My design is using an isolator between low voltage and main supply.

I'm using a design rule to set clearance beetween planes and tracks with this kind of query:

(InNetClass('HV') or InNet('GND'))           

Here's the result. As you can see, the isolator is itself too small to provide the spacing on pads between the two sides.

enter image description here

I would like to keep this isolation distance as a general rule but exclude this component from rules checking. I tried to change the query with the name of the component:

     (InNetClass('HV') or InNet('GND')) and (Name like 'U1_Isolator2*')     // the star character allows select the pads of the component

Here's the result:

enter image description here

It's better but I still have violations on tracks going to the isolator. I tried to check only on polygons with this expression:

(InNetClass('HV') or InNet('GND')) and IsPolygon

With this query, the "test queries" button returns a correct set of objects but if I click ok to close the design rule window, I get this message:

enter image description here

Based on these experiments, I have 2 questions:

  • Why is last query valid when I test it and not when closing the design rule window?
  • How can I achieve my goal?
  • \$\begingroup\$ One option is to simply IGNORE THE ERRORS. They won't stop you from making a PCB. You can have a board full of "errors", so long as you look at and understand each one. If you're doing 24 layer boards on a 6-person design team, maybe not a great idea. If it's just you, and you're doing a one-off board that you and only you are responsible for, that's a different story... \$\endgroup\$
    – Kyle B
    Dec 17, 2021 at 22:47

1 Answer 1


From Altium Documentation:


When defining an Electrical Clearance rule for polygon pours, you must use the InPolygon (or InPoly) attribute check, rather than the IsPolygon (or IsPoly) object type check. This is because the clearance rules operate on the primitives (regions, tracks and arcs) that make up, or are in the polygon pour, rather than the polygon pour as a whole object. A valid clearance rule for polygon pours would be between InPolygon objects and All other objects.


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