Process Tools

Product overview: Fluke 9132/9133 Portable Infrared Calibrator with Blackbody Source

Great for clean room environments

Calibration baths are the most stable and uniform temperature sources available, but they aren’t a good fit for clean rooms. The size of a bath limits its portability, and bath fluids can easily spill and give off vapors. The 9190A Ultra-Cool Field Metrology Well is a great alternative. Its wide temperature range brackets the coldest and highest temperature ranges required for pharmaceutical, biomedical and food processing applications. The 9190A is small and lightweight, making it easy to transport. And since it does not use heat transfer fluids, clean rooms stay clean. The 9190A cooling and heating times are faster than a calibration bath—that means calibration work gets done more quickly.

An accurate temperature source is critical for dependable process measurements

Unreliable process measurements can have a damaging impact on business, leading to poor product quality, recalls, fines, waste, and lost profits. Ultimately, measurements are only as good as the temperature sources used to calibrate the measurement equipment. The 9190A Ultra-Cool Field Metrology Well incorporates the best technology and design expertise gained from decades of dry-block development experience. The 9190A conforms with EURAMET cg-13 guidelines for best measurement practices for temperature block calibrators. As a result, you can be assured that the 9190A specifications for accuracy, stability, axial (vertical) uniformity, radial (well-to-well) uniformity, loading, and hysteresis have been thoroughly and carefully defined and tested. With a 9190A Ultra-Cool Field Metrology Well, you can be confident you’re using the most accurate and stable ultra-cool dry-block calibrator available. And that will have a positive impact on your business.

Precision thermometer readouts for laboratory and field use

1502A Tweener PRT Readout

The Fluke Calibration 1502A Tweener offers precision temperature measurement with:

• Accuracy up to ±0.006 °C
• Resolution of 0.001 °C across the entire range
• Compatibility with 100-ohm, 25-ohm, and 10-ohm RTD probes
• Smallest unit in its class, ideal for field or bench use
• Optional 9320A Battery Pack for full portability

Advanced Features

• Programmable to match a probe’s constants for maximum linearity and accuracy
• Displays temperature in °C, °F, K, or resistance in ohms
• Reads standard industrial IEC-751 / “385 ALPHA” RTDs with no programming required
• Accepts ITS-90 subranges 4 and 6–11, with formulas built into firmware
• Calibration is done digitally via front-panel—no need to open the device
• Comes with RS-232 interface; optional IEEE-488 interface available

1504 Tweener Thermistor Readout

Need higher precision in a narrower temperature range? The Model 1504 Tweener offers:

• Accuracy up to ±0.002 °C
• Resolution of 0.0001 °C
• Designed specifically for thermistors—more robust, shock-resistant sensors with faster response times
• Ideal for applications requiring high sensitivity and reliability in limited temperature spans

Calibration and Probe Integration

• Each Tweener and its compatible probe (sold separately) include individual calibration reports
• System data is available upon request at two or more temperatures for high-precision needs (Calibration Model 1929-X)
• Users can calculate system accuracy using individual device specifications—no need to purchase system-level data unless required

Software Compatibility

Enhance your workflow with Fluke software tools:

• 9934 LogWare: Real-time data acquisition, graphing, and analysis
• MET/TEMP II: Use Tweeners as reference thermometers for automated calibrations

Optional Battery Pack

Take your Tweener on the road with the 9320A Battery Pack:

• Provides up to 36 hours of portable operation between charges
• Perfect for fieldwork or locations without direct power access

• Accredited radiometric calibration included
• Accurate, reliable performance from –15 °C to 500 °C
• Large target size of 152 mm (6 in) is required for calibrating most thermometers.
• Light instrument weight of 8.6 kg (19 lbs) makes it easy to lift and carry.

Portable and extremely stable

Need portability and extreme stability? Fluke Calibration Micro-Baths have both. We invented the Micro-Bath. And, while many have tried to duplicate it, none of them use proprietary Fluke Calibration controllers, so none of them deliver performance like a Fluke Calibration bath. Micro-Baths can be used anywhere for any type of sensor. The 6102 weighs less than 4.5 kg (10 lb.), with the fluid. It’s lighter and smaller than most dry-wells, has a spill-proof lid, and is easier to carry than your lunch. You can take it where you need to go without carts or excessive effort. Micro-Baths can even be transported with the fluid in them.

