Tecfluid FLOMID Series, Инструкция по эксплуатации

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7.5.3.1 4-20 mA output configuration
It allows to choose between unidirectional and bidirectional.
Programming a flow rate value for 20 mA higher than the one for 4 mA, the loop current
changes from 4 to 20 mA as the flow increases.
Otherwise, programming a flow rate value for 20 mA lower than the one for 4 mA, the
current loop will change from 20 to 4 mA as the flow increases.
7.5.3.3 Current calibration for 4 and 20 mA
The MX4 converter is delivered with the current output already calibrated. If you want to
correct a derive of the 4 or 20 mA current values because they do not coincide with the
ammeter used, it can be done by pressing the keys (Down / Left) and (Up) to increase or
decrease the current respectively in each case. The values shown on the screen are
reference levels. When one of this data is confirmed, the MX4 will take the current value
shown on the ammeter as a reference.
Before making a current calibration, be sure that the ammeter used for that is showing the
real measure.
7.6 Working screen
Flow rate, totalizer, liquid velocity or flow rate and totalizer screens can be programmed as a
default. Thus, the converter presents this screen when a power failure occurs or when
returning from the installation or programming menu.
If “Unidirectional” is chosen, the analog output will have a value proportional to the flow rate
when positive, and it will provide always 4 mA when negative.
If “Bidirectional” is chosen, the analog output will have a value proportional to the flow rate
for both positive and negative values.
7.5.3.2 Programming of the 4-20 mA output
Flow rate values equivalent to each current are entered directly.