Valve Position transducer

Description

A complete Turbine Supervisory Instrumentation System (TSI) should include measurement of governor valves on the steam turbine. By measuring the opening of these valves, the amount of steam flowing to the individual valves in the group can be monitored and adjusted to provide highest machine operating efficiency. The 18639 Valve Position Transducer consists of an AC Linear Variable Differential Transformer (LVDT) that connects to the governor valve and measures valve opening. The LVDT has an internal nickel-iron core that moves in and out of a stainless steel casing. This casing contains primary and secondary coils that provide an electrical output based on the position of the core. The AC LVDT Valve Position Transducer system needs to be attached to the 3500/45 Position monitor or the 3300/70 Dual Valve Position Indicator to measure valve position. The one, two, and four inch models can also measure steam turbine case expansion for high temperature applications when used with the 3500/45 monitor. A core connecting rod may be necessary to link up with a flange on the governor valve. It is made of aluminum and available in six lengths.

Specifications

Electrical Linearity: 0.25% of full-scale Null Voltage: 0.5% of full-scale, maximum Environmental Limits Operating Temperature: -54 C to +149 C (-65 F to +300 F) Mechanical Height: 50.8 mm (2.0 in) Option -04 has a height of 69 mm (2.7 in).
For Reference Only – See Document #141597 Page 1 of 3