Sntp Protocol - GE 845 Instruction Manual

DEVICE

SNTP Protocol

4–16
is 9000 ns and that the delay from the switch to the relay is 11000 ns, then the mean
delay is 10000 ns, and the path delay asymmetry is +1000 ns.
STRICT POWER PROFILE
Range: Enabled, Disabled
Default: Enabled
Power profile (IEEE Std C37.238™ 2011) requires that the relay select as a grandmaster
only power profile compliant clocks, that the delivered time have a worst-case error of
±1 µs, and that the peer delay mechanism be implemented. With the strict power profile
setting enabled, the relay selects as master only clocks displaying the IEEE_C37_238
identification codes. It uses a port only when the peer delay mechanism is operational.
With the strict power profile setting disabled, the relay uses clocks without the power
profile identification when no power profile clocks are present, and uses ports even if
the peer delay mechanism is non-operational.
The setting applies to all of the relay's PTP-capable ports.
PTP DOMAIN NUMBER
Range: 0 to 255
Default: 0
The setting is set to the domain number of the grandmaster-capable clock(s) to which
they can be synchronized. A network may support multiple time distribution domains,
each distinguished with a unique domain number. More commonly, there is a single
domain using the default domain number zero.
The setting applies to all of the relay's PTP-capable ports.
PTP VLAN PRIORITY
Range: 0 to 7
Default: 4
The setting selects the value of the priority field in the 802.1Q VLAN tag in request
messages issued by the relay's peer delay mechanism. In compliance with PP (Power
Profile) the default VLAN priority is 4, but it is recommended that in accordance with PTP
it be set to 7.
Depending on the characteristics of the device to which the relay is directly linked, VLAN
Priority may have no effect.
The setting applies to all of the relay's PTP-capable ports.
PTP VLAN ID
Range: 0 to 4095
Default: 0
The setting selects the value of the ID field in the 802.1Q VLAN tag in request messages
issued by the relay's peer delay mechanism. It is provided in compliance with PP (Power
Profile). As these messages have a destination address that indicates they are not to be
bridged, their VLAN ID serves no function, and so may be left at its default value.
Depending on the characteristics of the device to which the relay is directly linked, VLAN
ID may have no effect.
The setting applies to all of the relay's PTP-capable ports.
PTP PRIORITY
Range: 1, 2
Default: 1
The setting sets the priority of PTP time for the relay. If set to 1 and IRIG-B is available,
the relay syncs the relay's time reference to the PTP time. If set to 2 and IRIG-B is
available, the relay syncs its reference to IRIG-B time.
Path:
Setpoints > Device > Real Time Clock > SNTP
845 TRANSFORMER PROTECTION SYSTEM – INSTRUCTION MANUAL
CHAPTER 4: SETPOINTS