ABB Relion RES670, Technical Manual

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23.2.14 GPS time synchronization module (GTM)
IP15586-1 v2
23.2.14.1 Introduction
M14851-3 v4
This module includes a GPS receiver used for time synchronization. The GPS has one
SMA contact for connection to an antenna. It also includes an optical PPS ST-
connector output.
23.2.14.2 Design
M14856-3 v5
The GTM is a PCMIP-format card and is placed only on one of the ADM slots. The
antenna input connector is shielded and directly attached to a grounded plate to
eliminate the risk of electromagnetic interference.
All communication between the GTM and the NUM is via the PCI-bus. PPS time data
is sent from the GCM to the rest of the time system to provide 1μs accuracy at
sampling level. An optical transmitter for PPS output is available for time
synchronization of another relay with an optical PPS input. The PPS output connector
is of ST-type for multimode fibre and could be used up to 1 km.
23.2.14.3 Monitored data
PID-6200-MONITOREDDATA v2
Table 668: SYNCHGPS Monitored data
Name Type Values (Range) Unit Description
NoOfSatellites INTEGER - - Number of GPS signals from
satellites
23.2.14.4 Technical data
SEMOD55668-1 v1
SEMOD55660-2 v3
Table 669: GPS time synchronization module (GTM)
Function Range or value Accuracy
Receiver – ±1µs relative UTC
Time to reliable time reference with antenna in new
position or after power loss longer than 1 month
<30 minutes –
Time to reliable time reference after a power loss
longer than 48 hours
<15 minutes –
Time to reliable time reference after a power loss
shorter than 48 hours
<5 minutes –
Section 23
1MRK 511 408-UUS A
IED hardware
848 Phasor measurement unit RES670 2.2 ANSI
Technical manual