Mitsubishi Electronics QD75P Controlling instructions, Condition 1. Number of output pulses

12CONTROL SUB FUNCTIONS

[4]Controlling instructions

MELSEC-Q

(1)When an absolute position detection system is constructed, absolute position restoration must be made at least once after power supply on or resetting. Also, the servo amplifier does not switch on unless the absolute position restoration is completed.

(2)For use of positioning in an absolute position detection system, the following controls cannot be carried out:

•Limitless-feed control which exercises control only in the fixed direction, e.g. turntable

•Control where the movement amount from the OP address exceeds the range of the following conditions 1 and 2

When performing positioning in an absolute position detection system, use it in the range which satisfies Conditions 1 and 2 given below.

In the range which does not satisfy Conditions 1 and 2, positioning cannot be used in the absolute position detection system since the normal current value cannot be provided during absolute position restoration.

Condition 1. Number of output pulses

a)Indicates the number of pulses that may be output to a servo amplifier when an axis is to be positioned from the OP in an absolute position detection system. In the absolute position detection system, pulses within the range of the following expression can be output to the servo amplifier.

[-32768 (number of feedback pulses)]≤ [number of output pulses]≤ [32768 (number of feedback pulses)-1]

b)Pulses are positive in the address increasing direction from the OP, and negative in the address decreasing direction from the OP.

		OP		Unit: ∝ m
-214748364.8		0	214748364.7
	Negative pulse outputs		Positive pulse outputs

c)The number of output pulses varies with the number of feedback pulses as indicated below:

•When the number of feedback pulses is 8192 (pulse): -268435456 (pulse) to 268435455 (pulse)

•When the number of feedback pulses is 16384 (pulse): -536870912 (pulse) to 536870911 (pulse)

Condition 2. Positioning address

a)The following positioning addresses can be specified on the QD75:

•When the unit is mm: -214748364.8 (∝ m) to 214748364.7 (∝ m)

•When the unit is inch: -21474.83648 (inch) to 21474.83647 (inch)

•When the unit is pulse: -2147483648 (pulse) to 2147483647 (pulse)

•When the unit is degree: 0° to 359.99999°

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