6 Commissoning, operation
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WIKA operating instructions digital indicator DI30
6.6 Description of device parameters
The DI30 has a number of unit parameters with which the function of the
indicator can be adjusted to the relevant measuring tasks. Because of the
large number of these settings and the limited possibility of displaying them
on the 7-segment display, the parameters have been given consecutive
numbers. (see chapter “6.7 Program Number Table”)
PN0: Measuring input
One of the aspects in the basic configuration is the desired measuring input,
which consists of the terminal selection and the relevant factory or sensor
calibration.
PN1 and PN2: Scaling
The two program numbers 1 and 2 are used to scale the indication. With
these two parameters the end value and start value are parameterised. If
sensor calibration has been selected via PN0 = 0, then the current for the
relevant sensor signal must be applied during programming. Otherwise, a
simple allocation of the selected input configuration will be made. For
example, at PN0 = 3, which corresponds to a standard signal input 0 … 10 V,
the value saved under PN1 will be indicated at 10 V, and the value saved
under PN2 will be indicated at 0 V.
PN3: Decimal point
By changing this parameter the number of places shown after the decimal
point in the display is changed. This parameter has no influence on the
scaling of the indication value, only on the position of the decimal point in the
display.
PN5: Offset shift
With this parameter it is possible to carry out a parallel shift of the
parameterised characteristic line. This may be necessary, if for example a
pressure transmitter ages over the course of time, giving rise to a shift in the
zero point. With the parallel shift the transmitter can be adjusted back to the
zero point. Another application is to parameterise a certain tank level to zero
and have any deviation from this level displayed.
PN10: Zero point suppression
Via the zero point suppression, an indication value window can be defined as
zero. This means, for example, that at PN10 = 10, all indication values
between –10 … +10 are shown in the display as zero. This function is
intended to produce a reliable zero indication at high display resolution and
low sensor accuracy around zero. This could be, for example, the rpm of an
engine for which a zero would be expected in the display when standing still.
