Fiber Optic Distributed Temperature Sensing System

DTSX200 is an integrated optical fiber sensing system designed to provide the most accurate distributed temperature measurements over long distances while reducing operating costs and increasing production.

Built on Yokogawa’s PLC & SCADA process control platforms, DTSX200 is the only distributed temperature sensing system to also offer programmable logic capabilities. It features an intelligent, modular design that monitors changes in the temperature and notifies the operator of problems early on.


Easy to Integrate in Process Control System
Yokogawa is the only supplier that can provide an integrated automation solution with DTSX200, DCS, SCADA, Field Instruments and outdoor housing.

Wide Temperature Range
Primarily used for temperature sensing, the compact hardware platform offers a wide range of temperature measurements up to 6km. The DTSX200 can be used in all regions world-wide with an Operating Temperature of -40 °C to +65 °C.

Compact and Low Power Consumption
Because of its low power consumption capability, DTSX200 can be installed in remote areas running on solar power.

Modular Design
The DTSX200 modular design allows interchangeable configurations up to 16 fiber optic channels, control I/O module and various power supply options.


The DTSX200 is designed for Oil & Gas conventional and unconventional in-well applications, LNG and Refinery facilities, leak detection, and other thermal monitoring applications.

  • Conveyor Belt Fire Detection
  • Duct Fire Detection
  • Power Cable Monitoring for Overheating
  • Bus Bar Monitoring for Overheating
  • Leak Detection
  • Furnace Monitoring for Safety and CBM
  • Maximizing variable speed drive efficiency


DTS Technology

All light interacts with matter! For example, imagine standing in a pitch black garage with no external light source. Inside this garage is a bright red sports car. Needless to say, you cannot see the sports car or the color of the sports car itself. However, when you turn on the lights to the garage, you can immediately see the light source reflecting the bright red color off the car. The light that is bouncing off the red sports car is only bouncing off the "red" spectrum, therefore, your eyes see the sports car as, well, red.

Distributed Temperature Sensing Fiber Optic Cable

This DTS fiber optic phenomenon is also true when you shoot a pulse of light (laser pulse) off of a molecule, in this case, the fiberglass molecule in the optical fiber cable. When the light source enters the optical fiber cable, most of the light bounces (backscatter) back unchanged (no change in wavelength). However, a small amount of that light shifted/changed. That shift/change from the light source is called Raman Scatter. Since Raman Scatter is thermally influenced by temperature, the intensity depends on temperature. Distributed temperature sensing is capturing the shift/change from the propagating light pulse and measuring the intensities between the two signal components (stokes and anti-stokes).

DTS Optic  Distributed Temperature Sensing

The Raman signal is the signal used for evaluation of temperature. It is sufficiently strong and has a unique temperature dependence. Its wavelength is also shifted substantially (about 40/Nm) from the main Rayleigh peak, thereby allowing the dominant Rayleigh and Brillouin peaks to be filtered out.

The Raman signal is comprised of the so-called “Stokes” and “anti-Stokes” bands. The Stokes band at the higher wavelengths (redshifted) is stable with little temperature sensitivity. The anti-Stokes band at the lower wavelengths (blue shifted) exhibits a temperature sensitivity, where the higher the energy within the band, the higher the temperature and vice versa. A ratio of the energy or area within the Anti-Stokes band to that of the Stokes band can be simply related to the temperature of the fiber optic line at the depth where the signal originated.




