Understanding user permissions and Niagara Ax NAV file relationships.

 NAV file relationships.

The category service is used to assign logical groupings to station resources, such as HVAC or lighting zones, user management, histories, etc.

Users should be assigned permissions to access the categories based on what type of user they are on what functions that they need access to.

•  Permissions are broken down into two groups, operator and admin.

•  Each group has three permissions which can be assigned. R = read, W = write, I = invoke. Operator permissions are indicated by lower case letters and admin permissions are indicated by upper case letters.

•  Individuals with only operator permissions can still be given authority to command a point which normally requires admin permissions by modifying the config flags of the action on the points slot sheet to include the 'operator' flag.

•  Checking the 'super user' option is a convenience for checking all permissions in all categories, but also provides access to the local file system through Workbench. Users with

'super user' status will see all of the available drives instead of just 'sysHome' when navigating

My File System in the nav sidebar.

A user who has permission to manage users will only see other users listed in the user manager view for categories which they have permissions.

The nav file is used to provide a customizable link structure for graphics viewing without having to utilize framesets and custom navigation trees. Each user can be assigned one nav file to their user account. The nav file is not meant to be a security mechanism, although it can be used to limit the available navigation options when using basic profiles. It is important to understand that it does not prevent an operator from manually typing the correct ord in the URL field of the browser to access

a resource which they are not intended to have access to. Do not use nav files to restrict a user's access to station resources, properly configure the categories and user permissions to do so.

Downgrading a Niagara Ax JACE to a previous version

How to view platform info with a browser and not login to the Niagara Ax station.

You have to know the platform user and password.

http://<ipAddress>:3011/platformInfo - this view provides much of the same information that is available through Workbench when looking at the Platform Administration view.

http://<ipAddress>:3011/qnx - this view is only available for JACEs which use the QNX operating system. This view provides much of the same information that is available through Workbench when looking at the spy pages.

How can you tell if Niagara Ax JACE is overloaded?

When using Workbench, right-click on the connected station in the nav sidebar and select View -> Resource Manager.

• The CPU usage should be less than 80% on a continuous basis.
• The heap.used should be less than 75% of the heap.max value. Execute garbage collection before evaluating the heap.max value by right-clicking on the connected station in the nav sidebar and selecting Spy -> util -> gc.

• For a SoftJACE ensure that the resource.total is less than the licensed resource limit. SoftJACEs are licensed for either a 10,000 KRU or 30,000 KRU limit. If actual station resources exceed 110% of the licensed limit for a SoftJACE, the station will fail to start.

If running AX 3.1 or later, when using Workbench right-click on the connected station in the nav sidebar and select 'Spy'. On the Remote Spy page select 'platform diagnostics' and then 'fd usage'. This displays a list of processes and the number of open file descriptors for each.

QNX-based JACE controllers are limited to 1000 open file descriptors. File descriptors include but are not limited to directories, files, histories, and socket connections. If the number of open file descriptors exceeds the limit, the station will behave erratically such as misreporting available file space, missing history collections, etc. A maximum of 800 histories per station is recommended to avoid exhausting the pool of available file descriptors.

What can the second Ethernet port on the Niagara Ax JACE-2 and JACE-6 be used for?

Currently the only drivers that can be configured to use the second Ethernet port are Bacnet, ModbusTCP and EibIp.

The JACE does not act as an Ethernet router or switch, meaning it does not allow TCP/IP traffic to pass from one port to the other.

The second Ethernet port can be used to isolate a BACnet Ethernet or IP network from the primary LAN. All BACnet devices would be connected on the network segment that was connected to the secondary Ethernet port on the JACE. BACnet points that are proxied in the station could then

be viewed or commanded through graphics that are served up by the webService via the primary

Ethernet port.

The Niagara Network and the webService will be available on both network interfaces. With BACnet, you select which network interface to use on the link settings of the IP-port and/or Ethernet-port object under the BACnet network. With Modbus TCP the IP layer decides which network interface to use based on the IP address assigned to the Modbus TCP Device Object.

The second port must be on a different subnet. The second subnet cannot also have a default gateway - so you will be limited to one subnet on the second network interface.

How to set the BACnet server to TRACE in Niagara Ax

Right-click on the station in the nav tree and select "Spy".

 Then click "logSetup" to go to the screen for configuring logs.

Here you can set each of the various logs in your station to different levels of output - from None (no output), Error (only ERROR messages), etc. up to Trace (which prints diagnostic-level output useful for identifying problems when troubleshooting ).  The default level for all logs is Message.  Click the cell in the Trace column, and the row labeled "bacnet.server".

Then the station output will display trace-level messages for the bacnet.server log.  From this you should be able to see where the requests are coming from and configure the offending device properly.  In order to avoid unnecessarily burdening the station, you should turn trace debug off (by setting back to Message) when you are finished.

Note that log settings DO NOT persist across station restart, unless you click the Save To File link at the top.  This will save them to the /lib/log.properties file, which is read upon station startup to initialize the log levels.

An Introduction to Color Theory for Web UI Design

What is Color Theory?

Color Theory actually covers a number of things, but at the most basic level it is the interaction of colors in a design through complementation, contrast, and vibrancy.While the first part of this definition is straightforward (and admittedly bland), it is the last 3 terms which define the basic Color Theory:

Complementation

Complementation refers to the way we see colors in terms of their relationships with other colors. When colors occupy opposite ends of the color spectrum, they lead people to consider a design visually appealing by establishing a happy medium the eye can reside in. Rather than straining to accommodate for a particular area of the color spectrum, the eye is provided a balance. Complementation can take you to new heights of design sophistication when you can begin to master the intricacies of color combinations.

Contrast

Contrast reduces eyestrain and focuses user attention by clearly dividing elements on a page. The most apparent example of contrast is an effective selection of background and text color, as shown below:

If you’re ever in doubt, the best practice is usually to choose a very light color for the background, and a very dark color for the text itself. This is one area where color theory is crucial to the usability of a Web UI Design; In most projects, large text areas aren’t a place to try to be really creative – so keep it simple and legible.

Along with establishing readable text, contrast can also draw the viewer’s attention towards specific elements of a page. Think about highlighting a textbook: when you want to draw your attention to a specific portion of the page, you make the surrounding area look different than the rest of the text. The same principle applies to Web UI Design: Using a variety of contrasting colors can help focus the viewer’s attention on specific page elements.

Vibrancy

Not to sound silly, but vibrancy dictates the emotion of your design. Brighter colors lead the user to feel more energetic as a result of your design, which is particularly effective when you are trying to advertise a product or invoke an emotional response. Darker shades relax the user, allowing their mind to focus on other things.

Ways to Make Your Life Easier

Thankfully, there are a few tools at our disposal that make color selection extremely easy when utilized properly. And best of all, they will further our understanding of Color Theory.

By experimenting in a guided environment, we are able to learn how to apply these principles without becoming frustrated when things are not working perfectly. Think of these tools as a sort of “color theory safety net”, to help you explore your own creativity without ever needing to stray far from the established rules for pleasing color combinations.

Kuler

A tool developed by Adobe, Kuler is aimed at providing an intuitive way to create a color palette. Every color on the palette can be individually modified, or chosen as the base color, with a few simple clicks. Palettes can be saved and published, and there are a number of great community entries available on their site. Under each color, the export codes are provided (including hexadecimal). However, the interface can be cumbersome at times, adjusting the vibrancy of a specific color can alter the entire palette (I wish they had a “lock” feature which prevented other colors from shifting). Overall, I would recommend this tool for those with a decent grasp of the concepts and patience for when things don’t run as smoothly as they would hope.