Mitsubishi Electronics QD75P Allowable circular interpolation error width, Example Near pass

12 CONTROL SUB FUNCTIONS

MELSEC-Q

(3)When continuous path control of a circular interpolation is being carried out in the near pass, an address in which the extra movement amount is subtracted from the positioning address of the positioning data currently being executed is replaced by the starting point address of the next positioning data No. Because the starting point address will be replaced, an error "Large arc error deviation" (error code: 506) may occur.

In this case, adjust the "

Pr.41

Allowable circular interpolation error width".

Positioning data No.2 starting point address during the near pass

Positioning data No.1

Address designated by positioning data No.1

	Positioning data No.2
	Path of positioning
Path of near pass	address pass

Fig. 12.12 Arc error during the near pass

(4)When a circle center is designated to continuously designate the circular interpolation control by a continuous path designation in the near pass, and the positioning address and starting point address of that arc are the same address, the path will make one circle using the two data items. This is because the 2nd data starting point address is shifted by the extra amount of

the movement amount occurring from the 1st data.

Example

[Near pass]

Starting point address of positioning data No.1	Path of positioning data No.2
	Starting point address of
	positioning data No.2

Path of positioning data No.1

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