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MELSEC-Q
12 CONTROL SUB FUNCTIONS
(4) When the speed is changed by setting " Cd.14 New speed value" to "0",
the operation is carried out as follows.
A deceleration stop is carried out, and the s peed change 0 flag
(Md.31 Status: b10) turns ON.
(During interpolation control, the speed chan ge 0 flag on the reference axis
side turns ON.)
The axis stops, but " Md.26 Axis operation status" does not change, and
the BUSY signal remains ON. (If a stop signal is input, the BUSY signal
will turn OFF, and " Md.26 Axis oper ation status" will change to
"stopped".)
In this case, setting the " Cd.14 New speed value" to a value besides "0"
will turn OFF the speed change 0 flag ( Md.31 Status: b10), and enable
continued operation.
Md. 31 status: b10
Positioning start signal
BUSY signal
Cd. 14 New speed value
Cd. 15 Speed change request
Positioning operation
1000
0
ON
OFF ON
OFF
ON
OFF ON
OFF
Speed change 0 flag
[Y10, Y11, Y12, Y13]
[XC,XD,XE,XF]
Fig. 12.25 Speed change at new speed value "0"
(5) A warning "Deceleration/stop speed change (warn ing code: 500)" occurs
and the speed cannot be changed in the foll owing cases.
During deceleration by a stop command
During automatic deceleration during posit ioning control
(6) A warning "Speed limit value over (warning code: 501)" occurs and the
speed is controlled at the " Pr.8 Speed limit value" when the value set in
"Cd.14 New speed value" is equal to or larger than the " Pr.8 Speed limit
value".
(7) When the speed is changed during interpolat ion control, the required speed
is set in the reference axis.
(8) When carrying out consecutive speed changes, b e sure there is an interval
between the speed changes of 100ms or more.
(If the interval between speed changes is short, the QD7 5 will no t be abl e to
track, and it may become impossible to carry o ut commands correctly.)
(9) When a speed change is requested simultan eously for multiple axes,
change the speed in the ascending axis num ber order.
(10) Speed change cannot be c arried out during the machine OPR. A reques t
for speed change is ignored.
(11) When deceleration is st arted by the speed change function, the deceler ation
start flag does not turn ON.