Product Description

Overview

The A6740 from EPRO (MMS 6000 series) is a high-reliability, 16-channel Output Relay and Case Expansion Monitoring Module. It is engineered to provide accurate casing displacement measurement and versatile relay control for industrial machinery. The module is ideal for steam turbines, compressors, and large rotating equipment, offering precise monitoring of thermal growth and machine protection logic during startup, operation, and shutdown phases.

Key Features

• Dual-Channel Measurement: Supports two independent channels for redundant or dual-sided turbine casing monitoring

• 16 Configurable Relays: Selectable as Normally Open (NO) or Normally Closed (NC), with adjustable energization and time delay up to 30 seconds

• Advanced Logic Functions: Supports AND, OR, 2-out-of-3, and complex logic expressions up to 30 per module

• Sensor Compatibility: Accepts LVDTs or inductive displacement transducers for high-resolution casing expansion measurement

• Signal Outputs: Two 0/4–20 mA analog outputs for DCS integration; relay outputs for alarms and fault detection

• Hot-Swappable Design: Can be replaced without interrupting operation of the MMS 6000 rack

• Robust Industrial Design: Galvanically isolated inputs/outputs, IP00 module rating, IP20 front panel, vibration and shock resistant

Technical Specifications

Applications

• Turbine Case Expansion Monitoring: Measures axial and radial growth during startup or shutdown

• Machine Protection: Detects uneven expansion (“crabbing”) to prevent mechanical stress or rubbing

• Alarm & Control Logic: Configurable relay outputs for alert, danger, or maintenance triggers

• Redundant Safety Systems: Dual-channel design ensures continuous monitoring even if one sensor fails

FAQ

Q: Can the A6740 module operate without interrupting other MMS 6000 modules?
A: Yes, it is hot-swappable and can be replaced without downtime.

Q: What sensors are compatible with this module?
A: Linear Variable Differential Transformers (LVDTs) and inductive displacement transducers.

Q: How precise is the measurement?
A: Typically ±1% of full scale, capable of detecting millimeter-level casing movements.

Q: Can the relay logic be customized?
A: Yes, up to 30 logic expressions can be defined, including AND, OR, 2-out-of-3, and complex sequences.

Q: What types of outputs are available?
A: Two analog 0/4–20 mA outputs plus 16 configurable relays for alert, danger, and OK monitoring.