Sample Exam Solutions for Review

[rdeka]

Is there an issue with using Projects and LabVIEW templates for CLD? Are they not supposed to be used in CLD exams?

In my opinion, QMH and DQMH templates provide a pretty good starting point for a UI based application.

[wiebe@CARYA]

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@rdeka wrote:

Is there an issue with using Projects and LabVIEW templates for CLD? Are they not supposed to be used in CLD exams?

In my opinion, QMH and DQMH templates provide a pretty good starting point for a UI based application.

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You can use everything that is in a default LabVIEW installation.

So (AFAIK, never used either) QMH: yes, DQMH: no.

[rdeka]

Thanks for the tip. DQMH usually comes with additional JKI Install. Unless I plan to create a DQMH from ground up, I will stick with QMH for CLD.

Please let me know if you find any issues with my solutions. Any feedback (like previous ones) would be appreciated.

Cheers,

Rahul

[CMSys]

Could you please give me a straight forward criticism of my Boiler application?

Much appreciated 😁

[rdeka]

Hi @CMSys,

I could not open the VIs as I am running on LV2023Q3.

Is it possible for you to drop a package with LV2023Q3 version or older?

Cheers,

Rahul

[CMSys]

Yes, here it is. 

[rdeka]

Hi CMSys,

Please see my feedback below:

High Level Feedback:

1. Folder/File Structure: Try to keep or follow a similar folder structure for saving of VIs as given in the exercise. For example, for place the used subVIs in SubVI folder. I did notice that you didn't need to do that because you did not have any subVIs (more on that later)

2. Broken VI: The VI was broken. I don't know if it was because of saving it to an older version, but the VI had a broken wire on the VI reference.

I believe it is more preferable to submit a semi-functional application than an almost completed but is broken and not able to execute. So make sure that your VI runs without error before the time is up 

3. Architecture: Seems like you have selected Producer Consumer Architecture with a Queued State Machine. Since there is no template for Producer Consumer Architecture with a Queued State Machine, you had to spend time to create a template first, before working on it. Another issue you are going to have is sync issue with the Producer Consumer Architecture you created is SYNC. Instead of using Wait(ms) function, use Wait until next ms Multiple function, which will sync both the loops and minimum input from the producer loop will be missed by Producer loop.

Also, to avoid creating a template for  Producer Consumer Architecture with a Queued State Machine, may I suggest you sure Queued State Machine like in the example solution or Queued Message Handler Architecture. There are templates in LabVIEW you are allowed to use during CLD exam

Furthermore, in your Consumer loop, do not have Initialize case and Default be the same case. This will lead to unexpected Initialization when certain cases are not found. Try displaying some sort of error message in Default case. 

4. SubVIs: Whenever, you have to do an operation more than once, create a SubVI for it. Especially in this case, you should create a subVI for Data logging.

5. Documentation: VI and Type Defs are missing documentation and still have default icon

Feedback on the Code:

6. Button Latching: Update the Mechanical Action of the button to Latch When Released, otherwise, the buttons do not go back to its OFF State, ready to be pressed again

7.Minimise use of Property Nodes: Minimise use of Property node of SubVI if you can. For example, in the following screenshot, you did not need to have the references and the Property Node, you could get the state of Run Interlock Switch directly from the Controls. See the subsequent screenshot.

8.Non-Sequential Operation: According to the exercise instruction, there is specific Sequence of operation that is suppose to be followed. This means certain buttons needs to be either Disabled and Grayed out or does not impact the test going forward once their operation is completed. In your case, I can go from Boiler Reset to Pilot On and then Start Sequence.

9. Pilot Indicator Blinking Inconsistent: The Pilot Indicator is not controlled and is on and blinking during sequences it should not have.

Suggestion: 

Use Templates: As mentioned before use existing Templates in LabVIEW. Start using them in Success Package exercises before using them in sample papers to get the hang of it.

Training: 

• If you have time and have access to it, do LabVIEW Core 1 and 2
• Do success package and sample papers over and over
• Watch CLD Exam Preparation Video. This gives the key outline on what the assessors are looking for (https://learn.ni.com/pages/certified-labview-developer)

• Use VI Analyzer. Assessors use them as well and they give you an idea on what you can do differently next time.

• Keep asking questions.
• Practice. Practice. Practice.

I have attached one of my Boiler Solution for reference. Hope this helps.

Kind Regards,

Rahul Deka

[CMSys]

First off, thank you for giving such descriptive and detailed feedback. 

1. I believe I kept to the original file structure, did I misplace a control? 

2. Why would that have broken? It wasn't broken when I compressed the file. What should I do to prevent this? 

3. Agreed, I will use the QMH next time, I'm fairly familiar with it. 

4. I should have done that by probably having an argument for my regular expression, string, and number correct? 

5. Darn I thought I covered my bases. 

6. Which buttons? I didn't think I was allowed to alter the front panel or its controls/indicators

7. Agreed, is there an easier way to blink the indicator, or should I just create some code that will do it? 

8. Agreed

9. That one got me, I wasn't able to use a property node (a fancy local variable) to turn it off, why is that? 

Overall, would it have passed? 

Respectfully, 

CMSys

[rdeka]

Hi CMSys,

1. I don't think you did, but the folder was missing SUbVI folder, but like I said, you technically didn't need to use it because you did not have a subVI

2. If it was not broke when you compressed it, do not worry about it since you do not need to compress it during exam. It could be Windows being Windows

4. There is multiple ways to skin that cat, but I believe the Event Logging can be made a SubVI and easily used wherever required

6. All the buttons in Boiler Control Cluster. I believe the requirement is NOT to Rename them and change file hierarchy. If unsure, feel free to reach out to NI certification team for clarification on that. Please let me know if I have got that wrong.

7. Actually using Property node to change the property of an object (eg, blinking) is correct use of Property Node. I should've said "Property Node Value". They are the ones that are considered fancy local variables. Just make sure you read the Sequence of operation and make the objects behave how you want and when you want.

8. You should've been able to. That is what I did. Check my example for reference.

I cannot make the assessment. I have not completed my CLD exam yet. Attempted twice but could not start due to technical issue on NI's end. Attempting again in 1.5 weeks.

But I would suggest to do more of success package exercise and keep re-doing sample papers. I keep coming up with new and efficient ways to do them each time I do it.

Kind Regards,

Rahul Deka

[CMSys]

This program is similar in structure. The next I create will be a QMH. What do we think of this one? My documentation will be much improved come exam time. I am mostly working on making things functional right now.