Electro-Voice 250, 1252 operation manual Five Modes of Time Synchronization

5.22: Five Modes of Time Synchronization

The Nexus meter offers up to five modes of Time Synchronization, depending on options selected at the time of ordering.

1.Internal Crystal: The Default Time Constant is an Internal Crystal. The crystal is accurate to approximately 1 minute per month.

2.Line Frequency: The meter ignores the internal crystal and counts frequency to synchronize the clock. This feature is highly accurate in the presence of reliable system frequency. If power is lost, the unit automatically switches to the internal crystal.

3.Modbus Commands Time Synchronization: The meter uses Serial Modbus-Based Commands to change the date and time of the clock. The meter relies upon the Internal Crystal between synchronization intervals. This mode is used in conjunction with MV90.

4.DNP Line Synchronization: The meter uses DNP Protocol Commands to change the date and time of the clock. The meter relies upon the Internal Crystal between synchronization intervals.

5.IRIG-B:The meter uses a Signal Generating Device connected to the GPS Satellite System to synchronize Nexus Time. This mode is accurate to within one millisecond. This mode is detailed in section 5.23.

Electro Industries/GaugeTech Doc #: E107706 V1.25 5-24