Bently Nevada 3300/45 Dual Differential Expansion Monitor

The 3300 system has been enhanced to upgrade the computer/communications interface options. The 3300/03 SDI/DDI communication protocols were released in April 1992 with external SDIX/DDIX, TDIX and TDXnet™ communication processors released in August 1992, July 1993 and December 1997, respectively. The internal Transient Data enabled (TDe) communications processor was released in July 2004. 3300 components that have been changed to implement these interface options are the System Monitor, AC and DC Power Supply, Rack Backplane, and individual monitor firmware. 3300 systems that consist of all the upgraded components are referred to as an SDI/DDI system or TDe system. The SDI/DDI system uses the 3300/03 System Monitor and the TDe system uses the 3300/02 System Monitor.

The information in this guide is divided into these two sections:

Section 2, System Identification, lists the four configurations of the 3300 Monitoring System which are authorized by Bently Nevada LLC and shows how to identify each one. Identifying your system will help you make decisions about replacement parts and computer/communications interfaces.

Section 3, System Compatibility, describes the compatibility between 3300 systems, communication interfaces, and monitoring and diagnostic software

Differential Expansion is the measurement of the axial position of the rotor with respect to the machine casing at some distance from the thrust bearing. Changes in axial position relative to the casing affect axial clearances and are usually the result of thermal expansion during startup and shutdown. The measurement is typically made with a proximity probe transducer mounted to the machine casing and observing an axial surface (e.g., collar) of the rotor. The measurement is usually incorporated as part of a Turbine Supervisory Instrumentation system. The 3300/45 Dual Differential Expansion Monitor provides two channels of continuous differential expansion monitoring. Both the magnitude and direction of differential expansion are monitored. Four alarm setpoints (two over and two under alarms) can be set for each channel. Channel B of the monitor can be turned OFF for machines requiring the measurement at only one location.

Ordering Information For spares, order the complete catalog number as described below. This includes a front panel assembly, monitor PWAs with sheet metal, and appropriate relay module. This unit is optioned, tested and ready to install in your system.