A Return to Advanced Graphs in the EM4x energy manager


An Advanced Graphs page was introduced in the EM4x energy manager controller (in the Food Fight release, version 7.0), with four customisable graphs displaying on a single page for ease of visualization of a DC system in action.

The natural question is then just what should be done with the graphs? Enatel has as default a selection of standard DC system parameters in the primary graph that displays on the Overview page. Battery Current, Battery State of Charge, Rectifier Voltage, Rectifier Current, Renewable Current, Ambient Temperature, Load Current are all fundamental to a typical hybrid system.
So what else could be considered?

DC System Parameters

To a degree this is system specific, in that you are limited by what you are monitoring from the equipment. Still let us look at some common examples.

A mainstream use case of custom graphing is temperature profiles. Where a user is monitoring ambient temperature versus the battery temperature – to take in at a glance how the two interact. With the inbuilt temperature sensors it is a simple matter to map these to an advanced graph. Click on the Gear icon to bring up the variable option selection. Select Inputs from the field dropdown menu and then select the required temperature.

Similarly, a user can graph battery voltages, either string voltages or bloc voltages in a string to monitor the battery balances while effectively seeing the state of health of the batteries.

Graphing Individual Loads

For systems with multiple loads of different priority, with shunts measuring a primary and secondary load, it is an easy matter to graph the power draw of each load. Here we establish custom variables for each load derived from a basic input configuration calculation. The custom variable presenting in the graph dropdown menu a couple of clicks away.

Phase Balancing

Popular with Enatel’s phase balancing feature is to observe this in action over time. So that as loads draw power from each phase the user can watch the phases being balanced as it happens graphically, confirming correct functionality and providing a visual image of where the loads are sitting with regards a phase back off limit. We have the standard real-time bar graph on the Overview page as follows showing the back off limit at 20A.

This compared with a historical line graph set up on the Advanced Graphs page. Pictured below is a single IO Board managing two AC Monitors each measuring three input currents.

Modbus Derived Parameters

As the Modbus Master feature gains increased adoption we have multiple occasions to graph the information obtained via Modbus. Key here is the third party batteries that have a Modbus RTU enabled BMS. As the batteries cycle critical information can be presented in an intuitive graphical manner.

Expert Use

For the expert user we can provide information defined in the Lua editor. An example is the current and voltage of our solar modules as they operate with solar panels in different conditions. This can be helpful to understand if panels are dirty, shaded or have some other fault.

Note that all the information graphed can also be included in the periodic logs so that the user may look back and see exactly when specific issues observed initiated or how the situation compares in a different season.

So there we are, a few ways to make use of Advanced Graphs. Should you have an item requiring graphing that you are unclear about how to implement please contact us here.