Logical Devices
Logical devices are virtual devices available in powermanager. They can be used to setup certain calculations, formulas and derive measurement values from physical devices. These devices are used to calculate average, convert energy to power, power to energy, calculate key performance indicators (KPIs) and energy consumption.
The following types of logical devices are available in powermanager:
The average value device is a logical device, which enables the user to calculate the average value of measurement point from a physical device or another logical device over a specific time period. You can configure an average value device to calculate values over hours, minutes, or seconds.
To use a device not listed under Powermanager Devices, as a source the device, drag and drop the device to the Source expander.
After configuring an average value device, the user can monitor, represent, and archive the average value calculated by the device.
If a device not listed under Powermanager Devices, is configured as the source device for Average Value, is deleted, it is highlighted with red under the Source expander.
Calculations with an average value device are delayed by fifteen seconds.
A calculation value device is a virtual device, which allows the user to create and evaluate arithmetic or Boolean expression in which the variables represent values of data points from devices. These arithmetic and Boolean expressions are evaluated when one of the data point (variable) value present in the expression changes, and the result is updated into the virtual device.
To use a device not listed under Powermanager Devices, as a source the device, drag and drop the device to the Source expander. A measurement point used in a calculation value device cannot be added as a source measurement point to the same device, but can be added as source measurement point to other calculation value devices.
If a device not listed under Powermanager Devices, is configured as the source device for Calculation Value, is deleted, it is highlighted with red under the Source expander.
Calculations with a calculation value device are delayed by fifteen seconds.
A converter is a logical device which helps the user to convert the power values to corresponding energy values over a given interval of time or vice versa. Once a converter device is configured, the user can monitor and archive either the power or energy values calculated.
During conversion the unit of the converted values will be derived as follows.
- kWh unit is derived from kW unit or vice versa
- varh unit is derived from var unit or vice versa
- kVAh unit is derived from kVA unit or vice versa
Calculations with a converter are delayed by fifteen seconds.
A Key Performance Indicator is a measurable value that demonstrates how effectively a company is utilizing energy. Using this device you can generate the Key Performance Indicators (KPI) of any building or industry. A KPI (Key Performance Indicator) device allows the user to custom-define KPIs. The user can define how the KPI is calculated. KPIs can be calculated according to time ranges like hour, day, week, month, and year. To use a device not listed under Powermanager Devices, as a source the device, drag and drop the device to the Source expander.
For every new KPI that is added, the user can use all elements for the calculation. There is the possibility to either calculate with measurement point elements, static values and variable that can be edited globally, for example, numbers of employees, square meters, etc.
If a device not listed under Powermanager Devices, is configured as the source device for KPI, is deleted, it is highlighted with red under the Source expander.
Calculations with an KPI device are delayed by fifteen seconds.
The Virtual Counter is used to calculate the consumption values such as active energy, reactive energy and universal counter from a physical device or another virtual counter device.
For example, consider a scenario wherein a system consists of an incomer connected to two outgoing feeders and the energy meters are only available at the incomer one of the outgoing feeders. You can calculate the energy values of the outgoing feeder without the energy meter, by configuring the virtual counter accordingly.
Calculations with a virtual counter device are delayed by fifteen seconds.
