Mitsubishi Electric QD62, User Manual

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MELSEC-Q
6 CONVENIENT USAGE
6 CONVENIENT USAGE
6.1 Selecting the Counter Function
By selecting the counter function with the counter function selection setting, the disable
count function, latch counter function, sampling counter function and periodic pulse
counter function can be used.
The counter function selection can be executed by writing the data shown in the table
below into the counter function selection setting buffer memory (address 9
H
(29
H
)} and
by using the counter function selection start command (voltage applied to the function
start input terminal or turning Y06 (Y0E) ON using the sequence program).
Also, for the counter function selection, only one of the following four functions can be used.
Counter function selection Set value Remarks
Disable count function 0 Initial value (default)
Latch counter function 1
Sampling counter function 2
Periodic pulse counter function 3
(1) Disable count function
This function stops the count while the counter function selection start command
is being entered when the count enable command (Y04 (Y0C)) is ON.
(2) Latch counter function
This function latches the present value at the time the counter function selection
start command was entered to the latch count value (addresses C
H
to D
H
(2C
H
to 2D
H
).
(3) Sampling counter function
This function counts the input pulses during the preset sampling period since the
time the counter function selection start command was entered.
(4) Periodic pulse counter function
This function stores the present value and previous value for each preset periodic
time while the counter function selection start command is being entered.
POINT
(1) Change the counter function while the counter function selection start
command is OFF.
(2) The counter function selection can be executed either by turning Y06 (Y0E) ON
or applying voltage to the function start input terminal. Also, the signal that was
entered first takes precedence.
(3) Time settings for the sampling counter function and the periodic pulse counter
function are performed by writing data in a range from 1 to 65535 into the
sampling/periodic setting buffer memory {address A
H
(2A
H
)}. The time unit is 10 ms.
(Example) When 420 is specified in the sampling/periodic time setting buffer memory
Setting time = 420 10 = 4200 [ms]
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