Wherever you go with your Micro-Bath, you can count on its performance. Each model is stable to ±0.03 °C or better, depending on the fluid you use. Uniformity is ±0.02 °C or better for low uncertainties using a reference thermometer. Display accuracy has been improved to ±0.25 °C for quick calibrations without a reference thermometer. In short, you get the stability and precision of a liquid bath in a dry-well-sized package. Don’t be fooled by competitors who pour oil into a dry-well and call it a bath. Micro-Baths are maximized for true fluid-bath performance.

With a 48 mm (1.9-inch) diameter, 140 mm (5.5-inch) deep tank, a Micro-Bath can calibrate any type of sensor including short, square, or odd-shaped sensors. The problems of fit and immersion are virtually eliminated by using a fluid medium rather than a dry-block calibrator. Micro-Baths are perfect for liquid-in-glass and bimetal thermometers.

The 6102 has a temperature range from 35 °C to 200 °C, the 7102 covers –5 °C to 125 °C, and the 7103 extends from –30 °C to 125 °C. Stability, uniformity, and accuracy specifications cover the entire range for each bath, not just the best temperature.

All Micro-Baths have RS-232 ports and can be used with MET/TEMP II software (described on page 81). Also included are contacts to calibrate a thermal switch, eight set-point memory storage, ramp-rate adjust, and over-temperature safety cutout.

You may have noticed we haven’t touted our CFC-free refrigeration. Yes, cold Micro-Baths are CFC-free, and also compressor-free. That’s right—no heavy, noisy compressor to lug around. We achieve our temperature range and stability with only one moving part. This means more durability and less weight. Fluke Calibration manufactures and sells temperature calibration baths of every size and shape, and now we have the smallest and lightest baths in the industry to go with the dozens of other models we make.

Look at the specs, price, and value of these portable instruments and you’ll know why Fluke Calibration is the number-one company in this business.

Four times more calibration throughput with twice the accuracy of Micro-Baths and dry-block calibrators

Process manufacturing plants for pharmaceuticals, biotechnology, and food production utilize many sanitary temperature sensors that require regular calibration. Production must stop while the calibrations are taking place. Therefore, more calibration throughput means less plant downtime. And in businesses where even a few tenths of a degree Celsius can cost thousands of dollars in ruined product, temperature accuracy is crucial to maintaining quality.

The Fluke Calibration 6109A and 7109A Portable Calibration Baths let process industry professionals calibrate four times more sanitary sensors per batch in less time and with twice the accuracy of other baths in this class. Up to four tri-clamp sanitary sensors fit easily into these baths for calibration at ± 0.1 °C temperature display accuracy. Throughput is even higher for sanitary RTDs with small or no flanges.

Two bath models cover a wide temperature range: 35 °C to 250 °C for the 6109A and -25 °C to 140 °C for the 7109A. Each model offers a “-P” version that includes process electronics for connecting an external reference probe.

Professionals working in clean process industries, including facilities managers, production engineers and calibration technicians, prefer these baths for a variety of reasons.

Facilities managers who need to meet U.S. FDA and ISO clean room standards like the baths’ stainless steel casing that stands up to harsh cleaning solutions. They depend on the 6109A and 7109A to help maintain the accuracy of the plant’s temperature sensors, thus reducing the possibility of an expensive product batch loss.

Production engineers also appreciate the baths’ accuracy, which helps them control sensor out-of-tolerance conditions. Moreover, they prefer to use a bath designed specifically for clean room calibration throughput. No more need to make do with equipment designed for some other application.

Calibration technicians who perform calibrations on platforms, in crawl spaces, and other hard-to-reach parts of the plant enjoy the portability and clean room compatibility (i.e. easy to sanitize, don’t harbor bacteria) of these baths.

Global Fluke Calibration service and support ensure that your 6109A and 7109A baths will give you years of service that you can trust.

