High-performance fibre optic pyrometer


  • Temperature ranges from 100°C to 2,000°C
  • Miniature fibre optic sensing head for ambient temperatures up to 150°C
  • Choice of precision optics and through-lens LED aiming light
  • Extremely fast 1 ms response time
  • Short measurement wavelength for improved performance on reflective metal surfaces, compared with general-purpose models
  • 4-20 mA, voltage, alarm outputs
  • RS-232 communications
  • Optional display and configuration unit

The FibreCube provides fast and precise temperature measurements in demanding applications.

Measurements as low as 100°C are possible, with a response time of just 1 ms. The sensing head contains no electronics, and may be used in ambient temperatures of up to 150°C with no need for cooling.

Very small objects can be measured. A measurement spot as small as 0.4 mm is available with standard optics, and even smaller with special optics (contact Calex).

For measuring small targets at long distances, the FibreCube is the most capable of any Calex sensor, with measured spot sizes as small as 6 mm at 1 metre distance.

A built-in bright green LED aiming light illuminates the exact size and location of the measured spot, so the sensor is easy to aim with total precision.

The fibre optic cable is made to order, with lengths of up to 10 m or 28 m available depending on the model. The length can be specified to the nearest metre.

All models can measure through glass or quartz viewport windows.

Measurement Specifications

Temperature Range
FC-TL 100°C to 1500°C
FC-TM 180°C to 2000°C
FC-TH 240°C to 2000°C

FC-PL 220 to 1650°C
FC-PM 300 to 2000°C
FC-PH 400 to 2000°C

FC-AL 500 to 2000°C
FC-AM 600 to 2000°C
FC-AH 700 to 2000°C
Aiming light
Green LED, through-lens (shows size and location of measurement area)
Accuracy of Measurement
Measurements below 800°C: ±4°C
800°C to 1200°C: ±0.5% of reading
1000°C to 2000°C: ±1.0% of reading
±2°C ±0.2% of reading
Measurement Resolution
Measurements within 50°C of minimum of measurement temperature range: 3°C
Measurements within 50°C of minimum of measurement temperature range: 1°C
Otherwise: 0.5°C
Response Time (95%)
Analogue output: 0.001 to 5 s
Adjustable via averaging function
Warm up time
1 minute
1 analogue output
1 alarm output
Digital RS-232 communications
Analogue Output Type
4-20 mA (this is the default factory setting on all models)

Output type can be changed via optional PM030 touch screen interface or RS-232 to a choice of:
0-20 mA
0-1 V DC (other voltage ranges available, contact Calex)
Analogue Output Scale
Full temperature range depending on model
Adjustable via optional touch screen module or RS232
Digital Communications
RS232C Modbus RTU, non-isolated
Output swing width: ±4 V approx.
Baud rate: 4800, 9600, 19200, 38400, 57600, 115200 bps (selectable)
Measured Spot Diameter
From 0.4 mm depending on measurement distance and choice of optics (see Field of View Diagrams below)
Alarm output
1 open drain alarm output, rated 27 V DC, 0.2 A
Alarm hysteresis
Adjustable, 0°C to 99.9°C
Peak hold function
0.01 to 10 s, time or discharge mode, configurable
Emissivity Setting
Adjustable, 0.3 to 1.0 (default setting 0.95) in 0.001 increments
Emissivity may be set as low as 0.05 with reduced accuracy
Supply Voltage
24 V DC
(allowable range: 4.7 to 27 V DC)
0.1 A max
Output Cable Connection to Sensor
Connector built into sensor

PM030 Specifications

Touch Screen Display Format
2.83” (72 mm) resistive touch TFT, 320 x 240 pixels, backlit
Configurable Parameters
Language (English, Chinese, Japanese)
Temperature units °C/°F
Displayed temperature
LED sighting on/off
Date & time (for data logging time stamps)
Peak hold period, decay level
Averaging period
Correction (gain/offset)
Emissivity setting (with teach function)
Reflected energy compensation (with teach function)
Output type
Output temperature range
Polarity on error
Alarm mode, levels, hysteresis

PM030 Data Logging Specifications

MicroSD Card (optional), max. 32 GB, equal to 16 years of data at the fastest sample rate of 1 per second
Data Logging Interval
1 second to 1 day (configurable)
Internal Clock Battery
1 x BR 1225 3V (not included)
Variables Logged
Instantaneous target temperature, hold temperature, alarm events
File format
Configurable Parameters (Data Logging)
Sample period
Number of samples
Scheduled start
Configurable Parameters (Alarm Logging)
Log times when triggered, acknowledged, reset
Log data while triggered

Field of View Diagrams (click to expand)

Each optics option is available for one FibreCube temperature range only (M, L, or H). For example: for FC-AM sensors, choose from the “M” optics. Note: Smaller measured spot sizes are available. If these options are not suitable, contact Calex to discuss special optics. The given measured spot size contains 90% of the energy detected by the sensor. We normally recommend the target is at least twice as large as the given measured spot for maximum accuracy. Accuracy specifications are valid up to the maximum distances shown.

Mechanical Specifications

Sensor body with 1 m fibre optic cable: 155 g
2 m output cable: 160 g

Environmental Specifications (PyroCube Sensor)

Operating Ambient Temperature
0°C to 150°C (sensing head and fibre optic cable)
0°C to 50°C (electronics module)
Storage Temperature
-15°C to 70°C
Operating Ambient Humidity
30% to 85% RH non-condensing

Display Options

Model PM030 Optional touch screen terminal for indication, configuration, data logging and alarm outputs. Sensor is available with or without display.



Application Examples

Welding preheat
Instantly and accurately measure the preheat temperature of steel surfaces before they are welded.
Finishing and coating
Measure the preheat temperature of bare metal surfaces on small parts before they are coated.
Tools and machine shafts
Small, bare metal machine parts such as cutting tools, bearings and shafts can be monitored without contact.

The FibreCube may be installed with or without the PM030 touch screen interface.

Electrical Installation

Connections (with optional PM030 display/interface unit)

Connections (sensor only)

Dimensions (mm)

PM030 Touch Screen Interface

Provides temperature display, alarm outputs, sensor configuration and data logging for one FibreCube sensor. The PM030 is optional – configuration parameters are stored in the FibreCube sensor, and the sensor can be connected directly to instrumentation.

Panel Mounting Kit

Provides an easy way for the PM030 touch screen interface module to be fixed to a panel.

Mounting Brackets

The stainless steel adjustable mounting bracket offers a rigid support for the sensing head and allows 2-axis rotational adjustment.

Protective Window

The protective calcium fluoride window helps prevent contamination and damage of the FibreCube sensor’s lens.


Air Purge Collar

Helps keep dust, moisture and contaminants away from the lens. Use clean (instrument) air.

Airless Dust Protector

Helps keep dust away from the lens. No air supply is required.

Extension Cable

5 metre long cable for FibreCube sensor, fitted with connectors at both ends.

Right Angled Mirror

Reflects the FibreCube sensor’s field of view by 90 degrees, making it easier to install in tight spaces. Includes a protective calcium fluoride window to keep dust from settling on the mirror and lens.

PID Controllers

The analogue output of the FibreCube is compatible with our 4-digit indicating controllers for closed-loop PID control.

The FibreCube sensor may be ordered with or without the PM030 touch screen interface.

Ordering Information