Ultraflux Uf 841, User Manual

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NT UF 841 CP GB (d) / June 2015
5) Relay output module
Each relay output may be configured according to one of the following operating modes:
•
Open:
The relay remains constantly off.
•
Closed:
The relay is on if the Uf 841 is powered on, and off if it is not powered on. This choice
therefore allows the relay to be used to detect the presence of the power supply (positive safety).
•
Totalizer: The relay generates a pulse with an adjustable width on each incrementation of the
selected totalizer.
The pulse width must then be defined, determining the time for which the relay remains closed (the
relay, initially off, is then on for half of the period, then off again for at least the same duration).
The value of the relay period must be less than the weight of the pulse divided by the flow rate.
Example:
Flow rate = 1000 l/s / Pulse weight = 100 l.
We therefore have 1 pulse every 100/1000 = 100 ms.
The value of the period must therefore not exceed 100 ms otherwise not all pulses emitted by the
totalizer will be counted.