Hitachi SJ700-2 instruction manual Electronic gear function, P019 = 00 FB, P019 = 01 REF

Chapter 4 Explanation of Functions

4.3.7 Electronic gear function

The electronic gear function allows you to set a gain on the position command or position feedback data to adjust the ratio between the main motor and sub-motor speeds during the synchronous operation of the motors.

Related code

P019: Electronic gear set position selection

P020: Electronic gear ratio numerator setting

P021: Electronic gear ratio denominator setting

P022: Feed-forward gain setting

P023: Position loop gain setting

Item	Function code	Data or range of data	Description
Electronic gear set position	P019	00	Position feedback (FB) side
selection		01	Position command (REF) side
Electronic gear ratio numerator	P020	1 to 9999
setting (Note 4)
Electronic gear ratio	P021	1 to 9999
denominator setting (Note 4)
Feed-forward gain setting	P022	0.00 to 655.3
(Note 2)
Position loop gain setting (Note	P023	0.00 to 99.99 or 100.0 (rad/s)
3)

Note 1: Block diagrams for the electronic gear function are shown below.

			First order lag filter							Feed-forward gain
						1
										P022
					1+ST
									Position loop
		Position								gain	Speed
P019 = 00 (FB)										P023
		command									command
								Electronic
							Ｎ
								gear
							Ｄ
			Position-control feedback
			First order lag filter							Feed-forward gain
		Electronic		1
										P022
		gear				1+ST
P019 = 01 (REF)									Position loop
	Position									gain	Speed
			Ｎ							P023
	command										command
			Ｄ
			Position-control feedback

Note 2: You are recommended to set the feed-forward gain setting (P022) to 2.00 first when adjusting the feed-forward gain. To reduce the position deviation between the main motor and sub-motor, increase the feed-forward gain. If the motor operation is unstable, reduce the feed-forward gain.

Note 3: You are recommended to set the position loop gain (P023) to 2.00 first when adjusting the loop gain. To increase the positioning accuracy and position-holding force, increase the loop gain. If a high loop gain results in unstable motor operation, reduce the loop gain.

Note 4: The electronic gear ratio (N/D) must be within the following range: 1/50 ≤ N/D ≤ 20

N:Electronic gear ratio numerator (P020)

D:Electronic gear ratio denominator (P021)

4 - 101