
In the module you can combine some measurands to one data package (Frame), which
is transferred in one step. One data package consists of 12byte user data. Considering
the data length of 12 bytes, you can define the content of a frame by specifying the
ID
of
the measurands. Up to 256 frames may be configured (
Frame 0
...
Frame 255
). The fol-
lowing must be observed:
n
The definition of
Frame 1
to
Frame 255
happens by the command
Set_Frame
.
Chapter 3.27.7.2.3 ‘Set Frame’ on page 323
n
Frame 0
with the corresponding measurands can exclusively be specified by the par-
ametrization.
Chapter 3.27.5 ‘Parameter data’ on page 314
n
With telegram type
Zero Frame
the data package of Frame 0 can be accessed. After
the start-up of the module there are automatic
Zero Frame
requests as long as the
process data communication comes from the head module.
When defining frames by means of
‘Set Frame’
, via the
FR-ID
these are assigned to a
number between 0 ... 255. By specifying the
FR-ID
you can request the corresponding
frame.
In the following the data types are listed, which are used in the module. The length is to
be considered particularly by the definition of
Frames
.
Data type
Length in byte
Description
UINT_8
1
Integer 8bit
UINT_16
2
Integer 16bit
UINT_32
4
Integer 32bit
INT_8
1
Signed integer 8bit
INT_16
2
Signed integer 16bit
INT_32
4
Signed integer 32bit
FLOAT
4
32bit floating point IEEE 754
3.27.3.2
Principle of measurement
n
3-phase AC low-voltage networks are characterized by the following relationship:
–
Nominal voltage is the RMS voltage U
RMS
e.g. 230V
RMS
as star voltage between
one of the three phase conductors (L1, L2 or L3) and the neutral conductor N.
n
The module is used for detecting the current and voltage values and the energy
values of all 3 phases. Here, the module measures the real effective value (True
RMS) of voltages and currents.
n
The sampling rate of the digitally processed measured values is 2.7 kHz. The time
interval for the calculation of the actual values is 200 ms. This results in an evaluation
window of the measured data of 540 measured values, which can be requested at
any time.
Frame
FR-ID
Data type
Calculation of the effective
values of current and
voltage
VIPA System SLIO
Analog Input
031-1PA00 - AI1x 3Ph 230/400V 1A > Basics
HB300 | SM-AIO | | en | 17-05
310