Calibrate more sanitary sensors at a time – with confidence

The 6109A and 7109A baths calibrate most temperature sensor applications used in clean process manufacturing, including pharmaceutical bioreactors (-10 C to 100 °C), chemical reactors (200 °C), steam-in-place process (122 °C to 140 °C), autoclave sterilization (120 °C to 135 °C), food storage freezers (-25 °C), and food processing (0 °C to 220 °C).

A large tank volume (112 mm square tank opening x 154 mm depth) lets you immerse up to four sanitary sensors at the same time. Calibrate a batch of odd shaped sensors of varying lengths and diameters, and still have room for a reference thermometer. Fast heating and cooling times let you get the job done without spending a lot of time waiting for the bath to come to temperature and stabilize. Increase your sanitary sensor calibration throughput and decrease expensive production downtime.

Excellent system display accuracy of ± 0.1 °C. Accuracy covers all sources of error including calibration uncertainty, stability, uniformity, and repeatability. NVLAP accredited calibration is included standard. Fluke Calibration’s high metrological standards and conservative specifications mean you can have confidence in the measurements you make with the 6109A and 7109A Portable Calibration Baths.

Take these portable baths almost anywhere, including the clean room

The 6109A weighs 16 kilograms (35 pounds) and the 7109A weighs 20 kilograms (44 pounds). They each feature a fixed, non-rotating bail handle, enabling most people to carry a bath with one hand. Single-handed carrying comes in handy when the job includes walking up and down stairs, across catwalks, and into other hard-to-reach environments. Two recessed handles on the bottom of each bath also make it easy to move from a shelf to a cart or benchtop. A sealed lid protects against fluid spills while moving the bath.

Stainless steel casing stands up to the harsh chemicals used to sterilize equipment for clean room use. Synthetic materials used for decals, keypads and feet do not harbor bacteria. The keypad is sealed against moisture ingress to protect against damage during cleaning or in non-controlled environments.

Easy to use and maintain

Each bath features a large color display that indicates date and time, bath fluid temperature, setpoint temperature, control indicator when the fluid is at setpoint, and heating status. A ready indicator changes color from amber to green, giving you 360-degree visual indication when the bath fluid has reached its setpoint temperature and is ready for you to start making measurements.

A hot warning indicator lights up if the fluid temperature reaches above 60 °C, warning the operator that the bath fluid and tank area are hot and should not be touched.

An adjustable probe fixture holds up to four tri-clamp sensors securely inside the tank opening during calibration. An optional single probe clamp kit holds a reference probe.

Fluid spills create mess and potential safety hazards. The 6109A and 7109A include an overflow tube that directs excess bath fluid into an optional overflow container. A drain tube makes it easy to remove bath fluid for replacement or transport.

I own a Fluke Calibration Micro-Bath. Why do I need a 6109A or 7109A bath?

If you already own a Fluke Calibration Micro-Bath or dry-block calibrator, thank you for being a customer! We hope you are enjoying the portability and stability of these popular products.

However, there are a few reasons why you should consider adding a 6109A or 7109A bath:

Errors of just a few tenths of a degree Celsius can cause expensive losses in ruined product. The 6109A and 7109A baths are twice as accurate as a Micro-Bath, helping you to reduce this risk. The 6109A and 7109A have four times the calibration throughput of a Micro-Bath, which can only calibrate a single tri-clamp sensor at a time. They’re made with materials that don’t harbor bacteria. Their stainless steel panels and tank are easy to clean and rust resistant–perfect for clean room use. We hope you will continue to use your Fluke Calibration Micro-Bath for many years to come. The 6109A or 7109A baths will also serve you well if you need the throughput, accuracy, and clean room readiness that they provide.

Backed by global Fluke support and service

The 6109A and 7109A are designed to meet demanding Fluke Calibration metrology specifications, so you can trust that they will perform the way we say they will. Need assistance? We offer world-class support both before and after the sale, via online chat, email, telephone and through our service organizations. Rest easy knowing the value of your investment will be preserved now and into the future.

• Temperature ranges from –10°C to 375°C.
• Accuracy to ±0.25°C, with stability of ±0.05°C at 0°C.
• Equipped with an RS-232 interface for connectivity.

