eMon Energy Monitor Service

This tutorial assumes you have started your subscription and received the confirmation email with username, password and database name.

Configure the service

To configure the eMon Energy Monitor Service data upload in eMon Energy, Hover over **Setup button** and click **Web Server** from the dropdown menu.

**Setup Menu**

Choose eMonIndonesia.

**Select eMon Service**

Here you specify what you want eMon Energy to upload to the service.

**Select eMon Service**
database

Name of the database that you received in your confirmation email.

username/password

Username and Password that you received in your confirmation email.

tag-set

tag-set

Usually users leave the tag-set configuration blank. A collection of user specified tag-key/tag-value pairs that will be included as part of each measurement will give the user more possibilities. The influx documentation somewhat explains them: https://docs.influxdata.com/influxdb/v1.7/concepts/key_concepts/#tag-key Basically, these tags each produce a table index that can be helpful in increasing the performance of data retrieval. The first tag-set is a special case for eMon Energy, and if specified, is used to uniquely identify the measurement subset from this device so that upload can resume seamlessly. If this is not the only device that will be posting to the database, a unique identifier for this device should be included as the first entry in a tag-set. tag-values can be a constant string or can include variables as explained below under variables

edit an existing tag by clicking on it's associated edit button, or add a new one with the add button. add tag-set

**Influx tag-set**
field-key

Each measurement contains a field key and field value. The field value is always the value specified in the "calculator" function. The field key to be used is specified here. It can be a constant string or can include variables as explained below under variables. If not specified, the default field key in each measurement is the string 'value'.

measurements

measurements

The set of *measurement*s that will be sent at each interval. The editor uses the "calculator" interface to create scripts to generate data using the various eMon Energy inputs. Each entry will generate a measurement using the influx line protocol:

<measurement>[,tag-key1=tag-value1[,tag-key2=tag-value2...]] field-key=field-value time

Note that measurement, tag-value, and field-key are specified above and can be fixed strings or can be or contain variables. Some examples of the various ways this can be used to create different types of measurement specifications are given below.

As each measurement is written the $name and $units variables are assigned the value specified in the individual measurement specification.

The units of the field set defaults to watts. While Watts is the typical unit reported, the following additional units are available.

  • watts

  • volts

  • VA

  • pf

  • Hz

  • kW

  • wH

  • kWh

Once configured, a new influx service will be created. The current state of the service and the date/time of last update will be displayed under the influxDB tab in the status display.

influx status bar

The service can be started and stopped using the start/stop button. When a running influx service is changed, the service is automatically stopped and restarted.

Variables

Variables provide a way to further customize the way data is organized in your influxDB database. This tutorial will not get into the implications of different conventions, except to say that future generic visualization templates may be based on using the default specifications for measurement and field key.

There are three variables defined:

  • $device - The name assigned to this eMon Energy device in the device configuration section.

  • $name - The name specified for the current measurement

  • $units - The units specified for the current measurement

When these variables appear as all or part of the string specified for measurement field key or a tag value, the instance of the variable name is replaced by it's value. Evaluation proceeds left to right in a string.

So as an example, when generating a measurement configured as:

**Influx Solar Output**

with a device name of eMonHome and the current value of the input solar of 2944.6, the following different measurements could be generated:

measurement

tag-value

field-key

measurement sent to influxDB

$name

value

solar value=2944.6 1523810195 (This is the default)

$units

$device

$name

kWh,tag1=eMonHome solar=2944.6 1523810195

$device

$name

$units

eMon,tag1=solar kWh=2944.6 1523810195

$name.$units

value

solar.kWh value=2944.6 1523810195

power

&device.01

$name

power,tag1=eMon.01 solar=2944.6 1523810195