User`s manual
Table Of Contents
- 1. Introduction
- 2. Getting Started
- 3. Featured Functions
- Configuring Basic Settings
- Using Port Trunking
- Configuring SNMP
- Using Communication Redundancy
- Using Traffic Prioritization
- Using Virtual LAN
- Using Multicast Filtering
- Using Bandwidth Management
- Using Port Access Control
- Using IP Filter
- Using Auto Warning
- Using Line-Swap-Fast-Recovery
- Using Set Device IP
- Using Diagnosis
- LLDP
- Using Monitor
- Using the MAC Address Table
- Using System Log
- Using HTTPS/SSL
- A. MIB Groups
- B. Specifications
- C. Modbus/TCP Map

PT-7728 User’s Manual Featured Functions
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Configuring IEEE 1588/PTP
Time synchronization may be accomplished using the IEEE Standard for a Precision Clock
Synchronization Protocol for Networked Measurement and Control Systems (IEEE
1588-2008) to synchronize real-time clocks incorporated within each component of the electrical
power device in power automation applications. For IEC 61850-9 operations, digital CTs and PTs
provide measured values of current and voltage through MUs to bay level IEDs with the process
bus. In any given system there may be a great number of MUs operating at once. These different
streams of sampled values must be accurately time-synchronized before they can be used.
SNTP is able to provide synchronization accuracy within about 1 ms. However, this is not precise
enough for raw data sampled values. Moxa’s PT-7728-PTP IEC 61850-3 fast Ethernet switches
support the latest version of IEEE 1588 v2 technology to fulfill precise time synchronization
requirements for protection and control applications. These Ethernet switches guarantee
time-stamping accuracy within 1 μs for the IEC 61850 process layer. They can be configured for
1558 v2 Master, Boundary Clock, and Transparent Clock functionality.
The following diagram shows a basic IEEE 1588 application hierarchy for substation automation.