Items Specifications

Distributed temperature measurements

Distance Measurement distance range 1 km, 2 km, 3 km, 4 km, 6 km
Sampling resolution 10 cm, 20 cm, 50 cm, 1 m
Spatial resolution 1 m (10 to 90%)
Temperature Measurement temperature range -200 to +800°C
Temperature resolution Range
Time 1 km 3 km 6 km
10sec 0.5 1.1 4.2°C
1min 0.3 0.6 2.1
10min 0.1 0.2 0.7
(1sigma, without optical switch)
Sensor optical fiber Optical fiber 50/125 μm GI
(No reflection at end of optical fiber)
Optical connector E2000/APC
Interface Serial
  3 ports, non-isolated, RJ45 modular jacks
Full duplex, asychronous
SERIAL 1 Function: Communication (Modbus)
Baud Rate: 1.2, 2.4, 4.8, 9.6, 19.2, 38.4, 57.6
115.2 kbps
SERIAL 2 Function:,Communication (Modbus)
Baud Rate: 1.2, 2.4, 4.8, 9.6, 19.2, 38.4
SERIAL 3 Function: Maintenance (Private)
Ethernet Interface LAN 1 port, 10BASE-T or 10BASE-TX,
RJ45 modular jacks, automatic negotiation,
automatic MDI, with Network power switch
Power Supply Consumption Operating Mode 10 W
Power save mode 2.1 W
Dimensions (W x H x D) 197.8 x 132.0 x 162.2 mm (6 slots width)
Weight  2.5 kg

Temperature calibration of the Sensor Optical Fiber for DTSX200 is required before temperature distribution measurement.


Item Specifications
Insertion loss 0.6 dB (Typical)
1.4 dB (Max.)
1.0 dB (Typical)
3.0 dB (Max.)
0.8 db (Typical)
1.4 dB (Max.)
Distributed temperature measurements Measurement Single end, Double end
Sensor optical fibers Optical fiber 50/125 μm GI closed end, non refraction required
Optical connector E2000/APC
Optical channels 2 channels 4 channels 16 channels
Interface Control Controlled by DTSX200
Display LEDs: HRDY, RDY, Alarm, Active channel
Power supply Consumption 1 W 1 W Operating 4.5 W
Power save 1 W
Dimensions (W x H x D) 65.8 x 130.0 x 160.3 mm
(2 slots width)
65.8 x 130.0 x 160.3 mm
(2 slots width)
65.8 x 130.0 x 160.3 mm
(2 slots width)
Weight 0.6 kg 0.64 kg  

Note:  As a guideline, the module should be replaced periodically every 4.7, 6, and 9.5 years for continuous operation of 15-second, 20-second and 30-second measurements, respectively.

Compliant Standards

Item Specifications
(✓: Compliant)
Suffix Code
0: Standard 9: EAC
Safety Standards CSA C22.2 No. 61010-1-04  
EN 61010-1:2010  
EN 61010-2:2010  
CU TR 004  
EMC Standards CE Marking EN 55011: 2009 +A1:2010 Class A Group 1
EN 61000-6-2:2005
EN 61000-3-2:2006 +A1:2009 + A2:2009
EN 61000-3-3:2008
RCM EN 55011:2009 +A1:2010 Class A Group 1  
KC Marking Korea Electromagnetic Conformity Standard  
EAC Marking CU TR 020  
Laser Safety Class IEC 60825-1/2007, EN 60825-1 Class 1M
FDA (CDRH) 21CFR Part 1040.10
Standards for
Hazardous Location
Class I, Division 2, Groups A, B, C, D T4
FM 3600-2011
FM 3611-2004
FM 3810-2005
Type "n"
II 3 G Ex nA ic [op is] II C T4 Gc X
EN 60079-0:2009, 2012
EN 60079-11:2012
EN 60079-15:2010
EN 60079-28:2007
Class I, Division 2, Groups A, B, C, D T4
C22.2 No. 0-10
CAN/CSA-C22.2 No. 0.4-04
C22.2 No. 213-M1987

Note: Under EU legislation, the manufacturer and the authorized representative in EEA (European Economic Area) are indicated below: Manufacturer: YOKOGAWA Electric Corporation (2-9-32 Nakacho, Musashino-shi, Tokyo 180-8750, Japan). Authorised representative in EEA: Yokogawa Europe B.V. (Euroweg 2, 3825 HD Amersfoort, The Netherlands).

