Product Overview

The 3300/48-01-01-00-00 is a dedicated single-channel instrument designed to measure the absolute thermal growth of a machine's casing relative to its foundation. Unlike differential expansion which tracks internal clearances, this Case Expansion Monitor provides critical data on how the outer structure of large steam turbines or high-temperature machinery responds to thermal cycles. By utilizing Linear Variable Differential Transformers (LVDTs), the module converts mechanical displacement into precise electrical signals, ensuring that the machine frame expands freely on its sliding feet. This prevents "cocking" or binding that could lead to severe internal misalignment and subsequent mechanical damage.

Essential Hardware Parameters

• Measurement Channel: Single-channel absolute expansion monitoring

• Full-Scale Range: 0 to 25 mm (Option 01)

• Transducer Interface: Compatible with standard LVDT inputs (Option 01)

• Alarm Relay Type: Epoxy-sealed relays for industrial reliability (Option 00)

• Safety Certification: No specific agency approval required for this configuration (Option 00)

• Signal Accuracy: Within ±1.6% of full-scale value

• Front Panel Display: 83 mm (3.25 inches) vertical digital readout

• Net Weight: 1.15 kg (2.54 lbs)

• Physical Footprint: 241 mm x 50 mm x 103 mm (9.5 in x 1.97 in x 4.05 in)

Engineering Deployment Scenarios

This monitoring system is a staple in power generation and heavy industry where massive thermal shifts are part of daily operations. Key implementations include:

• Base-Load Steam Turbines: Tracking casing expansion to ensure sliding feet are properly lubricated and moving freely.

• Large Gas Turbines: Monitoring structural integrity during rapid startup and shutdown cycles.

• High-Pressure Boiler Feed Pumps: Detecting uneven growth that could strain connected piping.

• Industrial Drying Kilns: Measuring outer shell displacement in paper and textile manufacturing.

• Combined Cycle Power Plants: Integrating case expansion data into a centralized machinery protection strategy.

FAQ

Q: What is the primary difference between Case Expansion and Differential Expansion?

A: Case expansion measures the absolute growth of the machine housing relative to the floor, whereas differential expansion measures the relative growth between the rotor and the casing.

Q: Why does this 3300/48 model utilize an LVDT instead of a proximity probe?

A: LVDTs are better suited for measuring the large, slow mechanical movements associated with casing expansion, typically covering ranges up to 25mm or more, which exceeds the capability of standard proximity sensors.

Q: Is this module compatible with the 3300/01 System Monitor?

A: Yes, as a standard 3300 series component, it communicates via the rack backplane with the system monitor for power and global alarm status.

Q: Can this unit be used in hazardous environments?

A: This specific configuration (Option 00) does not include internal safety barriers or CSA/ATEX approvals. For hazardous zones, external zener barriers must be integrated into the signal loop.

Q: How do I verify the module is functioning correctly without a machine shutdown?

A: The monitor features a front-panel "OK" LED and self-diagnostic circuitry that continuously verifies the integrity of the LVDT input and internal processing logic.