Overview

The Electrical Fire Monitoring System continuously tracks and statistically analyzes the primary causes of electrical fires — including conductor temperature, current, voltage, and leakage current. It detects safety hazards in electrical circuits and equipment in real time (such as abnormal cable temperature, short circuits, overloads, overvoltage, undervoltage, and leakage), effectively preventing electrical fires.

GB 50016-2006 Code for Fire Protection Design of Buildings and GB 50045-1995 Code for Fire Protection Design of High-Rise Civil Buildings both specify that "non-fire electrical loads in certain buildings or locations should be equipped with an electrical fire monitoring system." Shandong Province further mandated in Government Order No. 263 (2013) Regulations on Fire Safety Management of High Fire-Risk Units in Shandong Province that "high fire-risk units shall install a residual current fire alarm system," with detailed implementation rules provided in DB 37/T 2122—2012.

Problem with Traditional Solutions

Traditional electrical fire monitoring systems are built independently from existing low-voltage motor protection and distribution protection systems, using additional residual current transformers or temperature sensors with separate detectors. In practice — especially in drawer-type switchgear — this approach presents several issues:

• Protection devices in motor and distribution circuits already have residual current and temperature detection. Adding a separate fire alarm residual current transformer creates installation problems: placing it inside the drawer cabinet risks open-circuit faults via secondary plug connections; mounting it on the cable outlet side is unreliable.
• Electrical fire monitoring detectors (one-to-many) have no suitable installation location and may occupy an entire modular drawer slot.
• Redundant investment in both fire monitoring detectors and leakage transformers.

Wanlong Integrated Solution

Based on the above challenges, Suzhou Wanlong Electric Group developed an Integrated Solution for Low-Voltage Motor Protection, Distribution Protection, and Electrical Fire Monitoring, combining the fire monitoring detector with motor circuit and distribution circuit protection devices into a single unit.

Advantages over Traditional Solutions

• Eliminates redundant investment in fire monitoring detectors and leakage transformers
• Optimized design — compact, reliable installation with fewer failure points
• Unified HMI for easy operation
• Optimized communication channels, reducing overall investment

Solution Components

(1) Low-Voltage Motor Circuit Integrated Solution — ST520F + ST570

• Audible and visual alarm: ≥70 dB within 1 meter
• Alarm signal relay output: 3 channels, AC220V, resistive 10A
• Three residual current inputs: 50–1000 mA (typically 300 mA)
• Communication: RS485, Modbus protocol
• Dual certified: CCC and CCCF

(2) Low-Voltage Distribution Circuit Integrated Solution — ST420F

• Multi-function meter: accuracy Class 0.5
• Feeder protection with zero-sequence overcurrent protection
• Residual current electrical fire monitoring detector function

(3) Electrical Fire Monitoring Device — ST2000FB

• Supports up to 512 electrical fire monitoring detectors
• Supports 2 DI and 8 DO channels
• Uplink communication: 1× Ethernet port + 1× RS-485 port