Emerson Series 3000 MVD Manuel D’Utilisation
72
Micro Motion
®
Series 3000 MVD Transmitters and Controllers
Configuring Outputs
The resulting Frequency value must be within the range of the frequency output (0 to 10,000 Hz).
•
If the Frequency value is less than 1 Hz, reconfigure the receiving device for a higher
pulses/unit setting.
pulses/unit setting.
•
If the Frequency value is greater than 10,000 Hz, reconfigure the receiving device for a lower
pulses/unit setting.
pulses/unit setting.
8.5.2
Maximum pulse width
The frequency output maximum pulse width defines the maximum duration of the “active” portion of
the wave that the Series 3000 device sends to the frequency receiving device. The active portion may
be the high voltage or 0.0 V, depending on the polarity setting, as shown in Figure 8-3.
the wave that the Series 3000 device sends to the frequency receiving device. The active portion may
be the high voltage or 0.0 V, depending on the polarity setting, as shown in Figure 8-3.
Figure 8-3
Pulse width
Maximum Pulse Width can be set to 0, or to values between 0.5 and 277.2352 milliseconds. The
user-entered value is adjusted automatically to the nearest valid value. If Maximum Pulse Width is set
to 0, the output will have a 50% duty cycle, independent of the output frequency. A 50% duty cycle is
illustrated in Figure 8-4.
user-entered value is adjusted automatically to the nearest valid value. If Maximum Pulse Width is set
to 0, the output will have a 50% duty cycle, independent of the output frequency. A 50% duty cycle is
illustrated in Figure 8-4.
Example
Maximum appropriate flowrate (Flow) is 2000 lbs/min.
Receiving device is configured for 10 pulses/pound.
Solution:
Series 3000 device configuration:
•
Frequency = 333.33
•
Flow = 2000
Frequency
Flow
T
------------
N
×
=
Frequency
2000
60
-------------
10
×
=
Frequency
333.33
=
Pulse width
Polarity = Active High
Polarity = Active Low
Pulse width