Mitsubishi QD60P8-G, User Manual

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MELSEC-Q
3 SPECIFICATIONS
Buffer memory address
Item Details
Initial
value CH1 CH2 CH3 CH4 CH5 CH6 CH7 CH8
Pre-scale setting
value
• Set the pre-scale setting value.
• The pre-scale function calculates the "sampling pulse number" of
the buffer memory with the following operation formula:
Sampling pulse number =
input pulse value per count cycle pre-scale setting value
unit magnification
Note that if the pre-scale setting value is "0", the displayed
sampling pulse number becomes 0 from the above operation
formula, and therefore, it seems as if pulses are not counted
although they are actually counted.
• If the setting value is outside the range, a pre-scale setting range
outside error (error code: 400) occurs. To clear the error, turn ON
the error reset request (Y8 to YF) of the corresponding channel.
After this, set a correct value and then turn ON the operating
condition setting request flag (Y1).
[Setting range: 0 to 32767]
0 7 39 71 103 135 167 199 231
Accumulating
count value
• Stores the accumulating value of the "sampling pulse number" of
the buffer memory.
• The accumulating count value can be used when either the
linear counter or ring counter is selected.
• The accumulating count range is 0 to 99999999 for both the
linear counter and ring counter.
• If the accumulating count value exceeds 99999999 when the
accumulating counter is used as the linear counter, the "overflow
detection flag" of the buffer memory turns ON.
• When the operating condition setting request flag (Y1) is turned
ON or "1" is set in the "counter reset request" of the buffer
memory, the accumulating count value is reset.
• The update timing is the same as the cycle of the sampling pulse
number. (It is the interval set in the "count cycle setting value" of
the buffer memory.")
0
8
9 40
41 72
73 104
105 136
137 168
169 200
201 232
233
Input pulse value
• Stores the actually entered pulse number.
• This value is not converted into the unit pulse number by the pre-
scale function, unlike the "sampling pulse number" and
"accumulating count value" of the buffer memory.
• The count indication range is 0 to 2147483647.
• When the operating condition setting request flag (Y1) is turned
ON or "1" is set in the "counter reset request" of the buffer
memory, the input pulse value is reset.
• If an overflow error (error code: 100) occurs, this value is kept
counted when the count enable (Y18 to Y1F) is ON.
• The update timing is fixed at 10ms. Therefore, take care when
using the module as a counter.
0
10
11 42
43 74
75 106
107 138
139 170
171 202
203 234
235
Overflow
detection flag
• If the "accumulating count value" of the buffer memory exceeds
99999999 when the accumulating counter is used as the linear
counter, the overflow detection flag turns ON. At the same time,
an overflow error (error code: 100) occurs and count operation is
stopped.
• When the overflow error has occurred, the accumulating count
value does not change from 99999999 if pulses are input after
the error occurrence. The "sampling pulse number" of the buffer
memory is reset.
• The overflow error is cleared by setting "1" in the "counter reset
request" of the buffer memory. Count operation is resumed after
the error is cleared.
• The error is also cleared by turning ON the error reset request
(Y8 to YF). To resume count operation, however, turn ON the
operating condition setting request flag (Y1) or set "1" in the
counter reset request.
[Detection value]
0: No overflow detection (OFF)
1: Overflow detection (ON)
0 12 44 76 108 140 172 204 236
*: Refer to Section 9.3 for details of the error codes.