MS_IoTCentral_Temp_Stack_Light_PLC_Demo

MS_IoTCentral_Temp_Stack_Light_PLC_Demo

In this example, you begin by learning the basics of working with Electric Imp. We will use Electric Imp Libraries to seamlessly connect imp-enabled hardware to Azure IoT Central. Your imp-enabled hardware device will report environmental sensor data through the Electric Imp impCloud into Azure IoT Central. This example uses an impAccelerator Fielbus Gateway and the Electric Imp Modbus Library to monitor the temperature via a Click PLC. The temperature is monitored locally by a Stack Light that the Click PLC triggers when the temperature has reached a threshold value, and also remotely by sending data to Microsoft Azure cloud by using the Electic Imp AzureIoTHub libray. Once data is in the Azure cloud the temperature can be monitored using your Azure IoT Central application.

What You Do

• Configure your impAccelerator™ Fieldbus Gateway with BlinkUp™.
• Create an Azure IoT Central application.
• Register your device in IoT Central.
• Run a sample application using the impCentral to send sensor data to Azure IoT Central.

What You Learn

• How to configure your imp-enabled device with BlinkUp.
• How to use impCentral.
• How to create an Azure IoT Central application.
• How to register your device with Azure IoT Central and get your connection string.
• How to collect temperature data from a sensor.
• How to send sensor data to Azure IoT Central.

What You Need

1. Your 2.4GHz 802.11bgn WiFi network name (SSID) and password.
2. A computer with a web browser.
3. A smartphone with the Electric Imp app (iOS or Android).
4. A free Electric Imp Account.
5. A Microsoft Account.
6. impAccelerator™ Fieldbus Gateway
7. C0-02DD1-D Click PLC.
8. 10k NTC Thermistor.
9. 10k Resistor.
10. Stack Light.
11. 24V Power Supply.
12. Wire.

Hardware Setup

1. Connect Fieldbus Gateway to Click PLC via RS485.

2. Connect 10k Thermistor to Click PLC with 10k resistor.

• Thermistor (Black Wire) -> PLC ACOM
• Thermistor -> 10k Resistor
• 10k Resistor (Red Wire) -> Power Supply 24V
• 10k Resistor (Yellow Wire) -> PLC analog in AD1 I

3. Connect Stack Light to Click PLC.

• Green Wire -> PLC Y1
• Yellow Wire -> PLC Y2
• Red Wire -> PLC Y3
• Grey Wire -> Power Supply 0V

4. Connect the PLC to the power supply.

• PLC power (on the bottom of the unit) to the Power Supply terminals.
• Power Supply 24V -> PLC C2

5. Connect the Fieldbus Gateway to the power supply.

Assembled, the hardware should look like this:

Configure Fieldbus Gateway

To get started with a impAccelerator™ Fieldbus Gateway follow the steps below, or for more detailed instructions you can visit our DevCenter's Getting Started Guide.

Electric Imp BlinkUp

Open the Electric Imp mobile app on your smartphone to configure your device.

1. Log into your Electric Imp account.
2. Click on Configure a Device
3. Select Wireless
4. Enter your 2.4GHz 802.11bgn WiFi credentials, then click Next
5. Follow the instructions in the app to configure your device for local network access.
6. If you have any trouble here is a link to the DevCenter's BlinkUp instructions.

How Electric Imp’s IoT Connectivity Platform Works

The Electric Imp Platform has two main components: the imp-enabled device and the impCloud™. The imp-enabled device runs the device code, which in this use case consolidates the data gathered from the temperature sensor via the Click PLC. Each device is paired one-to-one with its own online assistant — or, as we call it, an ‘agent’ — in the impCloud and which runs the agent code. The device sends this data to its agent. In this example, the agent code relays the data to the Azure IoT Central cloud. Here’s a broad overview of this flow:

With impCentral Electric Imp provides all the tools you need to write and deploy the software (to the device and to its agent) that will control your imp-enabled connected product. impCental runs in a desktop web browser and communicates between the device and cloud solutions.

