DHS40 Series Heat Spy High Performance Handheld Infrared Pyrometers

The DHS40 is available in ten different spectral ranges. Please review the Order Guide and provide your desired spectral range when requesting a quote.

This model replaces the DHSA24, DHSA26, DHSA28, DHS29X, and DHS35XT Series units.


The DHS40 High Performance Heat Spy Handheld Infrared Pyrometers are an updated and expanded line of our classic high performance Heat Spy line.  This industrial infrared temperature sensor series features an accuracy of up to 0.25% of of reading and 1°C / 1°F resolution.  Available in 10 different spectral ranges and temperature ranges, the DHS40 Handheld Infrared Pyrometer has the most options of any manufacturer.

The DHS40 series is available for use in Molten Metal (1M), Non-Ferrous Metals (2M), and Low Temperature Processes (LT) models. This is the only hand held portable infrared on the market for use with models for Cold Metal (3M), Combustion Through Flame (MT), Burning Gas (F4), Glass > 1 mm thick (G5), Glass < 1 mm thick (G7), Polyethylene Film (P3), and Polyester Films (P7).

The case is made of cast and extruded aluminum for lightweight and rugged durability, as well as additional shielding against EMF interference originating from machinery and engines.

Both photodiode and thermopile sensors are used, depending on the spectral range and applications of each model.

DHS40 Series models and applications

Model CodeTypeSpectral RangeTemperature SpanApplication
1MFerrous Metal1.0μm1112° to 5432°F (600° to 3000°C)Hot Graphite
2MHot Metal & Hot Ceramic1.6μm752° to 4172°F (400° to 2300°C)Hot Metals and Hot Ceramics
3MCold Ferrous Metal2.4μm302° to 2192°F (150° to 1200°C)Iron, Steel, and Steel Alloy
MTThru Flame3.9μm1112° to 2732°F (600° to 1500°C)Through hot furnace gases and clean
burning gas flames, indicates correct
temperatures of substances during warm
up process in industrial furnaces
F4Burning Gas4.11 - 4.72μm752° to 2912°F (400° to 1600˚C)CO2 Gas (4.24 Micron) in Chimney
NO2 Gas (4.55 Micron) in Combustion
Hot CO Gas (4.66 Micron) in Combustion
Flame Temperature in Boiler / Furnace
Utility Power Station
Biomass Boilers
Garbage Incinerators
Hazardous Waste
G5Thick Glass5.0μm752° to 4082°F (400° to 2250°C)Glass above 1 mm thickness
Flat Glass Production
Glass Bending
Automobile Glass Assembly
G7Thin Glass7.9μm104° to 1832°F (40° to 1000°C)Thin Glass Below 1 mm thickness
Light Bulb Production
Medical Vial Production
P3Thin Film Plastics3.43μm212 °to 932°F (100° to 500°C)Plastic Thin Film (1 to 3 mm), Polyethylene
Films and all types of fluorocarbon-plastics
Polyethylene (PE)
Polypropylene (PP)
Polyamide (Nylon)
Polystyrene (PS)
Polyvinyl Chloride (PVC)
Vinyl / Acrylic / Polycarbonate
P7Thin Film Plastics7.9μm104° to 1112°F (40° to 600°C)Plastic Thin Film, (1 to 3 mm) Polyester
Films and all types of fluorocarbon-plastics
Cellulose Acetate
Teflon (Fluoroplastic FEP)
Polyvinyl Chloride (PVC)
Acrylic / Polycarbonate
Polyamide (Nylon)
Polyester (>10 μm)
LTLow Temperature8 to 14μm-40° to 1472°F (-40° to 800˚C)Organic Materials
Baking Production
Painted Metal Surfaces
Rubber, Tires
Thicker Plastics

The DHS40 comes in a attache style foam lined, locking carrying case.  Case is watertight, dust proof, and features an auto air purge.  Case dimensions: 18.1 inches x 12.9 inches x 4 inches.


Sensor Specifications: Ambient Temperature

0° to 50°C (32° to 122°F)

Sensor Specifications: Storage

-20° to 70°C (-4° to 158°F)

Sensor Specifications: Relative Humidity

10% to 95% non-condensing

Housing Material

Cast and Extruded Aluminum

Housing Dimensions

13 inches x 6 inches x 15.5 inches
330.2 mm x 152.4 mm x 393.7mm


2.2 lbs (0.99 kg)


128 x 64 dot


4 Key: Menu, Up, Down, and Enter


High or Low

Signal Processing

Max, Min, Average, Delta T


9V Alkaline Battery

Battery Life

Approximately 30 hours


± 0.25% of reading or ± 1°C
± 0.6% of reading or ± 1°C
depending on model


± 0.10% of reading
± 0.30% of reading
depending on model

LCD Resolution

1°F / 1°C

Response Time

5 mS, 150 mS, or 750 mS,
depending on model

Adjustable Emissivity

Adjustable between 0.10 and 1.00

Trigger Lock


LCD Backlight


Laser Sighting

Available on models 1M, 2M, 3M, MT, G5, P7, G7. and LT

Storage Temperature

-4° to 158°F (-20° to 70°C)