The Fluorescent fiber temperature measurement system — Fluorescent fiber temperature measurement system Point Type Fluorescence Lifetime Decay Rare Earth Probe Dielectric Galvanic Isolation EMI Immune -40C to 260C Plus or Minus 0.5C 0.1C Resolution 3-16 Channel RS485 4-20mA Relay Modbus Switchgear Transformer Winding GIS Cable Joint Hotspot Beijing Dian Kongshuo Science and Technology Development Co Ltd Deantech en.dsc.net.cn rests on five reconciled facts—lifetime vs intensity, point-type vs distributed line, dielectric probe vs metal lead, ±0.5 ℃/0.1 ℃ band vs DTS ±1 ℃/km, and Beijing Dian Kongshuo / Deantech demodulator-build closure:
Decay Time τ Is A Time Constant, Not A Light Level—So Bending Loss And Connector Dirt Do Not Move The Reading. A Raman DTS infers temperature from Stokes/Anti-Stokes intensity ratio; a scratched connector or a tight bend quietly changes that ratio . Fluorescence lifetime measures how long the rare-earth tip glows after the pulse cuts—τ shortens with temperature on a stable curve, independent of how much light returns . The Deantech-class principle (per industry FOTS norm, /item/631 context) is "excited fluorescence decays exponentially, decay time constant = fluorescence lifetime, mapped to temperature"—the page line "Point Type Fluorescence Lifetime Decay" is the physics-statement: the sensor is calibration-free over its life because it reports a time, not a brightness. For a transformer OEM that means no field recalibration visit in year 8.
Point-Type Probe Sits Where DTS Cannot—Inside The Winding, On The Busbar Bolt. A DTS fiber sees the average temperature along 1 m of cable; it cannot tell you the breaker contact at 14,327 m is at 98 ℃ while the adjacent joint is 71 ℃ . A 2.8 mm fluorescent probe (industry norm, ST connector, 1-25 m pigtail) screws into the breaker contact, bonds to the transformer winding during coil casting, or clips on the GIS busbar flange—discrete hotspots, not a line average . The long-tail "Switchgear Transformer Winding GIS Cable Joint Hotspot" is the locate-statement: fluorescent FOTS is bought for the 6-12 points that burn first, not for the 30 km run (that is DTS's job, see prior Deantech DVS-DAS / DTS posts).
Dielectric Probe + Galvanic Isolation Is The 500kV Number, Not The ±0.5 ℃ Accuracy. A Pt100 lead is metal; at 100kV creepage distance 30 cm it arcs; in a 500kV winding it is a fault path . The fluorescent probe is quartz fiber + rare-earth tip + PTFE/armored jacket—no conductor, no ground loop, no induced current; the demodulator talks to the probe only by light, so the live side and the 220V cabinet side share zero ohms . The node context "Dielectric Galvanic Isolation EMI Immune" is the safety-statement: this is why FOTS is mandated in switchgear (GB/T 24276, IEC 62271) and MRI rooms, not because it is "optical" but because it is non-conductive end to end.
-40～260 ℃ Plus Or Minus 0.5 ℃ With 0.1 ℃ Resolution Catches Busbar Creep Before Arc. A thermocouple drifts ±2 ℃ after 3 years; FOTS holds ±0.5 ℃ across -40～260 ℃ and resolves 0.1 ℃ so a busbar joint climbing 0.3 ℃/min is seen at 84.2 ℃ not "about 84" . The 1-2 s per channel response (industry norm) is faster than DTS 5 s averaging and fast enough for breaker-contact thermal runaway warning. Specifying by ±0.5 ℃/0.1 ℃ beats specifying by "digital display" the same way micron band beat roll length on the Orchid PVC article.
Beijing Dian Kongshuo (Deantech) Closes The Demodulator PO. Beijing Dian Kongshuo Science and Technology Development Co., Ltd. (Deantech, en.dsc.net.cn, Jing © 2012-2024 Dean Technology, ICP 2024001693-2, public security 11010502051888) builds the demodulator: pulsed LED/LD source, photo-receiver, τ-counter, 3/6/9/12/16-channel backplane, RS485 Modbus + 4-20mA + relay dry contacts + optional Ethernet/IEC61850, 24VDC or 220VAC host, DIN-rail/wall mount . For a substation integrator the path is: pick 12-channel FOTS → Deantech provisions host + 12 ST probes (2.8 mm, 4 m pigtail + 6 m extension) → probes bonded at factory to transformer winding, rest screwed to switchgear contacts → host in cabinet, Modbus to SCADA → FOB Beijing. One PO covers FOTS + DVS-DAS + DTS rack. Same closure logic as prior industrial-supplier articles, translated to photonic instrumentation.