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

• Lightweight, portable, and fast
• Built-in two-channel readout for PRT, RTD, thermocouple, 4-20 mA current
• True reference thermometry with accuracy to ±0.01 °C
• On-board automation and documentation
• Metrology performance in accuracy, stability, uniformity, and loading

Built-in features to address large workloads and common applications

Whether you need to calibrate 4-20 mA transmitters or a simple thermostatic switch, a Field Metrology Well is the right tool for the job. With three models covering the range of –25 °C to 660 °C, this family of Metrology Wells calibrates a wide range of sensor types. The optional process version (models 914X-X-P) provides a built-in two-channel thermometer readout that measures PRTs, RTDs, thermocouples, and 4-20 mA transmitters which includes the 24 V loop supply to power the transmitter.

Each process version accepts an ITS-90 reference PRT. The built-in readout accuracy ranges from ±0.01 °C to ±0.07 °C depending on the measured temperature. Reference PRTs for Field Metrology Wells contain individual calibration constants that reside in a memory chip located inside the sensor housing, so sensors may be used interchangeably. The second channel is user-selectable for 2-, 3-, or 4-wire RTDs, thermocouples, or 4-20 mA transmitters. For comparison calibration, don’t hassle with carrying multiple instruments to the field. Field Metrology Wells do it all as a single instrument.

Traditionally, calibrations of temperature transmitters have been performed on the measurement electronics, while the sensor remained uncalibrated. Studies have shown, however, that typically 75% of the error in the transmitter system (transmitter electronics and temperature sensor) is in the sensing element. Thus, it becomes important to calibrate the whole loop—both electronics and sensor.

The process option of Field Metrology Wells makes transmitter loop calibrations easy. The transmitter sensor is placed in the well with the reference PRT and the transmitter electronics are connected to the front panel of the instrument. With 24 V loop power, you are able to power and measure the transmitter current while sourcing and measuring temperature in the Field Metrology Well. This allows for the measurement of as-found and as-left data in one self-contained calibration tool.

All Field Metrology Wells allow for two types of automated thermostatic switch test procedures—auto or manual setup. Auto setup requires the entry of only the nominal switch temperature. With this entry, it will run a 3-cycle calibration procedure and provide final results for the dead band temperature via the display. If you need to customize the ramp rate or run additional cycles, the manual setup allows you to program and run the procedure exactly how you would like. Both methods are fast and easy and make testing temperature switches a virtual joy!

Metrology performance for high-accuracy measurements

Unlike traditional dry-wells, Field Metrology Wells maximize speed and portability without compromising the six key metrology performance criteria laid out by the EA: accuracy, stability, axial (vertical) uniformity, radial (well-to-well) uniformity, loading, and hysteresis. All criteria are important in ensuring accurate measurements in all calibration applications. Field Metrology Well displays are calibrated with highquality traceable and accredited PRTs. Each device (process and non-process versions) comes with an IEC-17025 NVLAP-accredited calibration certificate, which is backed by a robust uncertainty analysis that considers temperature gradients, loading effects, and hysteresis. The 9142 and 9143 have a display accuracy of ±0.2 °C over their full range, and the 9144 display accuracy ranges from ±0.35 °C at 420 °C to ±0.5 °C at ±660 °C. Each calibration is backed with a 4:1 test uncertainty ratio.

New control technology guarantees excellent performance in extreme environmental conditions. The 9142 is stable to ±0.01 °C over its full range and the mid-range 9143 is stable from ±0.02 °C at 33 °C and ±0.03 °C at 350 °C. Even at 660 °C, the 9144 is stable to ±0.05 °C. But this is not all! Thermal block characteristics provide radial (well-towell) uniformity performance to ±0.01 °C. Dual-zone control helps these tools achieve axial uniformity to ±0.05 °C at 40 mm (1.6 in).

Automation and documentation make each unit a turnkey solution

So you now have a precision calibration instrument that has field-ready characteristics, accredited metrology performance, built-in two-channel thermometry, and automation— what else could you ask for? How about all this and a turnkey solution that will automate and document the results?

