PyroMini 2.2
Two-part Pyrometer for High Temperature Targets and Metals


  • Temperature ranges from 100°C to 2000°C
  • Short wavelength measurement for better accuracy on reflective targets such as many metals
  • 4-20 mA or RS485 Modbus outputs
  • Miniature sensing head and configurable electronics module
  • Touch screen interface (optional)
  • Data logging to MicroSD Card (optional)

General Specifications

Temperature Range
PT models: 100°C to 400°C
MT models: 250°C to 1000°C
HT models: 450°C to 2000°C
Max. Temperature Span (-CRT models)
Full temperature range (up to 1550°C)
Min. Temperature Span (-CRT models)
4-20 mA or RS485 Modbus (Up to 247 sensors may be installed on a single Modbus network)
Field of View
Choice of wide-angle or focussed optics (see Field of View Diagrams below)
± 2°C or 1% of reading, whichever is greater
± 0.5°C or 0.5% of reading, whichever is greater
Emissivity Setting
Adjustable, 0.10 to 1.00
Emissivity Setting Method
-CB models: via two rotary switches in electronics module
-BB and -BRT models: via RS485 Modbus
-CRT and -BRT models: via touch screen
Response Time, t90
≥240 ms (90% response)
Spectral Range
2.0 to 2.6 μm
Supply Voltage
24 V DC ± 5%
Maximum Current Draw
100 mA
Max. Loop Impedance (-CB and -CRT models)
900 Ω (4-20 mA output)
Alarm Relays (-CRT and -BRT models)
2 x Single Pole Changeover alarm relays, rated 24 V DC, 1 A, isolated 500 V DC

Data Logging Specifications

Data Logging Interval
1 to 86,400 seconds (1 day)
MicroSD Card
Max. capacity: 32 GB (not included)
Internal Clock Battery
1 x BR 1225 3V (not included)
Variables Logged
Target temperature, sensing head temperature, electronics module temperature, max, min, average, emissivity setting, reflected energy compensation Temperature, alarm events
File format
Configurable Parameters
Sample period, number of samples, scheduled start date and time

Touch Screen Interface Specifications

Touch Screen Display Format
2.83” (72 mm) resistive touch TFT, 320 x 240 pixels, backlit
Configurable Parameters
Temperature range, temperature units, emissivity setting, reflected energy compensation, alarms, signal processing, Modbus address (-BRT models), date and time, data logging
Temperature Units
°C or °F configurable
Temperature Resolution
Alarm Configuration
Two alarms with adjustable level, individually configurable as HI or LO. Alarm 2 can be set to target temperature or sensing head internal temperature
Signal Processing
Average, peak hold, valley hold, minimum, maximum

Field of View Diagrams

Please note: The given measured spot diameter contains 90% of the energy detected by the sensor. For maximum accuracy, we normally recommend the target is at least twice as large as the given measured spot. The sensor may be used at longer distances than shown above. In clean air there is no maximum measurement distance, and the distance does not affect the sensor's measurement accuracy; this is because the PyroMini 2.2 detects only the wavelengths of IR that are not absorbed by the atmosphere.

Mechanical Specifications

Construction (Sensing Head)
Stainless Steel 316
Construction (Electronics Module)
Die Cast Aluminium
Major Dimensions (Sensing Head)
18(dia.) x 45(l) mm (see Installation)
Major Dimensions (Electronics Module)
98(w) x 64(h) x 36(d) mm
Mounting (Sensing Head)
M16 x 1 mm thread
Mounting (Electronics Module)
Requires two M4 screws for wall mounting (see Installation)
Cable Length (sensing head to electronics module)
1 m (standard), up to 30 m (optional)
Weight with 1 m cable
390 g (approx)
Cable Connections
Removable screw terminal blocks (see "Connections")
Conductor size: 28 AWG to 18 AWG
Output Cable Gland
Suitable for cable diameters 3.0 to 6.5 mm

Environmental Specifications

Sensing Head Electronics Module (without touch screen) Electronics Module (with touch screen)
Environmental Rating IP65 (NEMA 4) IP65 (NEMA 4)
Ambient Temperature Range 0°C to 70°C 0°C to 60°C 0°C to 60°C
Relative Humidity Maximum 95% non-condensing Maximum 95% non-condensing Maximum 95% non-condensing
CE Marked Yes Yes Yes
RoHS Compliant Yes Yes Yes

Electromagnetic Compatibility Standards

The PyroMini 2.2 series conforms to EMC Directive EN61326-1:2006 (Electrical equipment for measurement, control and laboratory use – Industrial) as well as industrial standards for electromagnetic immunity and emissions.

The PyroMini 2.2 combines the unique interface and output features of the PyroMini with a short-wavelength spectral response. It is ideal for demanding industrial applications where the target temperature is very high, or where the target surface has a low emissivity, for example many types of metal. For example, applications include the following:

Typical Applications

Steel industry
Short-wavelength 2.2 μm sensors are better-suited to measuring steel surface temperature than general-purpose 8 to 14 μm models. Contact Calex for advice on measurement locations on annealing lines, furnaces, rolling mills and railway rail manufacturing.
Food Industry
Hot stainless steel surfaces above 100°C can be measured quickly and accurately with the PyroMini 2.2. Applications include burner control in conveyor ovens and dryers.
Dryer cylinder surface temperatures exceeding 100°C (such as in linerboard manufacturing) may be measured directly with the PyroMini 2.2. See also the PyroUSB 2.2 for temperatures below 100°C (in the manufacture of finer paper types).

Electrical Installation

Dimensions (mm)

PM180 6-Channel Hub

6-channel touch screen hub for temperature display, alarms, configuration and data logging, compatible with PyroMini Modbus models, PyroMiniBus and PyroBus sensors. Isolated RS485 Modbus master and slave interfaces allow multiple hubs to be connected to a larger network. Optional modules provide analogue and relay outputs.

Panel Mounting Kit

The Panel Mounting Kit (PMK) is an ABS plastic assembly that allows the wall-mounted touch screen display to be fitted to a panel.

The bezel measures 128 x 84 mm, and the required panel cut-out is 111 x 65 mm. The PMK is compatible with panels up to 5 mm thick.

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.

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.

Protective Plastic Window

When fitted over the lens of the sensor, the protective plastic window in stainless steel holder provides mechanical protection and helps retain fragments of lens in case of damage. Adjust the sensor’s emissivity setting to compensate for the presence of the window for maximum accuracy. This accessory is ideal for the food and pharmaceutical industries.

PID Controllers and Indicators

The 4-20 mA output of PyroMini 2.2 -CB and -CRT models may be connected to any of our indicating controllers for PID control.

The PyroMini is a two-piece sensor with a miniature sensing head and separate electronics module. Each model number includes both parts.

Ordering Information