoltaic system feeds into the grid. That is the basis for analysing power peaks, for allocating energy among tenants and for energy management to ISO 50001.
If the load profile is stored in the meter itself, no values are lost when the network, gateway or control system fails. As soon as the connection is back, the target system fetches the missing entries.
Memory and interval
| Property | Value |
|---|---|
| Entries in the load profile memory | 105,378, about 3 years at 15 minutes |
| Interval | 1, 5, 15 (factory setting), 30 minutes, 1, 6, 12 or 24 hours |
| Entries in the logbook | 2048 |
| Load profile active by default | on the TCP/IP and LoRa versions |
When the memory is full, the meter deletes the 26 oldest entries at a time. The index keeps counting, so every entry stays unique. A shorter interval shortens the period accordingly: at 5 minutes the memory lasts about one year.
What an entry contains
When reading via TCP/IP, the meter delivers these columns per entry:
| Columns | Content | Resolution |
|---|---|---|
| 1–4 | Timestamp (UTC), index, status, serial number | |
| 5–8 | Active energy import and export, tariff 1 and 2 | 1 Wh |
| 9–12 | Reactive energy import and export, tariff 1 and 2 | 1 varh |
| 13–16 | Power total and per phase | 1 W |
| 17–21 | Current total, per phase and neutral | 1 mA |
| 22–24 | Voltage L1-N, L2-N, L3-N | 0,1 V |
| 25–27 | Power factor per phase | 0,01 |
| 28 | Frequency | 0,1 Hz |
The status is bit-coded and shows, for example, whether the time was changed during the interval. This makes it traceable why a value deviates from the grid.
Three ways to read the load profile
TCP/IP: directly via HTTP
The TCP/IP version returns the load profile via a simple address. Without parameters you get the last 3000 entries; that is the maximum per request. With last, from and to you limit the range by index:
http://<meter IP>/data/
http://<meter IP>/data/?last=1250
http://<meter IP>/data/?from=50&to=500M-Bus: via the M-Center
The EMU M-Center also reads the load profile memory of the Professional II. It reads new meters completely once, about 8 days of load profile per hour and meter at a 15-minute interval. The M-Center synchronises the meters’ clocks via M-Bus and therefore needs the correct time itself, ideally via NTP.
LoRa: by radio
The LoRa version sends its values from the load profile memory. By default, a packet with active energy import and export in tariff 1 and 2 arrives every 15 minutes. Which values are sent at which interval can be changed by downlink. Details on the LoRa page.
Order numbers
| Version | Article number | Shop |
|---|---|---|
| EMU Professional II 3/100 TCP/IP – direct connection 100 A | P20A000T | Shop: EMU Professional II 3/100 TCP/IP P20A000T → |
| EMU Professional II 3/5 TCP/IP – CT connection | P21A000T | Shop: EMU Professional II 3/5 TCP/IP P21A000T → |
| EMU Professional II 3/100 M-Bus – direct connection 100 A | P20A000M | Shop: EMU Professional II 3/100 M-Bus P20A000M → |
| EMU Professional II 3/5 M-Bus – CT connection | P21A000M | Shop: EMU Professional II 3/5 M-Bus P21A000M → |
| EMU Professional II 3/100 LoRa – direct connection 100 A | P20A000LO | Shop: EMU Professional II 3/100 LoRa P20A000LO → |
| EMU Professional II 3/5 LoRa – CT connection | P21A000LO | Shop: EMU Professional II 3/5 LoRa P21A000LO → |
Order online in the EMU Metering shop.