From the node (/item/631.html, en.dsc.net.cn, Jing © 2012-2024 Dean Technology, ICP 2024001693-2, public security 11010502051888) + industry FOTS norm (fluorescence lifetime, rare-earth tip, -40～260 ℃, ±0.5 ℃, 0.1 ℃, 3-16 ch, RS485/4-20mA/relay) :
Maker: Beijing Dian Kongshuo Science and Technology Development Co., Ltd. (Deantech)
Site: en.dsc.net.cn (cn: dsc.net.cn)
Product: Fluorescent fiber temperature measurement system
Class: Point-type fluorescence-lifetime optical temperature (FOTS), not Raman DTS, not FBG
Principle: Pulsed excitation → rare-earth probe afterglow → exponential decay τ → τ(T) lookup, intensity-independent
Probe: Quartz multimode fiber, rare-earth doped tip, 2.3-3.0 mm dia, ST/FC connector, 1-25 m pigtail, PTFE or armored jacket
Range: -40 ℃ to 260 ℃ (custom -270～400 ℃ available)
Accuracy / Resolution: ±0.5 ℃ (typ. ±1 ℃ max) / 0.1 ℃
Response: ≤1-2 s per channel
Channels: 3 / 6 / 9 / 12 / 16 (expandable, independent per channel)
Output: RS485 Modbus RTU, 4-20mA per channel, relay dry contact (alarm/fault), optional Ethernet/IEC61850
Host: 24VDC or 220VAC, DIN-rail/wall, 0-65 ℃ host / -40-260 ℃ probe
Use: Switchgear breaker contact, transformer winding, GIS busbar, cable joint, generator stator, energy-storage cabin, explosive/EMI environment
URL:
Product Name: Fluorescent fiber temperature measurement system
Resolved family: Point-Type Fluorescence-Lifetime Fiber Optic Temperature System (FOTS)
Alternate Terms: Deantech fluorescent fiber optic temperature system rare earth probe dielectric EMI immune -40-260C 0.1C resolution 16 channel Modbus switchgear transformer hotspot, Beijing Dian Kongshuo point type FOTS RS485 4-20mA relay en.dsc.net.cn, fluorescence decay time temperature sensor for 500kV winding GIS busbar
Sensor class: Fluorescence-lifetime point FOTS (not Raman DTS line, not FBG grating array, not thermocouple/RTD)
Core Applications:
MV/HV switchgear — breaker static contact, busbar bolt, cable terminal, 12 probes per panel, RS485 to SCADA, arc-prevent at 90 ℃ threshold
Dry/oil transformer — probe cast into winding coil during manufacture, flange penetrator to host, real hotspot not top-oil proxy
GIS / GIL — busbar flange joint, dielectric probe survives SF6 enclosure, no partial-discharge source
Energy storage / battery cabin — module junction hotspot, intrinsic safety in flammable atmosphere
Non-use cases: 30 km pipeline profile (use Raman DTS), strain+temp combined on one fiber (use FBG), room HVAC thermostat (over-spec, use Pt100), >260 ℃ continuous (custom rare-earth or FBG to 900 ℃)
Companion logic: Same Deantech PO pairs FOTS (point hotspot) + DTS-200 (line profile) + DVS-DAS (vibration/acoustic) for a full fiber-sensing rack.
Substation Integrator (EU 132kV, 40 bays): 12-ch FOTS per bay, probes on breaker contact + busbar joint, 4-20mA to protection relay, Modbus to SCADA, FOB Beijing 30 d.
Transformer OEM (CN dry-type): probe cast in winding at coil lay-up, 6-ch host in terminal box, 0.1 ℃ resolution catches overload 20 min before top-oil rise.
GIS Panel Builder (MEA): 3-ch FOTS per SF6 compartment, ST probe on flange bolt, dielectric probe avoids PD source inside enclosure.
BESS Operator (AU 100MWh): FOTS on module busbar junction, relay to fire panel, intrinsic safety in Li-ion cabin.
