3B Scientific 3B NETlab™ - Manual (Page 5)

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5.1.2 Measurement functions:
5.1.2.1 Establishing and testing a connection:
In the first row of the upper left hand control panel
(Input control panel) in the measurement lab win-
dow, it is possible to enter the name of the connec-
tion by which the 3B NETlog™ is linked to the com-
puter by using the “…” button. This setting need
only be modified in exceptional cases. Normally, it
is set to “USB”. By clicking the “Test” button, the
connection can be tested and the result is dis-
played after a brief pause.
5.1.2.2 Selection of inputs:
Selection of the inputs required for measurements
can also be carried out in the top left control panel.
Clicking “Select” opens a dialog box, in which the
desired inputs can be specified. The following op-
tions are available:
Analog input A: used for measuring voltage, cur-
rent or other quantities in conjunction with a sen-
sor box which can be connected via the input at
the side.
Analog input B: used for measuring voltage or
other quantities in conjunction with a sensor box
which can be connected via the input at the side.
Digital inputs: the four digital inputs of the
3B NETlog™ unit are integrated together in an 8-pin
mini DIN connector on the right and designated A,
B, C and D. It is possible to interpret the inputs in
any of the following ways:
• As individual signals (A, B, C or D)
• An OR of all four signals (1 if at least one of the
signals is HIGH)
• The binary number represented by the signals
(“D/A conversion”, 1•A + 2•B + 3•C + 4•D)
Manual input: by selecting this input type it is
possible to enter a value into the data record
manually.
Time: a pulse signal at any of the digital or analog
inputs can be processed to determine information
about the pulse with regard to its timing. A value is
recorded for every pulse.
• Pulse time: elapsed time from the beginning of
the measurement to the rising edge of the cur-
rent pulse.
t
0
• Puls duration: elapsed time between the rising
edge and the falling edge of the current pulse.
t
• Pulse distance (- +): elapsed time between the
falling edge of the previous pulse and the ris-
ing edge of the current pulse.
t
• Pulse distance (+ +): elapsed time between the
rising edge of the previous pulse and the rising
edge of the current pulse.
t
Frequency: measures the mean frequency or dura-
tion of a periodic signal at an analog or digital
input over an interval specified by the user (the
start and end of the interval are specified by acti-
vating a button.)
5.1.2.3 Configuration of inputs:
The selected inputs appear in a list at the top of the
control panel. In order to configure a specific in-
put, select it and click “Config”. A dialog box ap-
pears which provides various options depending on
the selection:
Analog inputs:
• Symbol/Name and description: this makes it
possible to rename an input (e.g. correspond-
ing to the quantity which will be measured)
and also allows a description to be entered, if
needed, that should follow a semicolon.
• Input mode: selects between sensor (for use
with an external sensor box), DC voltage (VDC),
rms AC voltage (VAC), DC current (IDC, analog
input A only) and rms AC current (IAC, analog
input A only) measuring modes.
• Input range: selection of input range (measur-
ing range)
• Use prefix for displaying values: this makes it
possible to display measured values, large or
small, with prefices in front of the unit instead
of expressing them in powers of 10.
Digital inputs:
• Input mode: selects between displaying the
signal for a single input (digital signal A, digital
signal B, …), the result of ORing all four signals
(arbitrary digital signal) or the binary number
represented by the four signals (D/A conver-
sion, MSB: D).
Time/frequency:
• Input mode: selects the input where the pulse
signal is to be measured. The following selec-
tions are possible: digital input A, an OR of two