![background image](http://html1.mh-extra.com/html/abb/relion-670-series/relion-670-series_applications-manual_3052129750.webp)
There are two sample rates defined: 80 samples/cycle (4000 samples/sec. at 50Hz or 4800
samples/sec. at 60 Hz) for a merging unit “type1” and 256 samples/cycle for a merging unit
“type2”. The IED can receive data rates of 80 samples/cycle.
Note that the IEC 61850-9-2 LE standard does not specify the quality of the sampled values,
only the transportation. Thus, the accuracy of the current and voltage inputs to the merging
unit and the inaccuracy added by the merging unit must be coordinated with the requirement
for actual type of protection function.
Factors influencing the accuracy of the sampled values from the merging unit are for example
anti aliasing filters, frequency range, step response, truncating, A/D conversion inaccuracy,
time tagging accuracy etc.
In principle the accuracy of the current and voltage transformers, together with the merging
unit, shall have the same quality as direct input of currents and voltages.
Section 23
1MRK 505 343-UEN B
Requirements
744
Application manual
Summary of Contents for Relion 670 series
Page 1: ...RELION 670 SERIES Line differential protection RED670 Version 2 1 IEC Application manual...
Page 2: ......
Page 40: ...34...
Page 64: ...58...
Page 150: ...144...
Page 406: ...400...
Page 472: ...466...
Page 494: ...488...
Page 512: ...506...
Page 524: ...518...
Page 604: ...598...
Page 686: ...680...
Page 718: ...712...
Page 722: ...716...
Page 758: ...752...
Page 759: ...753...