Hello.

Faced a problem. For some unknown reason, during operation, the calibration of the upper camera and head 1 became incorrect. I noticed this after assembling several panels that all elements are located with a slight downward shift. The deviation was 0.2 mm along the Y-axis. I had to change the calibration "Mark Camera To Nozzle 1" from 36.7 to 36.9 mm along the Y-axis. Before this incident, I collected several dozen panels. Machine VP-2800HP.
Can you tell me why this could happen? How to deal with this?

In addition, we had to adjust the coordinates of the lower cameras, also by 0.2 mm. Since the microcircuits in the LQFP-64 cases were installed with an offset. For small components 0603, etc. it was not noticeable.
But now there is a problem. If two heads are used, then aligning the component with head 1 on camera 1 generates an error message. If one head is used, alignment and placement of the component occurs normally.
Tell me what to do?
Camera coordinates limit.png - Bild entfernt (keine Rechte)

Found a problem, error messages "Coordinates limit reached, end". The documentation helped. There was an air leak at the joint. Shown in the picture.
With the calibrations of the nozzle relative to chamber 1, everything was also in order.
Air Leak.png - Bild entfernt (keine Rechte)
Error.png - Bild entfernt (keine Rechte)

There was a leak from the very beginning of use. Couldn't find her. I thought it was necessary.

The problem has been resolved.
An air leak was in the transparent hose mount, indicated by an arrow.