The process versions of Field Metrology Wells have onboard non-volatile memory for documentation of up to 20 tests. Each test can be given a unique alphanumeric ID and will record block temperature, reference temperature, UUT values, error, date, and time. Each test can be easily viewed via the front panel. Use the 1586A Super-DAQ to automate temperature sensor calibration with these Field Metrology Wells.

Operation is as easy as 1-2-3

You’ll find Field Metrology Wells intuitive and easy to use. Each unit is equipped with a large, easy-to-read LCD display, function keys, and menu navigation buttons. Its “SET PT.” button makes it straightforward and simple to set the block temperature. Each product has a stability indicator that visually and audibly tells you the Field Metrology Wells is stable to the selectable criteria. Each unit offers preprogrammed calibration routines stored in memory for easy recall, and all inputs are easily accessible via the front panel of the instrument. Never buy a temperature calibration tool from a company that only dabbles in metrology (or doesn’t even know the word). Metrology Wells from Fluke are designed and manufactured by the same people who equip the calibration laboratories of the world’s leading temperature scientists. These are the people around the world who decide what a Kelvin is! We know a thing or two more about temperature calibration than the vast majority of the world’s dry-well suppliers. Yes, they can connect a piece of metal to a heater and a control sensor. But we invite you to compare all our specs against the few that they publish. (And by the way, we meet our specs!).

Small dry wells for big field applications

The 9142, 9143, 9144 Field Metrology Wells extend high performance to the industrial process environment by maximizing portability, speed, and functionality with little compromise to metrology performance.

Field Metrology Wells are packed with functionality and are remarkably easy to use. They are lightweight, small, and quick to reach temperature set points, yet they are stable, uniform, and accurate. These industrial temperature loop calibrators are perfect for performing transmitter loop calibrations, comparison calibrations, or simple checks of thermocouple sensors. With the “process” option, there is no need to carry additional tools into the field. This optional built-in two-channel readout reads resistance, voltage, and 4–20 mA current with 24 volt loop power. It also has on-board automation and documentation. Combined, the three models (9142, 9143, and 9144—each with a “process” option) cover the wide range of –25 °C to 660 °C.

High performance for the industrial environment

Field Metrology Wells are designed for the industrial process environment and fast speed to temperature. They weigh less than 8.2 kg (18 lb) and have a small footprint, which makes them easy to transport.

Field environment conditions are typically unstable, having wide temperature variations. Each Field Metrology Well has a built-in gradient-temperature compensation (patent pending) that adjusts control characteristics to ensure stable performance in unstable environments. In fact, all specifications are guaranteed over the environmental range of 13 °C to 33 °C.

• Exceptional stability (±0.005 °C) and axial uniformity (±0.02 °C over a 60 mm zone).
• Immersion depth to 203 mm (8 in)
• Optional ITS-90 reference input reads PRTs to ±0.006 °C
• Wide Temperature range from –45 °C to 700 °C

Display accuracy

Dry-wells are typically calibrated by inserting a calibrated PRT into one of the wells and making adjustments to the calibrator’s internal control sensor based on the readings from the PRT. This has limited value because the unique characteristics of the reference PRT, which essentially become “calibrated into” the calibrator, are often quite different from the thermometers tested by the calibrator. This is complicated by the presence of significant thermal gradients in the block and inadequate sensor immersion into blocks that are simply too short.

Metrology Wells are different. Temperature gradients, loading effects, and hysteresis have been minimized to make the calibration of the display much more meaningful. We use only traceable, accredited PRTs to calibrate Metrology Wells and our proprietary electronics consistently demonstrate repeatable accuracy more than ten times better than our specs, which range from ±0.1 °C at the most commonly used temperatures to ±0.25 °C at 661 °C.

An application note is available to help better understand the uncertainties mentioned above.

For even better accuracy, Metrology Wells may be ordered with built-in electronics for reading external PRTs with ITS-90 characterizations. (See sidebar, Built in Reference Thermometry)

Stability

Heat sources from Fluke Calibration have long been known as the most stable heat sources in the world. It only gets better with Metrology Wells. Both low-temperature units (Models 9170 and 9171) are stable to ±0.005 °C over their full range. Even the 700 °C unit (Model 9173) achieves stability of ±0.03 °C. Better stability can only be found in fluid baths and primary fixed-point devices. The “off-the-shelf controllers” used by most dry-well manufacturers simply can’t provide this level of performance.

