THX-400-H

Supported Applications

The THX-400-H Series is an economical, accurate handheld thermistor probe built around an easy-grip molded utility handle. It is designed for portable temperature measurement wherever a durable, quickly deployed sensor is needed on the bench, on the production floor, or in the field. The probe can be stored in tool boxes or other locations for easy access, making it well suited to spot checks, maintenance rounds, and routine process verification.

Each probe uses a stainless steel sheath and a retractable cable, so the sensor can be extended to reach the measurement point and then drawn back for tidy storage. The stripped-lead termination connects readily to panel meters, data loggers, and handheld instruments, while the optional phone plug termination allows quick mating with compatible readouts. For calibration support, the CL26 high-precision handheld calibrator is offered as an accessory.

Operating Conditions & Performance

The THX-400-H Series carries a maximum temperature rating of 150°C at the sensor and 135°C at the handle, defining the safe envelope for both the wetted probe tip and the operator-held grip. Staying within these limits protects the molded handle while allowing the sensor to read across a broad range of everyday process temperatures.

Measurement accuracy is ±0.2°C @ 0 to 70°C, and each thermistor is specified at a nominal resistance of 2252 Ω at 25°C. Interchangeability across units is held to ±0.2°C over the same 0 to 70°C band, so probes can be swapped without recalibrating the readout.

The sensing element is housed in a 4.5 mm diameter sheath of 300 Series stainless steel, providing mechanical strength and corrosion resistance. The retractable cable extends to 1.5 m, giving practical reach between the measurement point and the instrument.

Configuration Options

Variants within the THX-400-H Series differ along two dimensions: sheath length and cable termination. Longer sheaths allow the sensor to reach deeper into vessels, ducts, or stacked material, while the termination choice determines how the probe connects to your instrument.

• Sheath length is encoded in the model number, following the pattern THX-400-H-<SHEATH LENGTH>. Offered lengths are 300 mm, 450 mm, and 600 mm.
• Cable termination is either standard stripped leads or, by adding the -PP suffix, an optional phone plug connector for an additional cost.

Across every length and termination, the core specifications remain consistent: a 2252 Ω nominal resistance at 25°C, ±0.2°C interchangeability, a 4.5 mm diameter sheath, and the same 300 Series stainless steel construction.

Key Product Differences

The series comprises six catalog models. Each base length is available with standard stripped-lead termination or with the phone plug option denoted by the -PP suffix:

• THX-400-H-12 — 300 mm sheath, retractable cable with stripped leads
• THX-400-H-12-PP — 300 mm sheath with phone plug termination
• THX-400-H-18 — 450 mm sheath, retractable cable with stripped leads
• THX-400-H-18-PP — 450 mm sheath with phone plug termination
• THX-400-H-24 — 600 mm sheath, retractable cable with stripped leads
• THX-400-H-24-PP — 600 mm sheath with phone plug termination

As an example order, THX-400-H-12 is a utility handle probe 300 mm long with a retractable cable and stripped-lead termination, while THX-400-H-12-PP is the same probe supplied with a phone plug termination.