INTRODUCTION
We get this question from time to time so I decided to write an article explaining what happens. When collecting data from automatic machines there are a couple options on how to deal with changes to the parts coming from the machine. These two drop down lists can be found under Tools > Options > Data Collection > Actions in QC-CALC Real-Time 3.0 and higher. Please keep in mind that the following works for most machines. Some machines, however, allow duplicate feature labels, etc and we have to treat them differently. Please consult with Prolink about your particular machine if you are getting unexpected results.

QUESTION
What is the difference between "Always Adapt" and "Rename existing QCC file, and create new file. (Recommended)"?

ANSWER
The answer has a lot to do with how to deal with a QCC file when the number of features doesn't match the number of features that were just inspected. In other words, you have 10 features in the file, but 12 just showed up because you decided to measure two extra on the last part. There are several options, but we're going to discuss two of the major ones here; "Always Adapt" and "Rename existing QCC file, and create new file. (Recommended)".

When combined with Update Nominals there are different options so I'll list each and the pros and cons.

"Always Adapt"

Always Adapt looks at the feature labels when you are collecting data. Therefore, if you change the order of the features, it doesn't matter since it matches up the names and simply moves the features within QC-CALC to match the file. This obviously requires unique feature labels or QC-CALC will become confused and not know where to place the features when it finds more than one feature called i.e. "x position". In addition, if new features are added (regardless of their position), they are automatically inserted where they need to be. This is convenient because you can insert 2 features in the middle somewhere and it adapts quite nicely. The downside to this is when you attempt to change the names. Since Always Adapt is depending on the names to stay the same, it will create a new feature for names it hasn't seen before and place deleted points where there is no value. Therefore, if you change a feature name from "Jason" to "Jason2" on the next inspection, it will place a deleted point in "Jason" since no value arrived by that name, and create a new feature called "Jason2" with the point in it. All points before that point in Jason2 will be set to deleted since (as far as it is concerned) Jason2 didn't exist before.

Always Adapt + Update Nominals = Always
When Update Nominals is set to Always, it will automatically update nominal and tolerance values coming from the machine. Feature label changes are not taken into account for obvious reasons above.

Always Adapt + Update Nominals = Never
When Update Nominals is set to Never, all nominals and tolerances stay the same regardless of what comes from the machine.

"Rename Existing File..."

Rename Existing File.. looks at the ordinal position of the feature in order to determine how to deal with the data in the file. Since the position is used, you can change the labels and they will reflect as long as Update Nominals is set correctly (see below). This is convenient if you need to change the labels. Keep in mind that it will only actually rename the existing file and create a new one (as it says in the option description) if the actual number of features changes (i.e. from 4 dims to 6 dims). If you are simply renaming features, it keeps the same file. The downside to looking at the ordinal position is that it doesn't pay attention if you re-order the features. As such, it will place the data in the wrong place. For example, if you swap features 4 and 6 and the number of features didn't change, the data will suddenly not look right in QC-CALC. If you swap features and add two new ones, you're fine since it will create a new file anyway. Likewise, if you insert a feature between 5 and 6, this would be ok since it would cause the counts to mismatch which would generate a new QCC file with the correct features.

Rename Existing + Update Nominals = Always
When Update Nominals is set to Always, it will automatically update labels, nominals, and tolerances coming from the machine.

Rename Existing + Update Nominals = Never
When Update Nominals is set to Never, all labels, nominals, and tolerances stay the same regardless of what comes from the machine.