Axial uniformity

The EA-10/13 document suggests that dry-wells should include a zone of maximum temperature homogeneity, which extends for 40 mm (1.54 in), usually at the bottom of a well. Metrology Wells, however, combine our unique electronics with dual-zone control and more well depth than is found in dry-wells to provide homogeneous zones over 60 mm (2.36 in). Vertical gradients in these zones range from ±0.02 °C at 0 °C to ±0.4 °C at 700 °C.

What’s more, Metrology Wells actually have these specifications published for each unit, and we stand by them.

Radial uniformity

Radial uniformity is the difference in temperature between one well and another well. For poorly designed heat sources, or when large-diameter probes are used, these differences can be very large. For Metrology Wells, we define our specification as the largest temperature difference between the vertically homogeneous zones of any two wells that are each 6.4 mm (0.25 in) in diameter or smaller. The cold units (9170 and 9171) provide radial uniformity of ±0.01 °C and the hot units (9172 and 9173) range from ±0.01 °C to ±0.04 °C (at 700 °C).

Loading

Loading is defined as the change in temperature sensed by a reference thermometer inserted into the bottom of a well after the rest of the wells are filled with thermometers, too.

For Metrology Wells, loading effects are minimized for the same reasons that axial gradients are minimized. We use deeper wells than found in dry-wells. And we utilize proprietary dual-zone controls. Loading effects are as minimal as ±0.005 °C in the cold units.

Hysteresis

Thermal hysteresis exists far more in internal control sensors than in good-quality reference PRTs. It is evidenced by the difference in two external measurements of the same set-point temperature when that temperature is approached from two different directions (hotter or colder) and is usually largest at the midpoint of a heat source’s temperature range. It exists because control sensors are typically designed for ruggedness and do not have the “strain free” design characteristics of SPRTs, or even most PRTs. For Metrology Wells, hysteresis effects range from 0.025 °C to 0.07 °C.

Immersion depth

Immersion depth matters. Not only does it help minimize axial gradient and loading effects, it helps address the unique immersion characteristics of each thermometer tested in the heat source. Those characteristics include the location and size of the actual sensor within the probe, the width and thermal mass of the probe, and the lead wires used to connect the sensor to the outside world. Metrology Wells feature well depths of 203 mm (8 in) in the Models 9171, 9172, and 9173. The Model 9170 is 160 mm (6.3 in) deep to facilitate temperature of –45 °C.

Other great features

A large LCD display, numeric keypad, and on-screen menus make use of Metrology Wells simple and intuitive. The display shows the block temperature, built-in reference thermometer temperature, cutout temperature, stability criteria, and ramp rate. The user interface can be configured to display in English, French, or Chinese.

All four models come with an RS-232 serial interface. All are also compatible with Model 9938 MET/TEMP II software for completely automated calibrations of RTDs, thermocouples, and thermistors.

Even without a PC, Metrology Wells have four different preprogrammed calibration tasks that allow up to eight temperature set points with “ramp and soak” times between each. There is an automated “switch test” protocol that zeros in on the “dead-band” for thermal switches. And a dedicated °C/ °F button allows for easy switching of temperature units.

Any of six standard inserts may be ordered with each unit, accommodating a variety of metric- and imperial-sized probe diameters. (See inset at right. Download the complete data sheet to view details.) And Metrology Wells are small enough and light enough to go anywhere.

9170

The Model 9170 achieves the lowest temperatures of the series, reaching –45 °C in normal room conditions. The 9170 is stable to ±0.005 °C over its full temperature range (up to 140 °C) and has 160 mm (6.3 in) of immersion depth. With axial uniformity of ±0.02 °C and radial uniformity of ±0.01 °C, this model delivers exceptional uncertainty budgets and is perfect for a variety of pharmaceutical and other applications.

Display accuracy

Dry-wells are typically calibrated by inserting a calibrated PRT into one of the wells and making adjustments to the calibrator’s internal control sensor based on the readings from the PRT. This has limited value because the unique characteristics of the reference PRT, which essentially become “calibrated into” the calibrator, are often quite different from the thermometers tested by the calibrator. This is complicated by the presence of significant thermal gradients in the block and inadequate sensor immersion into blocks that are simply too short.

