LVDTs for gas turbine systems are generally externally mounted designs, either “block” or “bulkhead” mounted and usually single or dual feedback A devices. The 4-wire designs have a 37-degree lead angle fitting per SAE standard “AS4395G06” as an exit closure for the wire conduit.

The various designs include all stainless steel sealed housings that add to the robust quality of the devices, for use in Zone 2, Hazardous areas.

Specific production designs are currently certified to the following specification levels:

• Factory Mutual approved for Intrinsically Safe, Non-Incendive applications.
• IEC-CENELEC approved for Non-Incendive, Ex N IIC T3 applications.
• IEC-CENELEC approved Non-Incendive, Ex N IIC T3,
  ETL Certified to CAN/CSA C22.2 No. 213,
  ETL Certified to UL Standard 1604.

ATEX Compliant: Equipment Group II, Category 3 for use in Zone 2 applications.

Typical Performance Parameters:

• Excitation Voltage: 7.0 VRMS
• Excitation Frequency: 3000 Hz
• Electric Stroke: 0.5" to 11.0"
• Wave Form: Sine
• Power Apparent: 1.0 VA Max.
• Load: 10K Ohms
• Linearity: ±1.0%
• Temperature Range: -100°F to +350°F
• Signal Output: +0.7 VRMS to 3.5 VRMS

Data Sheet / LVDT /

Note: Voltage range is constant for any stroke.
Only the sensitivity changes (v/V/Inch)

In addition to LVDTs, Kavlico also supplies “Rotary Variable Differential Transformers” (RVDTs) in both single and dual tandem configurations for power plant use.

This design group has been certified for:

• North America: Class I, Division 2, Groups A-D
• Europe: Eex nV II T3, SIRA 99Y4045X
• ETL Certified to CAN/CSA C22.2 No. 213
• ETL Certified to UL Standard 1604

Data Sheet / RVDT /

These RVDTs can be upgraded to an Intrinsically Safe level by use of a Barrier Circuit Interface between the sensor and the power Source.

Caution Note: It is the responsibility of the system installer to review the need for any intrinsic safety barrier to limit the transfer of energy between the interface equipment and the RVDTs and LVDTs.

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Feedback control sensors for steam turbine applications utilize a slightly different winding design, using on 3-wires and are described as “Variable AC Impedance sensors.” These devices have a 1/8-14 NPT fitting as an exit closure for the wire conduit or a PT-02H-14-5P type connector and can either be “blocked” or “bulkhead” mounted.

The various designs include all stainless steel sealed housings that add to the robust design of the overall device. When used with a Kavlico Carrier Demodulator, P/N GM 6244, specific designs can be considered as having a power and current limiting device per NEC Class 2.

Many production designs are currently certified to the following specification levels:

• UL Listed (219Y)
• Telemetering Equipment for Hazardous Locations,
• Class I, groups B, C, and D.

Typical Performance Parameters:

• Excitation Voltage: 3.0 VRMS to 24VRMS
• Excitation Frequency: 60 Hz to 3000 Hz
• Electrical Stroke: +0.75" to +26.0"
• Linearity: ±0.2% Full Stroke / ±1.5% @ 110% Full Stroke
• Temperature Range: -100°F to +300°F

Data Sheet / LVDT /