List of Modules and Modules Descriptions

Type Model Function Explosion Protection
Type "n" NI
DTSX200 Distributed Temperature Sensor DTSX200 Distributed temperature sensor
Power supply module NFPW426 Power supply module
(10 to 30 V DC input)
NFPW441 Power supply module
(100 to 120 V AC input)
NFPW442 Power supply module
(220 to 240 V AC input)
- - -
NFPW444 Power supply module
(21.6 to 31.2 V DC input)
Base module for DTSX200 DTSBM10 Base module for DTSX200
Optical switch module DTOS2 Optical switch module (2ch)
DTOS4 Optical switch module (4ch)
DTOS16 Optical switch module (16ch)
CPU module NFCP050 CPU module  レ
Rack mount kit DTRK10 Rack mount for optical fiber N.A. N.A. N.A.
Optical fiber for DTSX DTFB10 Optical fiber for DTSX N.A. N.A. N.A.

レ: conforming
-: Not conforming yet
N.A.: Not applicable
For the details of the power supply modules and the CPU module, see GS 34P02Q13-01E and GS 34P02Q12-01E.

DTSX200 Module Base (Required)

DTSX200 Module BaseThe base module for DTSX200 is used for mounting various function modules including the DTSX200 distributed temperature sensor, power supply modules, optical switch modules and CPU I/O modules.

Optical Switch Module (Optional)

image_958.jpgInstalling an optical switch module (2, 4 or 16-channel model) allows monitoring of multiple optical fibers using a single DTSX200 system.

  • DTOS2: 2 channel Optical Switch Module
  • DTOS4: 4 channel Optical Switch Module
  • DTOS16: 16 channel Optical Switch Module

Power Supply Module (Required)

  • NFPW426: 10 to 30 VDC
  • NFPW441: 100 to 120 VAC
  • NFPW442: 220 to 240 VAC
  • NFPW444: 21.6 to 31.2 VDC

CPU I/O Module (Optional)

Installation of a CPU I/O module allows for additional control capability on the DTSX200.

  • NFCP050: 12 AI, 2 AO, 16 DI, 8 DO, 2 PI, 1 AI for battery monitoring


Model DTSX200 DTSX200Distributed Temperature Sensor
Suffix Codes -N Standard type
0 Standard type
9 EAC mark
E E2000/APC
N Basic type
G With ISA Standard G3 option

DTSX200 Module Base

Model DTSBM10 Base module for DTSX200
Suffix Codes -N Standard type
0 Standard type
9 EAC mark
N Basic type
G With ISA Standard G3 option

Optical Switch Module

Model DTOS2 Optical Switch module 2ch
DTOS4 Optical Switch module 4ch
DTOS16 Optical Switch module 16ch
-N Standard type
0 Standard type
9 EAC mark
E E2000/APC
N Basic type
G With ISA Standard G3 option

Power Supply Module

Model Reference (Input voltage range)
NFPW426 10 to 30 VDC
NFPW441 100 to 120 VAC
NFPW442 220 to 240 VAC
NFPW444 21.6 to 31.2 VDC

The development of unconventional resources, such as heavy oil, oil sands and shale gas has been progressing in line with the increase in global energy demand. DTSX200 can measure the temperature distribution along an optical fiber with a length of several kilometers are being applied to extraction of unconventional resources. DTSX200 maximizes oil/gas extraction by providing real time continuous temperature measurement through different injection dynamics. In addition to well optimization, DTSX200 provides critical data that help monitor and detect wellbore conditions for leaks, water penetration and gas breakthrough. DTSX200 also provides control capability (measurement of flow, pressure, temperature, valve position, etc.) on top of fiber optic temperature measurement. More importantly, compared to conventional wellbore monitoring technology, DTSX200 is more robust, cost effective and accurate.

