HH307-308

Supported Applications

The HH308 is a low-cost, pocket-sized digital thermometer designed for use with Type K thermocouples. As a dual-input (2-channel) handheld with a 4-digit LCD, it lets a technician monitor two temperatures at once and switch the display between °C and °F, making it a practical everyday tool for field service, laboratory checks, QA sampling, and equipment monitoring.

Readings conform to National Bureau of Standards and EC94 temperature/voltage tables for K-type thermocouples, so measurements stay traceable and repeatable. Standard minimum/maximum reading and reading-hold functions help capture peaks and freeze a value while recording. Each unit comes complete with a beaded-wire Type K thermocouple (one per input), a 9V battery, an operator's manual, and a NIST certificate (no points).

Within the HH300 mini-thermometer family, the HH308 is the economical Type K instrument; a Type J/K sibling adds a PC interface option, but the HH308 focuses on rugged, straightforward two-channel temperature measurement.

Operating Conditions & Performance

The HH308 measures Type K thermocouples across -200 to 1370°C (-328 to 2498°F) with a resolution of 0.1°C/0.1°F. Its headline accuracy is 0.3% rdg + 1°C (2°F). Note that the basic accuracy specification does not include probe error; refer to the probe's own specification for additional detail. For ambient temperatures from 0°C to 18°C or above 28°C, an additional tolerance of ±0.01% of reading + 0.03°C (±0.01% of reading + 0.05°F) applies.

Environmental and power specifications include:

• Input protection: 60 Vdc or 24 Vrms AC maximum
• Power: 9V battery (MN 1604), with up to 120 hour battery life on alkaline cells
• Operating range: 0 to 40°C (32 to 104°F), <80% RH
• Storage range: -10 to 60°C (14 to 140°F), <80% RH

The instrument weighs approximately 200 g (7 oz), measures 164 H x 54 W x 34 mm D (6.5 x 2.1 x 1.3"), and is CE marked with ISO 9001 and ISO 14001 manufacturing credentials, backed by a 1 YEAR WARRANTY.

Configuration Options

Although offered as a single dual-input model, the HH308's accuracy is tiered by measurement sub-range rather than being uniform across the full span. Within the Celsius scale, the meter holds ±0.3% reading + 1°C from -200°C through 400°C, easing to ±0.5% reading + 1°C across the upper 400°C to 1370°C span. Both channels accept Type K thermocouples and share the same 0.1°C/0.1°F resolution and switchable °C/°F display.

Bench calibration is trimmed against room-temperature references (23 ± 5°C), with adjustment points such as 0°C and 180°C held to ±0.1°C and 1000°F held to ±0.1°F, ensuring consistent two-channel readings straight out of calibration.

Key Product Differences

The series is built around a single meter:

• HH308 — Type K handheld dual-input thermometer

A free 1 m (40') Type K insulated beaded-wire thermocouple with subminiature connector and wire spool caddy is included (one per channel). For applications requiring documented traceability, NIST-traceable calibration with points is available as CAL-3-HH.