Creating virtual Math element

Owned by Technical Service Specialist
Last updated: Sept 05, 2024 by Vladimir Tayzhev
3 min read

Content

Introduction

The virtual "Math" sensor allows you to calculate the value according to the data of arbitrary sensors. For example, the diesel volume of an uneven tank can be calculated using a formula, some static data, and a level sensor data.

All Vutlan monitoring systems support adding a Math element.

Adding the Math virtual element

To create a "Math" element, press add button "" inside the "Group tree" or "System tree" menu. Then choose "Math sensor". A modal window will appear:

Click on the "Math sensor". Math element form will be opened:

Fields in the form available for change:

#

Name

Description

#

Name

Description

1

Name

Created element name

2

User-defined type

Defines the icon to be displayed in the "System tree"

3

Units of measurement

The unit of measure in which the value is displayed in the "System tree"

4

Minimum value

Determines the minimum measurement range, when the value is out of range, the sensor goes into the "Not connected" state

5

Maximum value

Determines the maximum measurement range, when the value is out of range, the sensor goes into a "Not connected" state

6

Alarm and warning levels

Defines the alarm and warning thresholds, as for other sensors, see Sensor configuration

7

Hysteresis

Option of setting the hysteresis state, see Sensor configuration

 

The configuration of data sources is available in the "Additional" tab:

Fields in the form available for change:

#

Name

Description

#

Name

Description

1

Expression

Function of the form f (x). To calculate the indirect value of the sensor is possible to use an arbitrary expression, which are permissible "(", ")", as well as:

  •  

    • operators: "+", "-", "*", "/", "%" (remainder of the division), "^" (exponentiation);

    • functions: "abs","sqrt","exp","ln","log","sin","cos","tan","asin","acos","atan";

    • constants: "pi" (3.1415926...), "e" (2.7182818...);

    • point is used as a decimal separator (3.14).

        For example: "0.1*x+0.5"

2

Polling period

Defines the update time of the sensor value

3

Add variable

Allows to add a new variable

4

Variable

Specifies a unique variable name A - Z, names cannot be repeated

5

Corresponding sensor

Determines the sensor whose value is used in the calculations

6

Delete the variable

You can use up to 26 variables with the names A - Z. Each variable can be associated with its own sensor, including the Math sensor.

Warning

If any of the sensors used as a variable source is not available, then the Math sensor will be in a "not connected" state.