One of Hart’s best-selling products is the Tweener thermometer, and there’s a reason. No other company, not one, has a thermometer that comes close to the performance and features of the Tweener for anywhere near its price.

The Model 1502A Tweener features accuracy up to ±0.006°C.  In addition, it reads both 100-ohm and 25-ohm probes, has a resolution of 0.001°C across its entire range and is the smallest unit in the industry. It also has an optional battery pack for completely portable operation.

Each Tweener is programmable to match any probe’s constants for maximum linearity and accuracy. All probe constants and coefficients are programmed through simple, front-panel keystrokes. Temperature is displayed in °C, °F, °K, or resistance in ohms.

The 1502A accurately measures the resistance of the probe and then converts the resistance to a temperature value using its built-in algorithms.

For convenience, the 1502A reads the common industrial grade IEC-751 or “385” ALPHA RTD without any programming. Enter the actual R0 and ALPHA of the individual probe for increased accuracy. For maximum accuracy, use the ITS-90 formulas. The Tweener accepts the subranges 4 and 6 through 11.

ITS-90 formulas reside in its firmware. If your probe has been calibrated for any of the subranges of the ITS-90, you simply enter the coefficients directly into the Tweener.

Each thermometer comes complete with an RS-232 interface for automation of temperature data collection, calibrations, or process control functions. An IEEE-488 interface is available as an option.

The 1502A is calibrated digitally using the front-panel buttons. You never have to open the box to calibrate it. This calibration protocol further reduces the cost of the 1502A. It goes where you go and works the way you want it to.

Want more? There are two more Tweeners for specific applications, including the Model 1503 High Temperature PRT Readout and the Model 1504 Thermistor Readout.

With our Model 9934 LogWare, all three Tweener models may be used for real-time data acquisition. Collect data and analyze it graphically or statistically. Additionally, Tweeners may be used as reference thermometers with our MET/TEMP II software. 

If you want freedom from AC power in the field or on the plant floor, order Model 2502 and we’ll install a DC power board in your Tweener. Then you can connect your own 12-volt DC power or order Hart’s 9313 Battery Pack. Our battery gives you three to eight hours between charges. It includes a charger and a nylon pouch with a belt clip.

Each Tweener and its accompanying probe (sold separately) have their own individual calibration reports. Overall system error can be calculated from the individual errors, rendering the added cost of system data unnecessary. However, for those requiring it, system data is available at two or more temperatures of your choice. (See Calibration Model 1929-X )

Four channels for PRTs, thermistors, and thermocouples  Displays eight user-selected data fields from any channel.  Logs up to 8,000 readings with date and time stamps.  Battery provides eight hours of continuous operation. 

Hart’s Model 1529 Chub-E4 Thermometer gives you four channels, three major sensor types, lab-quality accuracy, and a ton of great features, all at a price you’ll love. 

The Chub-E4 has four inputs for reading four different sensors simultaneously, and we’ll configure those inputs in any of three different ways according to your preference. Choose four channels of thermocouple inputs, four channels of PRT/thermistor inputs, or two channels of each. With this thermometer, reading thermocouples, PRTs, and thermistors accurately from the same device is no problem. 

100-ohm or 25-ohm PRTs and RTDs are read using ITS-90, IEC-751 (DIN), or Callendar-Van Dusen conversion methods. Typical accuracies include ±0.004°C at –100°C and ±0.009°C at 100°C.

PRTs and thermistors connect easily to the 1529 using Hart’s patented mini DWF connectors, which accept bare wire, spade lug, or mini banana plug terminations. Thermocouples connect using standard or miniature terminations. Measurements are taken each second and can be taken simultaneously or sequentially. A special high-speed mode allows measurements on one channel to be taken at the rate of 10 per second. 

If you think three sensor types and four inputs sounds versatile, wait until you see the display panel on the Chub-E4. Displaying measurements in °C, °F, K, ohms, or millivolts and choosing temperature resolution from 0.01 to 0.0001 are just the beginning. 

You can also select any eight items from our long list of displayable data fields to view on-screen. Choose statistical functions such as averages, standard deviations, and spreads; choose probe information such as probe type and serial number; choose T1-T2 functions using inputs from any two channels; or choose utility functions such as the date, time, and battery power level. You can even save up to 10 screen configurations for easy recall. 

The push of a single front-panel button also brings up a simple menu system to easily guide you through all the internal setup and memory options of the 1529. Probe coefficients, sample intervals, communication settings, password settings, and a host of other functions are all easily accessible. 

The memory and communications capabilities of the Chub-E4 make it perfect for benchtop thermometry, on-site measurements, lab calibration work, and remote data logging. Optional software packages from Hart make this one of the most powerful thermometers on the market. 

With battery power and memory to store up to 8,000 measurements (including date and time stamps) at user-selected intervals, the 1529 has plenty of data logging capability. Store 100 individual measurements or any number of automatic log sessions (up to 8,000 readings), each tagged with an identifying session label. Fourteen different logging intervals may be selected, from 0.1 second to 60 minutes.   

With Hart’s 9935 LogWare II, data may be quickly downloaded to your PC for complete graphical and statistical analysis. Separate log sessions may even be automatically downloaded to separate files based on session labels. With this software, the 1529 can even be used for real-time data logging. Log four channels at once directly to your PC with virtually no limit to the number of data points you take. You can analyze data, set alarm events, and even set delayed start and stop times. 

With MET/TEMP II software, the Chub-E4 may be integrated into a completely automated calibration system. Use one input for your reference thermometer and calibrate up to three other thermometers automatically. An RS-232 port is standard on every unit. An IEEE-488 port is optional.