Direct Input And Output Communications; Description - GE D60 Instruction Manual

DIRECT INPUT AND OUTPUT COMMUNICATIONS

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Using an amplitude-modulated receiver causes errors up to 1 ms in event time stamping.
When IRIG-B is used as the time synchronization source for synchrophasors, the DC level shifted option must be
used in order to achieve the 1% Total Vector Error specified by the standard. If amplitude modulated IRIG-B is used,
it results in a 20 to 25 degree error in the synchrophasor angle measurement. The IEEE 1588 Precision Time
Protocol can also be used to achieve accurate time synchronization for synchrophasor calculation.
3.4 Direct input and output communications

3.4.1 Description

The direct inputs and outputs feature makes use of the type 7 series of communications modules and allows direct
messaging between UR devices. The communications modules are outlined in the table later in this section.
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Figure 3-27: Options for the IRIG-B connection
D60 LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
CHAPTER 3: INSTALLATION