Fluke Calibration 9103/9140 Field Dry-Well
Key features
- Accuracy to ±0.25°C and comes with an RS-232 interface.
 - The 9103 covers below-ambient temperatures as low as –25 °C. The 9103 is stable to ±0.02 °C
 - The 9140 has a temperature range of 35 °C to 350 °C. The 9140 has a stability of ±0.05 °C.
 - Features designed with user convenience and productivity in mind.
 
Product overview: Fluke Calibration 9103/9140 Field Dry-Well
Portable, fast, and accurate temperature sources for on-site calibration
Exceptional Performance in a Compact Design
The Fluke 9103 and 9140 Field Dry-Wells outperform the competition in nearly every category—performance, size, weight, ease of use, calibration simplicity, software integration, and price.
Each unit features:
- Adjustable heating and cooling rates via the front panel
 - Thermal switch actuation testing
 - Multiple-hole inserts for compatibility with a wide range of probe sizes
 
Fast Calibration with Minimal Downtime
- Units are easy to calibrate without opening the case, reducing maintenance costs and downtime
 - All units include a NIST-traceable calibration certificate at no additional charge
 - Factory-tested for accuracy and reliability before shipment
 
Software Integration
Fluke’s Interface-it software supports:
- Set-point and ramp rate control
 - Real-time temperature logging
 - Electronic strip chart creation
 - Thermal switch test automation with data collection
 - Windows-based interface with intuitive graphical controls
 
Whether you need basic control or full automation, Fluke has a software solution ready.
Fluke 9103 – Low-Temperature Field Dry-Well
- Temperature Range: Down to –25 °C (actual, not below ambient)
 - Stability: ±0.02 °C
 - Display Accuracy: ±0.25 °C across full range
 - Speed:
- Reaches 0 °C in 8 minutes
 - Reaches 100 °C in 6 minutes
 
 
Key Advantage:
Many competitors advertise –45 °C below ambient, which only reaches around –20 °C. The 9103 delivers a true –25 °C in standard room conditions—no walk-in freezer required.
Insert Options:
Choose from four removable inserts to suit your calibration needs:
- Insert A: One well each from 1/16” to 1/2”
 - Insert B: Two wells each of 3/8”, 1/4”, and 3/16” (ideal for comparison calibrations)
 - Insert C: Six 1/4” wells for multiple probe calibrations
 - Insert D: Three pairs of metric-sized wells
 
Fluke 9140 – Mid-Temperature Field Dry-Well
- Temperature Range: 35 °C to 350 °C
 - Stability: ±0.05 °C or better
 - Uniformity:
- 0.1 °C in small-diameter wells
 - 0.4 °C in largest-diameter wells
 
 - Speed: Reaches max temperature in 12 minutes
 - Size: Weighs only 6 lbs, easily portable with one hand
 - Display Accuracy: ±0.5 °C
 
For improved calibration accuracy, use an external thermometer alongside the built-in display.
Insert Options:
Three removable inserts available to accommodate various probe sizes.
Why Choose the 9103 or 9140?
| Model | Temperature Range | Stability | Display Accuracy | Key Benefits | 
| 9103 | –25 °C to 110+ °C | ±0.02 °C | ±0.25 °C | True sub-ambient performance without freezer | 
| 9140 | 35 °C to 350 °C | ±0.05 °C | ±0.5 °C | Light, fast, and ideal for field portability | 
Both models are:
- Reliable for industrial and lab environments
 - Versatile with multiple insert options
 - Backed by Fluke’s proven calibration technology
 
Specifications: Fluke Calibration 9103/9140 Field Dry-Well
| Specifications | 9103 | 9140 | 
| Range | –25°C to 140°C (–13°F to 284°F) at 23°C ambient  | 35°C to 350°C (95°F to 662°F)  | 
| Accuracy | ±0.25°C (holes greater than 1/4" [6.35mm]: ±1°C) | ±0.5°C (holes greater than 1/4" [6.35mm]: ±1°C) | 
| Stability | ±0.02°C at –25°C ±0.04°C at 140°C  | ±0.03°C at 50°C ±0.05°C at 350°C  | 
| Well-to-well uniformity | ±0.1°C between similarly sized wells | ±0.1°C with similarly sized wells | 
| Heating times | 18 minutes from ambient to 140°C | 12 minutes from ambient to 350°C | 
| Cooling times | 20 minutes from ambient to –25°C | 15 minutes from 350°C to 100°C | 
| Stabilization time | 7 minutes | 7 minutes | 
| Immersion depth | 124 mm (4.875 in) | 124 mm (4.875 in) | 
| Inserts | Insert A, B, C, or D included (specify when ordering) | |
| Outside insert dimensions | 31.8 mm dia. x 124 mm (1.25 x 4.88 in) | |
| Computer interface | RS-232 included with free Interface-it software (Model 9930) | |
| Power | 115 V AC (±10%), 1.3 A or 230 V AC (±10%), 0.7 A, switchable, 50/60 Hz, 150 W | 115 V AC (±10%), 4.4 A or 230 V AC (±10%), 2.2 A, switchable, 50/60 Hz, 500 W | 
| Size (W x H x D) | 143 x 261 x 245 mm (5.63 x 10.25 x 9.63 in)  | 152 x 86 x 197 mm (6 x 3.375 x 7.75 in)  | 
| Weight | 5.7 kg (12 lb) | 2.7 kg (6 lb) | 
| NIST-traceable certificate | Data at –25°C, 0°C, 25°C, 50°C, 75°C, 100°C, and 140° | Data at 50°C, 100°C, 150°C, 200°C, 250°C, 300°C, and 350°C | 
Models: Fluke Calibration 9103/9140 Field Dry-Well
Insert, blank (cold side)
-25°C to 140°C
Insert "A", miscellaneous (cold side)
–25°C to 140°C
Insert "B", comparison (cold side)
–25°C to 140°C
Insert "C", six 1/4 in wells (cold side)
–25°C to 140°C
Insert "D", comparison - metric (cold side)
–25°C to 140°C
Insert, blank
35°C to 350°C
Insert "A"
35°C to 350°C
Insert "B"
35°C to 350°C
Insert "C"
35°C to 350°C
Insert "D"
35°C to 350°C
Manuals + resources: Fluke Calibration 9103/9140 Field Dry-Well
- Common Problems in Achieving Maximum Performance from Dry-Well Thermometer Calibrators
 - How to calibrate an RTD or Platinum Resistance Thermometer (PRT)
 - Improving Loop Calibration Temperature Accuracy
 - Selecting an Industrial Temperature Calibrator
 - Temperature Calibration Equipment: A Technician's Guide
 - Temperature measurement and calibration: What every instrument technician should know
 - The Development of a High-Temperature PRT Calibration Process Based on Dry-Block Calibrators
 
