Real-time thermal surveillance on circuit breaker contacts, tulip fingers and arcing chambers — 24/7, EMI-immune, ±1°C accuracy. Detect contact wear and hotspots before they cause arc flash or forced outage.
Circuit breaker contacts degrade silently. Each fault-clearing operation causes micro-welding, pitting and spring fatigue on tulip fingers — incrementally increasing contact resistance and generating heat that conventional inspection never catches between maintenance cycles.
INNO's fluorescent fiber optic probes are the only sensor technology that can be placed directly on high-voltage circuit breaker contacts without galvanic connection, battery power, or any electronics at the measurement point — making them immune to the intense electromagnetic fields generated when a breaker clears a fault current.
A 2.5 mm all-glass probe is mounted directly on the breaker contact or terminal during a scheduled maintenance outage. No electronics at the tip.
The transmitter sends a blue LED pulse down the optical fiber to excite the rare-earth crystal at the probe tip.
The crystal fluoresces; the decay time constant is a direct, absolute function of temperature — no drift, zero calibration required over 25+ years.
Temperature is computed to ±1°C and delivered via Modbus RTU, 4–20 mA, or IEC 61850 — with relay alarm contacts for local protection integration.
Based on thousands of VCB, GCB, and ACB deployments worldwide, these six measurement points deliver the highest fault-detection coverage per probe. Each installation is performed during a scheduled racking-out or maintenance outage — no panel redesign required.
Loose connection or poor contact may cause overheating at the upper terminal.
Poor contact or oxidation of the static contact finger may cause abnormal heating.
Wear, oxidation or foreign particles on the moving contact may cause overheating.
Arcing during opening or closing may cause high temperature at the contact area.
Loose connection or poor contact may cause overheating at the lower terminal.
Poor contact at the outgoing cable connection may lead to local overheating.
INNO probes are geometry-independent and have been factory-validated on all major circuit breaker architectures — from compact MV vacuum units to large HV SF6 dead-tank breakers.
The most common MV switchgear breaker. Probes monitor tulip contact temperature and vacuum interrupter surface — providing early detection of contact wear and vacuum degradation before dielectric failure occurs.
High-voltage GCB contacts operate inside sealed SF6 chambers. Fiber optic probes rated to 140 kV are installed through existing bushing ports, providing continuous contact temperature data without compromising gas integrity.
Large LV and MV air-insulated circuit breakers in industrial and commercial switchboards. Probes mount on main contact arms, arc chutes and cable terminations — monitoring the full thermal profile under high continuous current.
High-density LV distribution boards where thermal imaging is impractical. Miniature fiber optic probes installed at busbar tap-offs and cable terminations provide continuous hotspot coverage across entire LV distribution switchboards.
From single-bay monitoring to complete switchroom coverage — choose by channel count or go turnkey with our integrated online monitoring system.
Most popular model for single MV VCB panels — covers all three-phase tulip contacts plus neutral or interrupter surface in one unit.
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Ideal for dual-bay circuit breaker clusters or breakers with both line-side and load-side contact monitoring across all three phases.
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Full coverage of a three-phase circuit breaker: line-side contacts, load-side contacts and cable terminations — all from a single transmitter.
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Compact model for monitoring a single contact zone across three phases — cost-effective entry point for VCB contact or cable lug monitoring.
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Complete hardware + software solution — probes, multi-channel transmitters, communication modules and web-based dashboard for fleet-wide breaker health monitoring.
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Panel-mount local readout for substations without SCADA — shows real-time temperature for each monitored contact point on a clear backlit display.
View Product →Send us your breaker drawings, type plate or photos — our engineers will recommend the right channel count and probe geometry at no cost.
INNO switchgear probes are manufactured and calibrated entirely in-house at our Fuzhou facility. All probes are HV-insulation tested before shipment. Custom ranges, bend-radius-optimized fibers, and high-temperature variants available on request.
| Temperature Range | -40°C to +260°C (high-temp version to +300°C) |
| Measurement Accuracy | ±1°C (±0.5°C high-accuracy version available) |
| Resolution | 0.1°C |
| Response Time | <1 second |
| Probe HV Insulation | 140 kV withstand voltage |
| Probe Diameter | 2.5 mm (custom geometries available) |
| Fiber Length | 0–20 m standard (customizable) |
| Channel Options | 3 / 4 / 6 / 9 / 16 / up to 64 per transmitter |
| Communication | RS485 Modbus RTU / 4-20 mA / IEC 61850 |
| Alarm Output | Relay contacts — configurable absolute / differential / rate-of-rise |
| Power Supply | AC/DC 220 V |
| Sensor Lifetime | 25+ years, calibration-free |
| Certifications | CE · RoHS · ISO 9001 · ISO 14001 · ISO 45001 |
| Compatible Breaker Types | VCB · GCB (SF6) · ACB · OCB — all MV/HV classes |
INNO fiber optic systems cover every critical monitoring dimension of modern switchgear — from thermal hotspots to arc flash detection and gas leakage.
Real-time monitoring of circuit breaker contact temperature, mechanical wear and thermal anomalies in operating components. Early fault warning reduces arc flash risk and extends equipment service life.
Precisely detect thermal hotspots at busbar joints, cable terminations and contact points before faults develop. Enable proactive preventive maintenance and eliminate unplanned outages caused by thermal defects.
Continuously track busbar temperature distribution and insulation degradation trends. Ensure reliable power transmission across main and sectional busbars with IEC 61850 / Modbus RTU SCADA integration.
Real-time arc flash detection and precise fault location for millisecond-speed protective response. Effectively prevent arc flash incidents from causing severe damage to equipment and personnel.
Comprehensive temperature measurement across all critical switchgear assets for early detection of overheating and proactive maintenance. Fiber optic sensors rated to 140 kV — fully suited for high-voltage environments.
Real-time tracking of SF6 gas leakage and concentration in gas-insulated switchgear. Ensure safe GIS operation and environmental compliance while reducing the risk of insulation failure.
Continuous acquisition and analysis of partial discharge activity. Early identification of insulation defects through high-sensitivity sensors to reduce unplanned switchgear failures and unscheduled downtime.
A unified platform integrating temperature, partial discharge, arc flash, SF6 gas and mechanical condition monitoring into one dashboard. Multi-bay, multi-device visibility across an entire substation from a single system — with full SCADA / IEC 61850 connectivity.
Still have questions? Our engineers respond within 4 hours.
Share your circuit breaker type and we'll recommend the right probe configuration — no commitment required.
Share your breaker drawing, type plate or panel photo and get a custom fiber optic probe placement plan, bill of materials and quote within one business day — completely free, no commitment.
