PyroUSB 2.2 (Superseded by PyroUSB [New Version])
PC Configurable Pyrometer for Metals and High Temperature Targets
Alternative Product:PyroUSB

Sensor Features

  • Temperature ranges from 45°C to 2000°C
  • Short-wavelength spectral response for better accuracy on reflective targets
  • Can measure through glass
  • Rescalable 0-20 or 4-20 mA output
  • Fully configurable
  • USB interface (cable and Windows software included)
  • Use the USB or analogue output only, or both together

Software Features

  • Sensor configuration
  • Display of measured temperature
  • Scrolling temperature chart
  • On-screen and audible alarms
  • Data acquisition to Excel-compatible file

Key Feature Tags

Read more

General Specifications

Temperature Range
LT: 45°C* to 300°C
PT: 100°C to 400°C
MT: 250°C to 1000°C
HT: 450°C to 2000°C
15:1 (with LT or PT temperature range)
25:1 (with MT or HT temperature range)
75:1 (with MT or HT temperature range)
ø7.5mm @ 500mm (with MT or HT temperature range)
Selectable 4 to 20 mA or 0 to 20 mA (linear with temperature)
Via PC port conforming to USB 2.0
±1% of reading or ±2°C, whichever is greater
±0.5% of reading or ±0.5°C, whichever is greater
0.1 to 1.0
Response Time, t90
≥240 ms (90% response)
Spectral Range
2.0 to 2.6 μm
Supply Voltage
24 V DC (26 V DC max)
Sensor Voltage
11 V DC min
Max Loop Impedance
900 Ω @ 24 V DC
Maximum Span (analogue output)
Full temperature range (up to 1550°C)
Minimum Span (analogue output)

Software Specifications (CalexSoft)

Operating System
Windows XP or newer
Temperature display, scrolling temperature chart, sensor configuration, data acquisition with scheduled start, on-screen and audible alarms, OPC Server interface
Data log file format
.csd (comma separated text format, may be imported to spreadsheet software such as Excel)

Environmental Specifications

Environmental Rating
Ambient Temperature Range
0ºC to 70ºC (cooling option available for use in higher ambient temperatures)
Relative Humidity
95% max. non-condensing

Field of View Diagrams

Please note: 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. Sensors may be used at longer distances than the above diagrams show. There is no maximum measurement distance in clean air; this is because Calex sensors detect only the wavelengths of infrared radiation that are not absorbed by the atmosphere.

Mechanical Specifications

Stainless Steel
25 mm diameter x 106.5 mm long
Thread Mounting
M20 x 1 mm pitch
Weight with Output Cable
175 g
Output Cable Length
1 m (longer cable available to order)
USB Cable Length
1 m

Minimum Measurable Temperature (PU151LT2.2 only)

Graph showing the minimum measurable object temperature (Tmin), determined by surface emissivity (ε) and sensor temperature (Ts). Applies to model PU151LT2.2 only.

PU151LT2-2 Minimum Measurable Temperature

Electromagnetic Compatibility Standards

Conforms to  EN61326-1, EN61326-2-3 (Electrical Equipment for Measurement, Control and Laboratory Use – EMC Requirements – Industrial)

The unique low-temperature, short-wavelength capability of the PyroUSB 2.2 means it can provide accurate readings on shiny metals at much lower temperatures than other sensors allow. For example, some typical uses include:

Typical Applications

The short-wavelength PyroUSB 2.2 provides a more accurate reading on reflective metal surfaces, such as iron and steel, than longer-wavelength sensors. Applications include general steel strip temperature measurements at low temperatures, steel temperature measurement before the reheat furnace and temperature at the coiler on the hot rolling mill
Extrusion, Forging and Casting
The PyroUSB 2.2 is ideal for measuring the temperature of steel dies and workpieces in extrusion, forging and casting applications
Measure the temperature of hot food products inside glass containers from 45°C to 300°C using the PyroUSB 2.2. The pyrometer measures through the glass; readings can be taken on-line without interrupting production.

Other applications include tunnel pasteuriser temperature monitoring, and temperature of bare stainless steel surfaces on food manufacturing machinery, such as hot rollers and conveyors
Brake testing
Non-contact measurement of ceramic, carbon, iron and steel brake disc temperatures between 45°C and 2000°C on brake test rigs
Wind power
Brake disc surface temperature monitoring in wind turbines, to help warn of overheating and optimise cooling cycles
Bearings, gearboxes and shafts
Non-contact temperature measurement of bare steel surfaces: the PyroUSB 2.2 is less susceptible than long-wavelength sensors to errors caused by reflections
Furnaces and ovens
The high-temperature capability of the PyroUSB 2.2 is ideal for measuring the temperature of hot objects inside furnaces and ovens, including steel mill heat treatment furnaces.
Pipe coating
Furnace-heated or induction heated pipe temperature measurement, at the preheat stage, before coating
Paper, Print and Converting
Monitoring of the surface temperature of hot bare steel rollers, such as steam-heated dryer cylinder temperature in paper manufacturing. The temperature reading may be used for control and alarm

The 4-20 mA analogue output and USB output may be used individually, or both may be used at the same time.

Electrical Installation

Dimensions (mm)

Air Purge Collar

The air purge collar is used to keep dust, fumes, moisture and other contaminants away from the lens. Air flows into the fitting on the side and out of the aperture at the front.

Fixed Mounting Bracket

The L-shaped fixed mounting bracket offers a rigid support for the sensor and allows fine rotational adjustment about one axis.

Adjustable Mounting Bracket

The adjustable mounting bracket consists of a fixed mounting bracket plus another L-shaped bracket. When assembled as shown, the adjustable mounting bracket offers a rigid support for the sensor and allows fine two-axis adjustment.

Air/Water Cooled Housing

The air/water cooled housing allows the sensor to withstand ambient temperatures above the normal 70°C limit. Depending on the degree of cooling required, air or water may be used as the cooling fluid. To prevent condensation forming on the lens, an air purge collar is included with this item. The air/water cooled housing must be ordered with the sensor and cannot be fitted by the user.

Laser Sighting Tool

The Laser Sighting Tool screws onto the front of the sensor during installation and shows precisely where the sensor is aiming. Once the sensor has been aimed at the centre of the target and locked in position, the Laser Sighting Tool can be removed. The laser is operated via a latching push button on the front of the tool.

Dual Laser Sighting Bracket

The Dual Laser Sighting Bracket is a sturdy mount for the sensor and provides continuous target sighting while measurements are being taken. Two parallel lasers indicate the centre of the measured spot and are controlled by a remote switch on the electronics module.

PID Controllers and Indicators

The 0-20 or 4-20 mA output of the PyroUSB 2.2 may be connected to any of our indicating controllers, which provide temperature display, PID control and alarm relay outputs.

This product range has been upgraded. See PyroUSB (New Version)