London Electronics Fusion Series, Детали подключения, масштабирование и общая информация

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InFlight Hi Alarm relay
Shutoff Valve
Loadcell platform
Inflight material
The In-Flight alarm modes are used in applications where you want to
accurately fill one container from another.
If you were to simply close the shutoff valve when the weight reaches
your desired amount, you would find thet the weight is higher than you’d
hoped for.
This is because some material is still in mid-flight when you send the
alarm signal to shut the valve, and the valve will take some time to fully
close.
The load measured on the loadcell platform will continue to increase
after the alarm signal is sent to the shutoff valve.
The InFlight modes subtract or add this “In-Flight” amount from the
setpoint to ensure that your final fill amount is as close as possible to
your desired value.
In automatic mode, the unit will note the error after the first fill and try to
correct for it on the next fill by moving the trip point by all the error amount
on the 2nd fill and by half the subsequent error amount on each
following fill. It will constantly monitor the error and correct by half that
amount, to ensure a smooth trend towards accurate filling.
Which mode should I use?
If your loadcells are mounted
under the container being
filled, as shown here, you
should use the
InFlight HI
mode, as the weight is
increasing on the loadcell
platform during filling.
Manual or Automatic ?
You can set a manual value for the Inflight amount, if you know how much in-flight material will continue to fall into the
container after the shutoff valve has been triggered, and if this value is likely to remain consistent from fill to fill.
If you don’t know the inflight amount or if the material flow properties may change from batch to batch, you can use the
automatic mode.
To set, press the alarm button until you illuminate the alarm LED channel you want to change. Press the alarm button
again for around 6 seconds, you will see “Set.Pt” followed by “AL CFG”. Use the Digit, UP/Down buttons and OK to set.
Manual Mode
Automatic mode
Set..P flgt
F L . H I
FL.HI A
Desired Setpoint
This is the amount
you want to fill.
Inflight amount
You can set a best
guess for automatic
mode, to speed the
correction.