Readout mode¶
The device reads the energy meter periodically. Latest data is synchronized in the background (when a gateway is nearby) while the history of the most important data is stored in memory to be synchronized manually later.
Quick facts¶
| data set | ㉈ | power & energy OBIS codes (details) |
| period |  | 15 min / 1 min / live (details) |
| time drift | ➗ | 2s (assuming periodic synchronization) |
| duration |  | a few seconds, < 4s typically |
| attempts | 🔁 | 3 (within a few seconds interval) |
| interface | 🔌 | optical port or blinking diode (details) |
| protocol | 📜 | IEC 62056-21, SML, BLINK (details) |
Interface¶
The device utilizes the following ports of the meter:
optical port — it provides the most of reading data. In this case the device reads all the available information from the energy meter and forwards it to the cloud according to the processing policy.
blinking diode (so called control output / impulse output) — it allows you to track the power and energy usage in real time (Live mode). In this case it counts the blinks of the diode which correspond to the energy consumed from the grid. Note: this way you cannot track the energy returned to the grid.
The device can only be installed using one of the approaches at a time!
You cannot switch ports freely afterwards. If you want to install the device on the second port, you have to uninstall it first and then install again.
Timings¶
The device starts the reading sequence from the beginning of the next 15-min period in time after installation or synchronization after battery replacement. Example below.
Legend
□ (square) — moment of installation / synchronization after battery replacement
○ (circle) — moment of readout
Timings - 15 min period
Timings - 1 min period
Timings - live
The device installed on the blinking diode operates in live mode. It means the power chart on cloud is updated every few seconds (as conventionally shown in green in the figure below). Nevertheless, the device forwards to cloud the readings table according to the readout period which depends on the device configuration (See: Live mode).
Data truth¶
Data truth is guaranteed by an energy meter. The OneMeter device is not a meter (except you install it on blinking LED). Measurements are read from the meter directly during the readout.
Do not try to read data from the other meter than the one the device was installed on.
In case the meter was replaced by the energy operator or your willingness to move the device on another meter, uninstall it first.
Accuracy¶
Below is information about the accuracy of readings depending on the device firmware version.
The best accuracy is exclusive for OneMeter Enterprise.
The accuracy of data reading is up to two or three decimal places, or more precisely 0.01 or 0.001 of default unit for given quantity (for example 0.01 kWh or 0.001 kWh). The maximal value of the abacus is respectively 42 949 672.95 kWh and 4 294 967.295 kWh for given example. The use of higher data accuracy only makes sense if the meter provides data with no worse accuracy.
If the obtained value is too large (the information does not fit in 4 bytes), the value will overflow. To avoid this situation, meters usually allow setting a multiplier and using so-called transformers. In OneMeter Cloud, there is an option to include the multiplier when presenting results.
Data accuracy can be selected in the mobile app settings before installing your device and cannot be changed once installed. Greater accuracy may be applied depending on the type of service.
The use of higher data accuracy may (but does not have to) result in longer reading history synchronization and reducing Estimated device memory capacity.
The accuracy of data reading is to two decimal places, or more precisely to 0.01 of the default unit for the reading (for example 0.01 kWh). The maximal value of the abacus is 42 949 672.95 kWh for given example.
If the obtained value is too large (the information does not fit in 4 bytes), the value will overflow. To avoid this situation, meters usually allow setting a multiplier and using so-called transformers. In OneMeter Cloud, there is an option to include the multiplier when presenting results.
Features¶
DSR mode¶
This option is exclusive for OneMeter Enterprise.
The device is able to read data from the meter every 1 min and advertise it. Beware one-minute data will not be stored in the memory.
Note: The existing feature of 15-min readout and storage does not change.
Depending on the quality of communication between the device and the phone and server, there may be some gaps in one-minute data that will not be filled in the synchronization process with mobile application. Make sure that the gate has a stable internet connection and is located within range of the device.
This mode has a negative impact on battery life of the device.
Live mode¶
Need to install on blinking diode
In this mode the power chart on cloud is updated every few seconds. This vital feature allows you to understand the energy consumption profile of your installation depending on the devices turned on as well as to detect its errors or anomalies more easily.
The readings table will be updated on cloud with the readout period according to timings which depends on the device configuration. Energy returned to grid, tariff values, detailed power and energy information and meter identification data will not be available, because in this mode the device does not have a direct connection to the meter.
