Within IEC 61850, protocols for the transmission of instantaneous voltage and current values are specified. The sensors used in the transmission process can be conventional CTs and VTs as well as unconventional current and voltage sensors.
A merging unit (MU) collects the measured current and voltage values from the current and voltage sensors. Then it merges the digitized values, which are called “Sampled Values” (SV), into a data stream published to the substation network.
Using this method, measured values (for example, the bus voltage for a busbar protection scheme) can easily be distributed to multiple bay devices.
The Omicron CPC 100 Multi-functional Primary Test System performs closed-loop testing whereby a test signal is injected on the primary side of the current / voltage sensors. The MU converts the sensor output into a SV stream which is published to the substation network. The CPC 100 then reads the data back from the network in order to perform a variety of different tests.
Automatic MU and channel detection is achieved by injecting a test signal with a specific wave form. An optimized and time-effective algorithm searches for the unique test pattern within all the available MUs on the network to identify the correct channel for testing.
The CPC 100’s SV test card operates according to the Implementation Guideline for Digital Interface to Instrumental Transformers using IEC 61850-9-2” published by the UCA International User Group.
Omicron CPC 100 Sampled Values testing
> SV CT ratio test and polarity check up to 800 A or up to 2 000 A , 5 kVA output power | with the CP CB2
> SV VT ratio test and polarity check up to 2 kVAC
> Automatic MU detection
> Automatic voltage / current channel detection
> Frequency selective voltage / current meter
> Noise level measurement
> Amplitude response of the signal processing chain up to 800 A or up to 2 kVAC | frequency from 15 Hz to 400 Hz
This is part of the Omicron CPC 100 All-In-One Test System Series. Check out the other posts!