CHAPTER 3: INSTALLATION
DIRECT INPUT AND OUTPUT COMMUNICATIONS
N60 NETWORK STABILITY AND SYNCHROPHASOR MEASUREMENT SYSTEM – INSTRUCTION MANUAL
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Figure 3-26: Options for the IRIG-B connection
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.
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.