How to Trigger a Notification when an Sensor Value Exceeds a Threshold

Introduction

Any analog sensor can be used to augment machine data. For a machine that supports collecting data from the PLC, a second "Digital IO" data source will need to be added with a Labjack U3 connected directly to the MachineMetrics Edge via USB, or a T4 connected to an existing ethernet drop. 

Connect your Labjack

The first step is to connect your sensor to the Labjack. Follow the instructions in I/O Installation for more details around that. Verify that the data is being streamed properly viewing the value in the timeline. Here is an example configuration script that will serve as a tutorial for this article.

In this case, we will add a temperature sensor, and trigger a notification when the temperature exceeds 35 deg C.

device: labjack-u3
input:
  analog:
    temp_voltage:
      pin: 0
      sample-interval: 0.05
      min-delta: 0.1
data-items:
  sensor1:
    value: temp_voltage

This will output a raw data signal called "temperature" that is the voltage of the sensor. We will need to transform this to actual temperature, in this case, degrees Celcius. According to the sensor documentation, the conversion from Voltage to Degrees C = Voltage * 2.5 + 30. This can be included in the data-items transforms as shown below.

device: labjack-u3
input:
  analog:
    temp_voltage:
      pin: 0
      sample-interval: 0.05
      min-delta: 0.1
data-items:
  sensor1:
    value: temp_voltage * 2.5 + 30

 Check the Timeline of the machine, and verify that the data looks correct.

The next step is to add the condition that will indicate if the temperature has exceeded a threshold. This is treated essentially as an alarm condition on the machine. The alarm native code is required as notifications are triggered based on that - not the message. In this case, we set the code to mm01.

device: labjack-u3
input:
  analog:
    temp_voltage:
      pin: 0
      sample-interval: 0.05
      min-delta: 0.1
data-items:
  sensor1:
    value: temp_voltage * 2.5 + 30
conditions:
  temperature-high:
    message: High Temperature
    code: mm01
    value:
      FAULT: sensor1 > 35

Create the Workflow

In MachineMetrics, navigate to Workflows by clicking Automations in the sidebar menu.

On the Workflows page, select New Workflow to add a new Workflow. 

Fill in the fields with the required information. In this case, the most important field is the Trigger Event set to Alarm occurs. Then fill in the native alarm code, MM01.  I have given the Workflow a name that is descriptive of the value it is tracking, in this example, 'High Temperature.' 

Now, a Notification can be set for a designated User who will receive a Text and/or email notification whenever your temperature exceeds 35 degrees. Notifications are dependent on how the user's profile is configured.

If you have any questions, please contact support@machinemetrics.com