Features Benefits
Ultra low power consumption: 10W Perfect for solar application in remote areas
Operating temperature range: -40 dec C to 65 dec C Perfect for rugged environment without cooling or heating
Fiber optic cable sensor Provides a complete and continuous profile of the downhole well
Control capability with NFCP050 module Monitor and control external devices such as flow, pressure, valve position, temperature, ect.
Wide range of communication protocols Connect to existing DCS, PLC, DAQ and wireless interface
6km optical fiber = 6,000 points! Cost effective way of measuring temperature compared to traditional sensor technology



              DTSX200 Oil & Gas 2

Yokogawa DTSX200 can protect the infrastructure of existing power line/cable and reduce cost by monitoring the thermal dynamics of the power transmission and distribution line. By measuring the temperature of the power line, power grid operators can maximize the usable capacity of the power current by avoiding power cable damage and extending the cable life by maintaining optical power current. More importantly, operators can identify hot spots, fire breakout and location of fire along the entire grid. DTSX200 minimizes the potential power grid network outages and streamlines preventative maintenance process. Because of its immunity to electromagnetic interference, DTSX200 is ideal for high voltage, high noise environment. DTSX200 is designed to deploy in the following environments:

  • Underground power cables
  • Subsea power cables
  • Overhead power lines
  • Distribution station
  • Substations
Features Benefits
Isolation from electromagnetic interference Fiber optic is isolated from electrical magnetic current
Real time temperature measurement and monitoring Measure and monitor real time power grid/cable temperature
Measure and monitor multiple power circuits/cables Up to 16 channels of optical switch can be connected
Report and data analysis Access historical data using HTTP, SFTP or web browser
Wide range of communication protocols Connect to existing DCS, PLC, DAQ and wireless interface
6km optical fiber = 6,000 points! Cost effective way of measuring temperature compared to traditional sensor technology

DTSX200 Pipeline 1DTSX200 Pipeline 2

Yokogawa DTSX200 offers superior pipeline leak detection by using fiber optic solutions that provide a complete temperature profile along the entire length of a pipeline. When a leak occurs anywhere along the pipeline, a localized temperature change is produced at that specific location. The optical fiber cable, due to its close proximity to the pipeline, has adequate thermal contact and can provide accurate temperature readings. By comparing every new temperature profile scan acquired against a reference profile taken under normal conditions, it is possible to detect temperature anomalies which may indicate a possible pipeline failure or external extrusion which might result in or be an actual break. DTSX200 is designed to deploy in the following applications:

  • Gas pipelines: Ammonia, natural gas, carbon dioxide
  • Liquid pipelines: Crude oil, heated oil, gasoline, PNG, LNG, brine, steam

A leak induced temperature change can be either from a localized cooling or heating. For leaks occurring in pipelines carrying crude oil and other similar products, it is expected that a localized warming will result from a leak as it is often a common practice to transport the crude at a warm temperature to reduce its viscosity.

Leaks in pressurized gas pipelines or those carrying LNG or other cryogenic products, a localized cooling effect will be observed as a result of the Joule Thompson effect, whereby a rapidly expanding gas under pressure lowers the surrounding temperature.

Pipeline Leak Source



Gas Expands, Temperature Decreases



Features Benefits
1m special resolution Identify the exact location of the leak/failure
Up to 0.1°C temperature resolution Possible leak detection within the first 1 minute of occurrence *
Fiber optic cable sensor Real time, accurate and continuous detection of gas, oil and fuel pipeline leaks
Report and data analysis Access historical data using HTTP, SFTP or web browser
Wide range of communication protocols Connect to existing DCS, PLC, DAQ and wireless interface
6km optical fiber = 6,000 points! Cost effective way of measuring temperature compared to traditional sensor technology

*Assuming appropriate scan rate and data refresh intervals are used

DTS Optic  Distributed Temperature SensingEarly fire detection to critical process and environment is an important component to any safety system. A blazing fire has devastating consequences to important assets, products and most importantly, human lives. Furthermore, the cost of downtime due to fire leads to lost opportunities and costly repairs. Discrete sensor technology often fails due to the surrounding environment conditions such as dust, humidity, heat and corrosion. In addition, it is expensive to maintain a conventional sensor technology due to constant repair. Yokogawa's DTSX200 is designed to detect fire in critical assets under the most extreme conditions and offers unmatched reliability, performance and cost savings.

