INF-TN1FSH-E
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4.4.9.2. Setting total pulse (Total rate, pulse width)
Description
The measurement value (flow rate) can be integrated in response to the total pulse output from an integrating meter, etc.
as follows.
(1) Total rate:
When the total volume reaches the value specified by the total rate, the total pulse value on the
measurement screen is added, and 1 pulse is output for total pulse (volume).
(Setting range) 0 to 999999.999)
(2) Pulse width: The pulse width can be selected with the connected counters DO1/DO2 and DO3.
Set the pulse width when “F: TOTAL PULSE” or “R: TOTAL PULSE” is used in status output
setting.
•
Pulse width 1: Pulse width of DO3 (relay contact). Select one from the following.
50
msec, 100 msec, 200 msec
•
Pulse width 2: Pulse width of DO1/ DO2 (transistor open collector). Select one from the following.
0.5 msec, 1.0 msec, 2.0 msec, 5.0 msec, 10.0 msec, 20.0 msec, 50.0 msec, 100.0 msec,
200.0 msec
Note: If the total rate is set to “0,” the total pulse is not output.
Note: Set the total pulse in a state where the total mode is in total stop state.
Limitation in setting
The following limitations are imposed on the total pulse output.
DO output port
Frequency range of pulse output
(at full-scale flow rate)
Pulse width
DO1/DO2:
Transistor open collector
1000 pulses/sec or lower
0.5 msec, 1.0 msec, 2.0 msec, 5.0 msec,
10.0 msec, 20.0 msec, 50.0 msec, 100.0 msec,
200.0 msec
DO3: Relay contact
1 pulse/sec or lower
50msec, 100 msec, 200 msec
The maximum output frequency is limited depending on the pulse width setting.
Set the total rate and the pulse width so that the following conditions 1 and 2 are satisfied.
Otherwise, proper operation may not be assured.
Condition 1:
Flow rate span
*1
[m
3
/s]
Total rate [m
3
]
≤
1000 [Hz] [DO1 and DO2]
1 [Hz] [DO3]
Condition 2:
Flow rate span
*1
[m
3
/s]
Total rate [m
3
]
≤
1000
2
×
Total pulse width [ms]
*1) Full scale 1 or full scale 2, whichever is larger, in the case of auto 2 range, bi-directional range, and bi-directional
auto 2 range setting
The limitation of the maximum output frequency of each DO output port is applicable when the flow rate exceeds
the set range. Consequently, if the setting is made so that the maximum frequency is obtained at 100% flow rate,
the flow rate exceeding 100% does not allow the total pulse output to follow. If the over range continues for a long
time, accurate total value may not be obtained. If there is a possibility that the flow rate may exceed 100%, review
the range and the total rate, and make the setting so that the maximum frequency is kept below the limit.
Example of calculation
Find the total rate settable range under the following range and pulse width.
When the range and the pulse width settings are as follows:
Full scale: 36 [m
3
/h] (=0.01 [m
3
/s]), Pulse width: 50 [ms]
i) In the case of DO1/DO2
From condition 1
Total rate
≥
Flow rate span
*1
[m
3
/s]
Total rate [m
3
]
=
0.01 [m
3
/s]
1000 [Hz] = 0.00001 [m
3
] = 0.01 [L]
From the above: 0.01 [L]
≤
Total rate ....................................................................................................... A
