SATEC EM920 Operation Manual - Manual (Page 130)

Chapter 5 Configuring the EM920
Configuring Communication Protocols
130 EM920 Power Quality and Revenue Meter
3 The total number of AI, BI and BC change event points may
not exceed 64. When you change the number of the change
event points in the device, all event setpoints are set to defaults
(see Configuring DNP Event Classes below).
Scaling 16-bit AI objects
Scaling 16-bit AI objects allows accommodating native 32-bit
analog input readings to 16-bit object format; otherwise it
may cause an over-range error if the full-range value exceeds
a 16-bit point limit.
Scaling is enabled by default. It is not applied to points that
are read using 32-bit AI objects.
Refer to the EM920 DNP3 Reference Guide for information on
the data point scales and on a reverse conversion that should
be applied to the received scaled values.
Scaling 16-bit Binary Counters
Scaling 16-bit Binary Counters allows changing a counter unit
in powers of 10 to accommodate a 32-bit counter value to
16-bit BC object format.
If the scaling unit is greater than 1, the counter value is
reported being divided by the selected scaling unit from 10 to
1000. To get the actual value, multiply the counter reading
by the scaling unit.
Configuring DNP Class 0 Response
The most common method of getting static object
information from the device via DNP is to issue a read Class 0
request. The EM920 allows you to configure the Class 0
response by assigning ranges of points to be polled via Class
0 requests.
To view the factory-set DNP Class 0 assignments or build
your own Class 0 response message:
1. From the Meter Setup menu select Protocol Setup and
click on the DNP Class 0 Points tab
2. Select the object and variation type for a point range.
3. Specify the start point index and the number of points
in the range. Refer to the EM920 DNP3 Reference
Guide for available data points.
4. Repeat these steps for all point ranges you want to be
included into the Class 0 response.
5. Click Send to download your setup to the device.
The factory-set Class 0 point ranges are shown in the picture
below.