Digi-Stem® DST400 Thermocouple Thermometer

Digi-Stem Meters & Probes are sold separately and paired together to create a complete custom system. This listing is for the meter only.

Please review our Order Guide and choose the meter power source, mounting, and other specifications needed to build a meter.


Digi-Stem® meters and probes are sold separately for a completely customizable system. Our popular Wahl Digi-Stem® Digital Thermometers are ideal for use in a wide variety of processes.  The DST400 Series is our thermocouple model, available for use with type K, J, T, E, and S thermocouples.  Select any of the 5 factory programmed Thermocouple inputs at time of purchase, and change to any of the other 4 inputs after purchase with our easy to use optional DSTCAL software. Interchangeable stickers are provided to indicate which thermocouple type is programmed at any given time.

Our Digi-Stems® are known for their reliability and rugged cases.  The housing is stainless steel with a NEMA-4X rating.  Dimensions are 5.3 inches wide x 4.3 inches high x 2.7 inches deep (13.5cm wide x 10.9 high x 6.9 cm deep).  The large 1 inch high LCD display is readable from 30 feet away.

Choose from rigid, remote, or adjustable angle thermocouple probes built to order to customer specification and sold separately.  The DST400 is also compatible with third party thermocouple probes with a 1/2 inch NPT fitting.

Polycarbonate H frame is standard; choose optional stainless steel for additional protection against RF interference and moisture intrusion.

Standard models are powered by and shipped with one C size, Lithium Thionyl Chloride, 3.6V battery.  Due to shipping restrictions, meters with this battery must be shipped by ground transport.  For international or air shipping, choose the "I" option, configured for and powered by one AA size, Lithium Thionyl Chloride, 3.6V battery, or the "NB" option for the meter only with no battery included:  purchase the required battery from a supplier near your location.

Read our DST400 Application Story.

The DST400K replaces obsolete models DST200 and DST300.


Thermocouple Types

K, J, T, E, S

H Frame Material

DST400: Polycarbonate, DST440: Stainless Steel

Temperature Ranges

Type K: -40° to 2500°F (-40° to 1371°C)
Type J: -40° to 2192°F (-40° to 1200°C)
Type T: -40° to 752°F (-40° to 400°C)
Type E: -40° to 1832°F (-40° to 1000°C)
Type S: 32° to 3200°F (0° to 1760°C)


°F and °C, switchable

Meter Accuracy

Type K: < 1000 = ± 0.5°F, ± 0.3°C. > 1000 = ± 2°F, ± 1°C
Type J: < 1000 = ± 0.5°F, ± 0.3°C. > 1000 = ± 2°F, ± 1°C
Type T: ± 0.5°F, ± 0.3°C
Type E: < 1000 = ± 0.5°F, ± 0.3°C. > 1000 = ± 2°F, ± 1°C
Type S: Full Range = ± 2°F, ± 1°C


1.0” 4-digit LCD display with icons for °F, °C, and low battery.

Display Resolution

< 1000 = 0.1°; > 1000 = 1°

Sample/Display Rate

2 Seconds, adjustable in .25 Second intervals to .25 to 10 seconds with software


10 to 100% RH, non-condensing

Ambient Operating Temperature

-40° to 158°F (-40° to 70°C)

Ambient Temperature Coefficient (From 23°C ± 5°C)

Input: < 200°C, Maximum of: ± 0.02°C/°C
Input: > 200°C, Maximum of: ± 0.05°C/°C

Sensor Lead Resistance

1000 ohms maximum

Battery Power

Standard Model: 1 - C size, Lithium Thionyl Chloride, 3.6V, International model: 1 - AA size, Lithium Thionyl Chloride, 3.6V, No Battery Model: No Battery Included with unit for easy international shipping. Requires purchase of 1 - C size, Lithium Thionyl Chloride, 3.6V battery from local supplier.

Battery Life

C Size Battery: > 4 Years at 2-second sample rate, 1 to >10 years (approximate) when set to .25 to 10 second sample/display rate
AA Size Battery: 2 Years at 4-second sample rate, 0.5 to > 3 years (approximate) when set to .25 to 10 second sample display/rate


Stainless Steel, NEMA 4X rated


5.3 in. W x 4.3 in. H x 2.7 in. D (13.5 cm W x 10.9 H x 6.9 cm D)


2 lbs (1 kg)

Don't forget to add…