Digi-Stem® DST611 & DST651 Series RTD Thermometers with Dual Sensor and Output

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.  The Digi-Stem® DST611 model digital thermometer offers all the benefits of our DST600 series digital thermometer, with the addition of a second, four wire RTD with an internal euro style terminal block, wired for 2, 3, or 4 wire capability. The primary RTD is powered by the battery, and acts as the reference thermometer / TiD for the entire system. The second RTD is powered by customer provided 24VDC loop power for complete separation; use the secondary RTD for output to a recorder or control panel. Access the secondary sensor via connected external Turck® brand 4 pin connector on the side of the case for a watertight connection.

The Wahl Digi-Stem® DST611 Digital Thermometers is designed for critical applications, with low acid canned food processing in mind. A reliable and secure option, the DST611 series features self-checking technology to continuously verify the accuracy of its electronics and indicate any out-of-tolerance condition by displaying "Err" on the screen.  The unique Probe ID feature prevents the connection of unauthorized probes to the meter.

The DST611 series uses high precision, high reliability components to meet the requirements of FDA Final Rule 21 CFR Part 113 for replacing traditional Mercury-in-Glass thermometers.

Pt100, Class A 4 wire platinum RTD sensors in MgO packed MI cable with a wide temperature range and high accuracy design for applications that require accurate and reliable temperature monitoring are used. Choose from rigid, remote, or adjustable angle RTD probes built to order to customer specification and sold separately.  The DST610 Series utilizes programmable “RØ” for “matching” the sensor to meter.

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.  Optional panel mount is also available.

Polycarbonate H frame is standard; choose the DST651 with laser welded stainless steel H-Frame for additional protection against RF interference and moisture intrusion.

The primary RTD is powered by 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 statement on Calibrating Digi-Stem® Systems for use as Food Processing TID's


Isolated Secondary Sensor

Connect via Internal Terminal Block and external Turck 4 pin connector on side of case for a watertight connection.

Selectable Resolution

User selectable 1° / 0.1° resolution on "R" models

Panel Mount

Panel Mount option available on "P" models

Battery Power

Standard Model: 1 - C size, Lithium Thionyl Chloride, 3.6V, International model: 1 - AA size, Lithium Thionyl Chloride, 3.6V

Temperature Range

-50°F to 500°F (-45.5°C to 260°C)

Meter Accuracy

± 0.1°F/C, over 1-year period (@ Tamb = 23°C ± 5°C)

Meter & Probe Accuracy

Temperature ≤ 300°F (148.8°C) = ± 0.3°F (± 0.2°C)
Temperature > 300°F (148.8°C) = ± 0.25% of reading


1.0” 4-digit LCD display with icons for °F, °C, and low battery. Readable up to 30 feet.

Display Resolution

Standard display resolution: 0.1°F/°C. Select "R" model for user selectable resolution 1.0° or 0.1°F/°C.

Sample/Display Rate

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

Ambient Operating Temperature

-40° to 158°F (-40° to 70°C)


10 to 100% RH, non-condensing

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

Maximum of 0.003°/°C over Ambient Operating Temperature Range from 23°C ± 5°C

Probe Type / Sensor

Pt100 Class A 4-wire platinum RTD sensors in MgO packed MI Cable. R0 = 100Ω, Alpha = .00385 Ω/Ω/°C with Serial ID Chip.

H Frame Material

DST600: Polycarbonate, DST640: Stainless Steel


°F and °C, switchable


MIL STD 202G method 201A extended to 60Hz vibration: 10 to 60 Hz

Battery Life

C Size Battery: >2 years nominal at 2 second update interval. Up to 10 years if set on 10 second update rate., AA Battery: 1 year nominal at 3 second update interval.


DST600: Stainless Steel Enclosure with Polycarbonate H Frame and window, NEMA 4X rated.
DST640: All Stainless Steel Enclosure and laser welded Stainless Steel H Frame with Polycarbonate Window, 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)


Two year warranty covers defects in materials and workmanship.