SR469-P5-HI-A1-E Application Protection Device

Description

The 469 is equipped with 3 fully functional and independent communications ports. The front panel RS232 port may be used for 469 setpoint programming, local interrogation or control, and upgrading of 469 firmware. The Computer RS485 port may be connected to a PLC, DCS, or PC based user interface program. The Auxiliary RS485 port may be used for redundancy or simultaneous interrogation and/or control from a second PLC, DCS, or PC software.

All 469 features are standard; there are no options. The phase CT secondaries, control power, and analog output range must be specified at the time of order. The 469 differential CT inputs are field programmable for CTs with 1 A or 5 A secondaries. There are two ground CT inputs, one for the GE Power Management 50:0.025 core balance CT and one for a ground CT with a 1 A or 5 A secondary, also field programmable. The VT inputs will accommodate VTs in either a delta or wye configuration. The output relays are always non-failsafe with the exception of the service relay. The 469PC software is provided with each unit. A metal demo case may be ordered for demonstration or testing purposes.

The 469 is packaged in the standard GE Multilin SR series arrangement, which consists of a drawout unit and a companion fixed case. The case provides mechanical protection to the unit and is used to make permanent connections to all external equipment. The only electrical components mounted in the case are those required to connect the unit to the external wiring. Connections in the case are fitted with mechanisms required to allow the safe removal of the relay unit from an energized panel (for example, automatic CT shorting). The unit is mechanically held in the case by pins on the locking handle that cannot be fully lowered to the locked position until the electrical connections are completely mated. Any 469 can be installed in any 469 case, except for custom manufactured units that are clearly identified as such on both case and unit, and are equipped with an index pin keying mechanism to prevent incorrect pairings.

The impact of fieldbus on traditional dcs comes from its essentially superior technical characteristics over dcs systems. According to the definitions of the International Electrotechnical Commission IEC and the Fieldbus Foundation FF, fieldbus technology has the following five main characteristics:
① Digital signals completely replace 4-20mA analog signals;
② Complete the distribution of basic process control, alarm, and calculation functions on site;
③ Add non control information to the device, such as self diagnostic information, configuration information, and compensation information;
④ Realize the unity of on-site management and control;
⑤ Truly achieve system openness and interoperability.

Fieldbus technology is not only a communication technology, but actually incorporates the essence of technologies such as intelligent instruments, computer networks, and Open Systems Interconnection (OSI). All of these characteristics make the fieldbus control system (FCS) based on fieldbus technology have significant advantages over traditional dcs systems:
① The system structure is greatly simplified, and the cost is significantly reduced;
② Strengthen the autonomy of on-site equipment and comprehensively improve system performance;
③ Improved the reliability and accuracy of signal transmission;
④ Truly achieving a fully decentralized and fully digital control network;
⑤ Users always have system integration rights.
These advantages can be verified by comparing the network structures of dcs and fieldbus systems.