Electrical Contact Wireless Temperature Monitoring Device

1. Product Overview

The Electrical Contact Wireless Temperature Monitoring Device is designed for real-time monitoring of temperature rise at electrical contact points such as circuit breaker contacts in switchgear and busbar joints. It effectively prevents accidents caused by overheating due to poor contact at breaker contacts or busbar joints in air-insulated high-voltage switchgear. Employing 433 MHz short-range wireless communication technology, it enables online temperature monitoring and over-temperature alarm of electrical contacts without compromising the insulation level of the switchgear.

2. Key Selling Points

· Passive Inductive Power Harvesting, Zero Maintenance: Sensors are powered by current induction from the primary conductor, requiring no batteries. This eliminates battery replacement, leakage, and expiration concerns, ensuring long-term operation after a single installation.

· Fully Wireless Transmission, No Insulation Modification: 433 MHz wireless communication with no electrical connection between sensors and the main control unit. Does not reduce switchgear insulation level or alter the primary circuit.

· Large Capacity: Up to 27 Measurement Points: A single main control unit supports up to 27 temperature points, covering all critical heating contacts within one switchgear panel, reducing the number of host units and deployment cost.

· 10-Second Fast Sampling: Temperature data refreshes every 10 seconds, capturing sudden temperature rises in time and avoiding missed alarms due to slow sampling.

· High Accuracy: ±1°C: Measurement accuracy of ±1°C within the 0°C to 120°C range, enabling precise detection of latent heating defects.

· Level 4 EMC Immunity: The main controller passes Level 4 ESD and EFT/B immunity tests per GB/T 17626.2 and GB/T 17626.4, suitable for the strong electromagnetic environment inside switchgear.

3. Product Features

· Adopts advanced digital and wireless transmission technology, providing complete spatial isolation from live parts without altering the insulation performance of the equipment under test; safe and reliable in operation;

· Temperature measurement range up to 0~125 °C;

· Temperature sensors powered by inductive energy harvesting;

· Temperature sensors use passive inductive energy harvesting, operating normally within a starting current range of >5 A;

· Sensor housings made of high-temperature resistant, flame-retardant material.

4. System Architecture & Working Principle

4.1 System Architecture

The system adopts a three-layer architecture consisting of the perception layer, aggregation layer, and platform layer:

· Perception Layer: Passive wireless temperature sensors, installed via clip-on or strap mounting on live contacts, with inductive power harvesting and wireless transmission.

· Aggregation Layer: Main control unit installed in the switchgear instrument compartment, receiving data via 433 MHz, with local display and alarm functions.

· Platform Layer: Backend monitoring software (optional), centrally managing data from multiple switchgear panels, supporting trends, reports, and remote alarms.

4.2 Working Principle

The sensor harvests energy from the high-voltage conductor using the principle of electromagnetic induction. When current flows through the measured conductor (>5 A), the power harvesting coil generates an induced electromotive force, which is rectified and regulated to power the internal circuitry. This drives temperature acquisition and wireless data transmission at 433 MHz. The main control unit receives, displays, and evaluates the data, triggering alarms when necessary—achieving a fully isolated temperature measurement solution with "power harvesting on live parts, wireless transmission, and low-voltage-side reception."

5. Applications

5.1 Typical Monitoring Points

· Circuit breaker moving/fixed contacts and contact arms

· Busbar connection points and busbar lap joints

· Cable terminations and cable inlet ends

· Disconnector contacts

· Transformer bushing connections

· Reactor and capacitor connections

5.2 Compatible Switchgear Types

· 3~35 kV metal-clad withdrawable switchgear (e.g., KYN28)

· Ring main units (RMU) and withdrawable switchgear

· 0.4 kV low-voltage fixed/drawer switchgear

· GIS gas-insulated switchgear (optional)

5.3 Industry Scenarios

· Power plants, substations, and switching stations

· Industrial enterprise distribution rooms (metallurgy, chemical, manufacturing)

· Data centers and IDC facilities

· Commercial complexes and office building distribution

· Rail transit power supply systems

· Renewable energy stations (photovoltaic, energy storage)

6. Functional Highlights

· Over-temperature alarm: Instant alarm when temperature exceeds threshold, with local audible and visual indication.

· 24/7 online monitoring: Continuous data acquisition, eliminating blind spots in manual inspection.

· Easy installation: Sensors are directly clipped or strapped onto contacts, requiring no wiring; suitable for both new and existing switchgear.

· High-temperature flame-retardant housing: Sensor enclosure made of high-temperature resistant, flame-retardant material for harsh in-cabinet environments.

· Open communication: Supports standard protocols for uplink, integrable with existing monitoring platforms/SCADA systems.

7. Customer Value

· From Reactive Repair to Proactive Prevention: Real-time temperature trend monitoring enables early detection of latent faults such as poor contact.

· Reduced O&M Cost: Passive and maintenance-free; no periodic battery replacement, reducing power outage maintenance frequency.

· Improved Power Supply Reliability: Prevents short circuits, fires, and other accidents caused by overheating, reducing unplanned outages.

· Support for Condition-Based Maintenance: Accumulated temperature history data provides a basis for equipment condition assessment and life management.

8. Technical Specifications