Yokogawa's DTSX200 is designed to deploy in the following fire detection applications:

  • Conveyor belts carrying important goods
  • Tank farms
  • Cable trays
  • Underground tunnels
  • Pipelines (underground, above ground)
  • Nuclear facilities
  • Mining, Refinery
Features Benefits
1m special resolution Identify the exact location of the fire
Up to 0.1°C temperature resolution Possible fire detection within the first 10 seconds of occurrence *
Fiber optic cable sensor Unlike discrete sensor or IR camera, fiber optic cable eliminates "blind spots"
Coated fiber optic cable Immune to dust, humidity, corrosion and dirt
Report and data analysis Access historical data using HTTP, SFTP or web browser
Wide range of communication protocols Connect to existing DCS, PLC, DAQ and wireless interface
6km optical fiber = 6,000 points! Cost effective way of measuring temperature compared to traditional sensor technology

* Assuming appropriate scan rate and data refresh intervals are used

DTFB10 Optical Fiber Test Box

DTFB10 Optical FiberThe optical fiber for DTSX is used for checking the operation of both DTSX200 and DTSX3000 units.

DTRK10 Rack Mount Kit (Optical Fiber Tray)

DTRK10 Rack Mount kitThe rack mount kit can be used for laying optical fibers in a cabinet.

DTAP3000 Control Visualization Software

The DTSX3000Control Visualization Software (DTAP3000) is used to control the DTSX3000 and visualize DTS data on a PC. In addition, the software displays measurement data graphs and generate LAS format. DTAP3000 allows a user to perform control, monitoring and analysis from anywhere on Ethernet network.

DTS Optic  Distributed Temperature Sensing

DTS Optic  Distributed Temperature Sensing

DTAP3000D Data Conversion Software

The Data Conversion Software option (DTAP3000D) allows the DTSX3000 to generate data files in WITSML format. When the DTSX3000 is configured for WITSML conversion using DTAP3000D, then the DTSX3000 will generate data files in WITSML format.



Reducing waste in the separator and electrode drying furnaces with Yokogawa’s distributed temperature sensors ensure comprehensive monitoring of thermal events in real-time.


A belt conveyor fire detection solution employing the DTSX distributed optical fiber temperature sensor can greatly reduce crises that can threaten a company's survival.

Application Note

Temperature Monitoring Solution for 
Quick Detection of Fires in Fume Ducts


With industrial and economic development comes increasingly large and advanced power plants and factories. Nevertheless, we find many cases where the original cables, cable tunnels, and other components of the power infrastructure have languished under continuous operation.


Hot Spot Monitoring for Safety with a Fiber Optical Temperature Sensor

Application Note

Temperature Monitoring Solution for Maximum VSD Operating Efficiency


Recently, several ARC Advisory Group analysts and management team members had a chance to sit down with the new Yokogawa President and COO, Mr. Takashi Nishijima, and several other top Yokogawa executives to discuss the company's burgeoning presence in the worldwide upstream and midstream oil & gas industry.

Yokogawa Technical Report

The development of difficult to recover unconventional energy resources, is progressing. Figure 1 shows an example of how unconventional heavy oil is extracted from tar sand by reducing its viscosity with steam. To ensure efficient mining, changes in the underground temperature distribution will need to be monitored.


Hans Meulman, Toru Fukuzawa and Dwight Eldredge, Yokogawa, Corporation of America, explain the operation and application of DTS for leak detection in pipelines.




DTSX has been increasingly used in a variety of applications such as fire detection, leak detection and preventative maintenance.


In this webinar you will learn how temperature detection with DTS avoids loss of revenue. Leakage, accidents or malfunction means loss in production and thus loss of revenue. By detecting a fire or a system malfunction before major environmental damage occurs, the operator can significantly lower the risk profile to major environmental incidents. With DTS you can reduce risks and increase safety.

After the webinar, attendees will leave with a basic understanding of DTS technology and where and how they can use DTS for their temperature solutions in different applications.

Key Learning Objectives:

  • Understand the applications and benefits of Distributed Temperature Sensor as alternative against tradition temperature measurement
  • Learn how you get a better temperature profile
  • DTS technology as proven way for temperature measurement

Yokogawa address misconceptions on how Distributed Temperature Sensing (DTSX) works and what industries use them.

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