ITALCOPPIE SENSORI DISPLAY L.P., Руководство пользователя

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IMB223 Rev.1.00 Oct. ‘21
Installation and operation
5 Installation and operation
5.1 Installation
The device is designed for switch panel mounting in a borehole of Ø22.5 mm (see Annex A for dimensional
drawings).
Carefully position the supplied gasket on the display rear surface. Insert the cylindrical part of the device into
the borehole and tighten the nut from the rear side of the switch panel. Connect the device to the signal ca-
ble in accordance with Annex B.
The device factory settings can be changed before assembly if necessary. For this purpose the display must
be connected to a standard signal 4 - 20 mA.
5.2 Operating mode
The operating mode is automatically switched on if the standard signal 4 - 20 mA is connected to the termi-
nals.
The input signal is digitalised, the square root calculated (if the function is enabled) and the signal according-
ly to the set parameters calibrated and displayed. The scale factor is calculated based on the parameter
di.Lo “lower limit” (according to input signal 4 mA) and di.Hi “upper limit” (according to input signal 20 mA).
If the input signal is lower than 3.8 mA, the error message Lo is displayed.
If the input signal is higher than 22.5 mA, the error message Hi is displayed.
Square root function
This function is intended for transmitters with square characteristic curve. To enable the function, the param-
eter
Sqrt
must be set to
ON
.
Damping function
Undesirable signal fluctuations can be suppressed through the adjustable filter constant.
The most important feature of the exponential filters is
τ
d – the filter time constant (parameter
td
) (see Fig. 3
and Table 2).
If the constant increases, the display reacts to changes of the input signal more slowly and the susceptibility
to interference is lower.
Fig. 2 Mounting 1