Azbil MagneW Two-wire PLUS+ MTG15A, User Manual

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2. DUTY 50% (Automatically set)
Selecting DUTY 50% automatically sets the pulse width as follows:
Calculation method 1
Make calculations to obtain a pulse width that is DUTY 50% of the span frequency. The
pulse width is automatically set. In this case, the calculated value of the pulse width does
not appear on the display.
Calculation method 2
In addition, if the pulse width calculated by the calculation method 1 exceeds 1 second,
the pulse width is set to 1 second.
Calculation method 1: When the range is 360 m 3 /h, and pulse scale is 2 l/P,
First convert the unit of range to calculate the span frequency.
Convert the range into the unit of per-second (/s).
360 m 3 /h

0.1 m 3 /s
Convert the unit of flow rate range to be same as the unit of pulse scale.
0.1 m 3 /s

0.1 × 1000 l/s
100 l/s
Calculation of span frequency
(100 l/s) / (2 l/P)
= 50 Hz
50 Hz

20 ms (= A)
Calculation of pulse width where the DUTY ratio is equivalent to 50%
B = 0.5 × A
= 0.5 × 20 ms
= 10 ms
Therefore, the pulse width is 10 ms.
Calculation method 2: When the range is 36 m
3 /h, and pulse scale is 100 l/P,
First convert the unit of range to calculate the span frequency.
Convert the range into the unit of per-second (/s).
36 m
3 /h

0.01 m 3 /s
Convert the unit of flow rate range to be same as unit of pulse scale.
0.01m 3 /s

0.01 × 1000 l/s
10 l/s
Calculation of span frequency
(10 l/s) / (100 l/p)
= 0.1 Hz
0.1 Hz

10 s (= A)
Calculation of pulse width where the DUTY ratio is equivalent to 50%
B = 0.5 × A
= 0.5 × 10 s
= 5 s
Because the calculated pulse width exceeds 1 s, it takes 1s.