Metrology Wells are different. Temperature gradients, loading effects, and hysteresis have been minimized to make the calibration of the display much more meaningful. We use only traceable, accredited PRTs to calibrate Metrology Wells and our proprietary electronics consistently demonstrate repeatable accuracy more than ten times better than our specs, which range from ±0.1 °C at the most commonly used temperatures to ±0.25 °C at 661 °C.

An application note is available to help better understand the uncertainties mentioned above.

For even better accuracy, Metrology Wells may be ordered with built-in electronics for reading external PRTs with ITS-90 characterizations. (See sidebar, Built in Reference Thermometry)

Stability

Heat sources from Fluke Calibration have long been known as the most stable heat sources in the world. It only gets better with Metrology Wells. Both low-temperature units (Models 9170 and 9171) are stable to ±0.005 °C over their full range. Even the 700 °C unit (Model 9173) achieves stability of ±0.03 °C. Better stability can only be found in fluid baths and primary fixed-point devices. The “off-the-shelf controllers” used by most dry-well manufacturers simply can’t provide this level of performance.

Axial uniformity

The EA-10/13 document suggests that dry-wells should include a zone of maximum temperature homogeneity, which extends for 40 mm (1.54 in), usually at the bottom of a well. Metrology Wells, however, combine our unique electronics with dual-zone control and more well depth than is found in dry-wells to provide homogeneous zones over 60 mm (2.36 in). Vertical gradients in these zones range from ±0.02 °C at 0 °C to ±0.4 °C at 700 °C.

What’s more, Metrology Wells actually have these specifications published for each unit, and we stand by them.

Radial uniformity

Radial uniformity is the difference in temperature between one well and another well. For poorly designed heat sources, or when large-diameter probes are used, these differences can be very large. For Metrology Wells, we define our specification as the largest temperature difference between the vertically homogeneous zones of any two wells that are each 6.4 mm (0.25 in) in diameter or smaller. The cold units (9170 and 9171) provide radial uniformity of ±0.01 °C and the hot units (9172 and 9173) range from ±0.01 °C to ±0.04 °C (at 700 °C).

Loading

Loading is defined as the change in temperature sensed by a reference thermometer inserted into the bottom of a well after the rest of the wells are filled with thermometers, too.

For Metrology Wells, loading effects are minimized for the same reasons that axial gradients are minimized. We use deeper wells than found in dry-wells. And we utilize proprietary dual-zone controls. Loading effects are as minimal as ±0.005 °C in the cold units.

Hysteresis

Thermal hysteresis exists far more in internal control sensors than in good-quality reference PRTs. It is evidenced by the difference in two external measurements of the same set-point temperature when that temperature is approached from two different directions (hotter or colder) and is usually largest at the midpoint of a heat source’s temperature range. It exists because control sensors are typically designed for ruggedness and do not have the “strain free” design characteristics of SPRTs, or even most PRTs. For Metrology Wells, hysteresis effects range from 0.025 °C to 0.07 °C.

Immersion depth

Immersion depth matters. Not only does it help minimize axial gradient and loading effects, it helps address the unique immersion characteristics of each thermometer tested in the heat source. Those characteristics include the location and size of the actual sensor within the probe, the width and thermal mass of the probe, and the lead wires used to connect the sensor to the outside world. Metrology Wells feature well depths of 203 mm (8 in) in the Models 9171, 9172, and 9173. The Model 9170 is 160 mm (6.3 in) deep to facilitate temperature of –45 °C.

Other great features

A large LCD display, numeric keypad, and on-screen menus make use of Metrology Wells simple and intuitive. The display shows the block temperature, built-in reference thermometer temperature, cutout temperature, stability criteria, and ramp rate. The user interface can be configured to display in English, French, or Chinese.

All four models come with an RS-232 serial interface and the Model 9930, Interface-it software. All are also compatible with Model 9938 MET/TEMP II software for completely automated calibrations of RTDs, thermocouples, and thermistors.

