Nokeval 2012 User Manual page 18

digital converter. The factory-adjusted
calibration values are used to convert the
result to an accurate mA or V reading. This
unprocessed reading can be seen in the
monitor menu, item Mea.
If the digital lowpass filter is enabled, the
reading is processed with it. Likewise if the
Hold function is active, the reading is locked.
The reading is scaled using up to ten user-
entered scaling points Mea/Sca to a scaled
(engineering) reading. If the tare function is
active, the current tare value is subtracted.
The current value is copied to the tare value
memory when a switch programmed as a
Configuration menu
*+^
Master
>
Slot A
^
v
Slot B
Slot C
In/Setup/Range
Defines the physical input signal type.
Contains predefined ranges 0-20mA, 4-
20mA, 0-5V, and 0-10V, and free scaling
ranges mA, V, and Pot (=potentiometer).
Predefined ranges
When using one of the predefined ranges 0-
20mA, 4-20mA, 0-5V, or 0-10V, the scaling
to engineering units is done by giving the
scaled endpoints in menu items Lo and Hi.
When the input signal is at the low end of the
range, the scaled (displayed) reading
corresponds to Lo setting.
Free scaling
When using free scaling ranges mA, V, or
Pot, the In/Setup/Pts setting defines how
many scaling points are desired. It can be
adjusted from 0 to 10.
>
In Setup
Filter
^
v
More
Tare
tare switch is activated. The tare value is
stored in an EEPROM memory and is
retained even if the power supply is cut off.
The last element in the chain is Dead zone.
It allows rounding very small readings to
zero, to get a empty weigh to indicate zero
reading despite of a small tare error.
The reading processed this way is
observable in the monitor menu item Sca,
and it is also stored to the channel table to
be used on the display and analog and serial
outputs and alarms. The card in slot A stores
the reading to channel 1 and card in slot B to
channel 2.
>
^
v
Lopass
Disable
Dead
Hold
Act
Value
If 0 points is selected, the reading is not
scaled at all, but milliamps or volts are
displayed as are. A potentiometer will give
unscaled readings 0 to 100.
Two point scaling is achieved by setting Pts
to 2. Settings Mea1, Sca1, Mea2, and Sca2
will appear in the menu. Mea1 and Sca1
form a pair: when the physical input signal
corresponds to Mea1, the scaled
(engineering) reading will be Sca1. The
same applies for the other pair, and linear
interpolation and extrapolation is used
elsewhere.
An example how to scale 4-20mA signal to
be displayed 0-100::
Pts=2
Mea1 = 4 (mA)
Sca1 = 0 (scaled)
Mea2 = 20 (mA)
Sca2 = 100 (scaled)
A non-linear behaviour is obtained by using
more than two points. The points can be
18
Range
Visible when Range
Lo
is 0-20mA, 4-20mA,
Hi
0-5V, or 0-10V.
Pts
Mea1
Visible, when
Sca1
Range is mA, V, or
Pot.
Mea2
Sca2
MeaMin
Dec