Working With impCentral

1. Open your web browser and log in to the impCentral.
2. Click the + Create New Product button to create a new Electric Imp application.
3. In the pop-up panel, name your Product and Development Device Group and click Create. A code editor will automatically open.
4. Next you will need to assign your device to the Device Group you just created. In the bottom section of the code editor click the Assign devices button.
5. In the pop-up panel find your device and click Assign.
6. If you have any trouble here is a link to the DevCenter's impCentral guided tour.
7. Copy and paste the application code from GitHub into the code editor.
   • Agent Code should be placed in the Agent Code window to the left in the code editor.
   • Device Code should be placed in the Device Code window to the right in the code editor.

Azure IoT Central Set Up

Create an IoT Central Application

1. Login to Microsoft IoT Central, click + New Application:

2. In the pop-up panel select:

• Choose payment plan: Free.

• Select an application template: Custom Application.

• Enter an Application Name: YOUR APPLICATION NAME. For this example I'll use the name: Connected PLC Demo. Note: The URL field will auto poplutate to match the Application name.

• Click Create button. You will be redirected to your Applicaation's home page.

Create an IoT Central Device Template

1. On the Homepage Click on the Create Device Templates shortcut to create a device template. This will also create your first device of this type:

2. Enter the name for your device template. For this example I'll use the name Fieldbus-PLC, since my devices will be Fieldbus Gateways with PLCs attached:

3. After creating a device template your first simulated device will be automatically created. You can edit the device name and upload a photo if desired.

4. Next we need to match the data that the imp is sending via the application code with the device template we are creating. For this application we are going to track temperature and temperatureAlert telemetry data. The data structure is defined on lines 183-186 of the example device code (see code snapshot below):

// Create data table to send to agent
local data = { "temperature"      : temp,
               "temperatureLimit" : tempThresh,
               "temperatureAlert" : alert };

5. Add temperature to the device template:

• Click + New Measurement

• Select Telemetry.

• Fill in Telemetry form:

• Fill in the Display Name, this will be displayed in your application.
• Fill in Field Name, this must match the code from your device, so for this example this field must be temperature.
• (Optional) fill in Units, for this example degC.
• (Optional) Minimum Value, graphing will use this value to set the y axis, so choose a value that makes sense for your application. I have used a value of 10.
• (Optional) Maximum Value, graphing will use this value to set the y axis, so choose a value that makes sense for your application. I have used a value of 40.
• (Optional) Decimal Places, enter the number of decimal places your data should display. I have used a value of 0.
• At the top of the form click Save.

6. Add temperatureAlert to the device template:

• Click + New Measurement
• Select Telemetry.
• Fill in Telemetry form:
  • Fill in the Display Name, this will be displayed in your application.
  • Fill in Field Name, this must match the code from your device, so for this example this field must be temperatureAlert.
  • (Optional) fill in Units, for this example I've left this blank.
  • (Optional) Minimum Value, graphing will use this value to set the y axis, so choose a value that makes sense for your application. I have used a value of 0.
  • (Optional) Maximum Value, graphing will use this value to set the y axis, so choose a value that makes sense for your application. I have used a value of 1.5.
  • (Optional) Decimal Places, enter the number of decimal places your data should display. I have used a value of 0.
  • At the top of the form click Save.

Connect your Imp to IoT Central

1. Navigate to the Device Explorer tab.

2. Click + New from the menu options, and select Real.

3. Click Connect the device from the top right just under the account info.

4. Copy the Primary connection string from the pop-up.

5. Open the impCentral code editor and paste the Primary connection string into the agent code DEVICE_CONNECTION_STRING constant on line 147 of the example agent code.

// Connection string from IoT Central
const DEVICE_CONNECTION_STRING = "<YOUR_DEVICE_CONNECTION_STRING_HERE>";

// Start the Application
IoTHubTempMonitor(DEVICE_CONNECTION_STRING);

6. Click Build and Force Restart to start running your application.

IoT Central will take about 10-15 seconds to start updating the telemetry data plot, at which point you will see the telemetry data coming from the Fieldbus Gateway.