Even without a PC, Metrology Wells have four different preprogrammed calibration tasks that allow up to eight temperature set points with “ramp and soak” times between each. There is an automated “switch test” protocol that zeros in on the “dead-band” for thermal switches. And a dedicated °C/ °F button allows for easy switching of temperature units.

Any of six standard inserts may be ordered with each unit, accommodating a variety of metric- and imperial-sized probe diameters. (See inset at right. Download the complete data sheet to view details.) And Metrology Wells are small enough and light enough to go anywhere.

9170

The Model 9170 achieves the lowest temperatures of the series, reaching –45 °C in normal room conditions. The 9170 is stable to ±0.005 °C over its full temperature range (up to 140 °C) and has 160 mm (6.3 in) of immersion depth. With axial uniformity of ±0.02 °C and radial uniformity of ±0.01 °C, this model delivers exceptional uncertainty budgets and is perfect for a variety of pharmaceutical and other applications.

• Exceptional stability (±0.005 °C) and axial uniformity (±0.02 °C over a 60 mm zone).
• Immersion depth to 203 mm (8 in)
• Optional ITS-90 reference input reads PRTs to ±0.006 °C
• Wide Temperature range from –45 °C to 700 °C

Ultra-Compact, Reliable, and Designed for Complete Immersion

Total Flexibility for Extreme Environments

The Fluke 5606 Full Immersion Platinum Resistance Thermometer (PRT) offers an unmatched solution for applications where full immersion of the probe—including transition junction and lead wires—is required. With a compact length of just two inches (50 mm) and a sheath diameter of only 1/8 inch (3.1 mm), the 5606 delivers accuracy and durability in the tightest spaces.

Key Features and Benefits

• Truly Full Immersion – No need to calculate minimum immersion depth. Simply immerse the entire probe, transition junction, and lead wires over the entire operating range—from –200 °C to 160 °C—in either non-corrosive liquids or dry mediums.
• High Accuracy in a Compact Size – Achieve calibration accuracies as good as ±0.05 °C, thanks to the specially constructed 100 Ω precision sensing element (alpha = 0.00385) that also blocks moisture ingress.
• Superior Moisture Protection – Single-conductor enameled copper lead wires prevent moisture from wicking into the sensing element, offering better protection than traditional stranded leads.
• Flexible and Easy Installation – Lead wires measure no greater than 0.2 mm in diameter, making it simple to route through tight spaces—such as a freezer door—without energy loss.
• Proven Durability – The 5606 has demonstrated excellent performance in heat transfer fluids like silicone oil, mineral oil, ethanol, and even liquid nitrogen, with no loss of integrity in the transition junction or lead wire insulation.

Engineered for Demanding Applications

The 5606 Full Immersion PRT is specifically designed to thrive in extreme environments. Both the transition junction and lead wires are built to endure temperatures covering the full probe range, ensuring complete reliability in challenging conditions.

“Immersion” means exposure to extreme temperatures—not just being submerged in a liquid—making the 5606 ideal for a wide variety of rigorous uses.

The 5608 comes with a one-eighth inch (3.18 mm) diameter sheath in lengths of 9 inches or 12 inches. The 5609 comes with a one-quarter inch (6.35 mm) diameter sheath in lengths of 12 inches, 15 inches, and 20 inches; or with a 6 mm diameter in lengths of 300 mm, 400 mm, or 500 mm.

When looking for improved response time and reduced stem effect in shallow immersion, look for small diameter probes, because the measurement error called stem effect is caused by the diameter of the stem rather than the length of the stem.

Both of these probes have Inconel™ sheaths and are made using a special manufacturing process, giving them great precision over a wide temperature range. The sensors for these probes are reference-grade platinum and feature four-wire connections with less noisy measurements than two-wire counterparts.

As standard, each probe includes its resistance value at the triple point of water. If calibration is desired, you can order a NVLAP-accredited calibration from our laboratory; lab code 200348-0. On the report of calibration, you’ll get the test data and the ITS90 calibration coefficients that you can easily input into any Fluke Calibration thermometer. If you order your probe with an smart connector, we’ll program the coefficients directly into your connector, which loads the coefficients for you when you plug it into our 1524 Handheld Thermometer.