Temperature measuring system VTI-GL-100C

fiber opticcontinuousfor industrial applications

Overview
Thermal monitoring in large-scale energy and industrial assets requires 100% continuous coverage with zero blind spots, meter-level event localization, and resilience to harsh environments.

Key Performance Indicators

• Total measurement range: 4 optical channels × 5 km per channel (20 km continuous)
• Temperature accuracy: ±1 °C; temperature resolution 0.1 °C
• Spatial resolution: 0.5 m
• Field power along route: 0 W (passive optical cable)
• EMI/RFI immunity: total immunity to electromagnetic interference

Unmatched Advantages

• 24/7 continuous monitoring along fiber to avoid blind spots between discrete sensors
• Meter-level pinpointing: event localization within 0.5 m to enable targeted maintenance
• Hazardous area safety: intrinsically safe; armored fiber transmits light only and is immune to high-voltage EMI
• Rugged, flexible armored sensing cable with LSZH sheath rated for -40 to +120 °C
• No field power required along the cable: entirely passive glass fiber
• SCADA & AI integration: 10.4-inch industrial touchscreen, Modbus RTU (RS485), RJ45 Ethernet, and 16 programmable relay outputs

Operating Principle - Raman OTDR
Raman Optical Time Domain Reflectometry (OTDR) derives temperature profiles and event locations by comparing Anti-Stokes and Stokes backscatter intensities.

• Stokes band: intensity influenced by fiber transmission characteristics and laser power
• Anti-Stokes band: intensity strongly temperature-dependent

Technology Comparison - DTS vs Point Sensors

• Coverage: VTI-GL-100C (DTS) — 100% continuous line; Point sensors — only at installed points
• Blind spots: DTS — none; Point sensors — gaps between sensors
• Field power: DTS — 0 W (passive glass); Point sensors — require wiring or batteries
• EMI immunity: DTS — immune; Point sensors — susceptible to EMI

Critical Applications

• High-voltage cable tunnels & trays — detect overheating, insulation breakdown and fire hazards with meter-level accuracy
• Long-distance pipelines — detect leaks, flow anomalies, blockages and abnormal temperature variations across tens of kilometers
• Oil storage & LPG tanks — continuous monitoring around shells, bases and floating roofs with integration for automated fire suppression
• Road & utility tunnels — mounted along ceilings and corridors for rapid fire detection and ventilation control support
• Conveyor belts & bulk handling — continuous surveillance to detect bearing friction and prevent spontaneous ignition
• Integrated operations — centralized AI monitoring with GIS mapping, trend analysis and dynamic line ratings

Technical specifications

• Commercial designation: VTI-GL-100C
• Controller: 4 optical channels (FC/APC)
• Maximum distance per channel: 5 km; total 20 km continuous monitoring
• Spatial resolution: 0.5 m
• Temperature accuracy: ±1 °C; temperature resolution 0.1 °C
• Measurement range: -40 to +120 °C (cable-dependent up to +300 °C)
• Sampling frequency: 3 samples/s/channel
• Relay outputs: 16 programmable relays (250 VAC / 3 A)
• Communications: 1×RJ45 Ethernet, 1×RS485 (Modbus RTU), 1×RS232
• Display & local HMI: 10.4-inch industrial touchscreen
• Power & dimensions: DC 24V, 50W; dimensions 420 × 182 × 580 mm; operating temperature -10 to +50 °C
• Armored sensing cable: optical core 62.5 μm / cladding 125 μm; multi-mode / single-mode options
• Cable outer diameter: Ø3.0 mm with stainless-steel spiral & braided armor
• Sheath: flame-retardant LSZH, anti-static, UV-resistant
• Tensile & crush resistance: installation tension ≤500 N, operating ≤300 N; crush resistance ≤5000 N/10 cm
• Minimum bending radius: ≥60 mm (dynamic), ≥30 mm (static)