You did Define Initial HMI Roles & Users in a previous step, now you are ready to use them inside the Data View to protect data variables from being manipulated by users that should not have access to them.

1. Open Data View and follow the Importing Data From Data Sources Into Your Project guide.

   Now that we’ve got some data available we can start limiting access to it.

1. Select the variable you want to limit access and then locate the Restrictions (Data Variable Property) Property Group on the right side of the screen.

   By default, all variables can be read by everyone, but writing to them is prohibited. You explicitly have to allow roles to manipulate a certain variable.

Default settings for all data variables in HELIO

1. In this example you allow only the members of the Service group to change the values of this variable.

1. Switch to the Content View, add some Magic Output (Element)s, link them to the restricted variable, and sign in (see Authenticate User) using different users. Only the users with Service roles should be able to actually write a value for this variable.

<aside> <img src="/icons/dance_gray.svg" alt="/icons/dance_gray.svg" width="40px" /> Good Job!

You’ve made your HMI more secure by protecting your machine’s data. Now it’s time toRestrict or Permit Access to Pages

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