Skip to search Skip to main content Skip to navigation

Need assistance? Call us: 1-800-663-4209

We noticed you are in , please visit your local site by clicking the below link for regional offers and support.

HH300-303

2 Channel Handheld Type K and J Thermocouple Datalogger USB

Models In Stock
  • Dual Input
  • Dual Display
  • 4 digit LCD
  • MAX, AVG, MIN, HOLD, REL Function
HH300-303
From $ 273.82
Models In Stock
2 Channel Handheld Type K and J Thermocouple Datalogger USB HH300-303 HH300-303
loading all models
Product Overview
  • Additional Features 1 MIN/MAX/AVG/REL/HOLD Functions , Auto Power-Off
  • Battery life 120 hr
  • Battery Size and Type Alkaline 9V
  • Data Interface USB, RS232
  • Display Type LCD
  • Display Type Note 4-digit LCD
  • Height 30 mm
  • Input Protection Voltage 60Vdc/24Vrms
  • Length 184 mm
  • Measurement Type Temperature
  • Number of Measurements 2
  • Operating Temperature, Max 40 °C
  • Operating Temperature, Min 0 °C
  • Relative Humidity, Max <80%
  • Series ID HH300-303
  • Storage Temperature, Max 60 °C
  • Storage Temperature, Min -10 °C
  • Supply Power Type Battery
  • Temperature Accuracy ± 0.7 °C
  • Temperature Accuracy Note 0.1% rdg + 0.7°C (1.4°F)
  • Temperature Measurement, Max 1370 °C
  • Temperature Measurement, Min -200 °C
  • Temperature Resolution ± 0.1 °C
  • Temperature Resolution Note 0.1°C/0.1°F up to 599.9°C/999.9°F
  • Temperature Sensor Type Thermocouple
  • Weight 200 g
  • Width 64 mm

Supported Applications

The HH303 is a low-cost, pocket-sized handheld thermometer built around Type J/K thermocouple inputs, giving technicians a portable, high-accuracy way to measure temperature almost anywhere. A 4-digit LCD shows readings in Celsius or Fahrenheit at the press of a button, and the dual-input design supports a T1-T2 differential display for comparing two points directly.

Standard features such as min/max and average readings, reading hold, and a relative mode make it well suited to HVAC service, laboratory and QA work, food and equipment monitoring, and general field troubleshooting. Each unit ships complete with a beaded-wire Type K thermocouple (one per input), a 9V battery, an operator's manual, and a NIST certificate (no points).

What sets the HH303 apart in the HH300 family is data connectivity: it offers a USB or RS232 interface option so measurements can be logged and read on a PC, turning a simple handheld into a datalogging tool for trend capture and record-keeping.

Operating Conditions & Performance

The HH303 measures across a wide thermocouple range and updates the display quickly. Key performance figures include:

  • Type K range: -200 to 1370°C (-328 to 2498°F)
  • Type J range: -200 to 760°C (-328 to 1400°F)
  • Accuracy: 0.1% rdg + 0.7°C (1.4°F)
  • Resolution: 0.1°C/0.1°F up to 599.9°C/999.9°F
  • Input protection: 60 Vdc or 24 Vrms AC maximum

For T1-T2 differential measurement, accuracy is ±(0.2% T1-T2 reading + 1.7°C) or ±(0.2% T1-T2 reading + 3.4°F); note that the basic accuracy specification does not include probe error. The meter runs on a 9V battery (MN 1604) for up to 120 hour with alkaline cells, operates from 0 to 40°C (32 to 104°F) at <80% RH, and stores from -10 to 60°C (14 to 140°F). It weighs approximately 200 g (7 oz), measures 184 H x 64 W x 30 mm D (7.5 x 2.5 x 1.2"), is CE marked, and carries a 1 YEAR WARRANTY.

Configuration Options

The HH303 accepts both Type K and Type J thermocouples on each channel, and the measuring capability changes with the type selected — Type K reaches -200 to 1370°C (-328 to 2498°F), while Type J spans -200 to 760°C (-328 to 1400°F). Both retain the same 0.1% rdg + 0.7°C (1.4°F) accuracy and 0.1°C/0.1°F resolution.

Beyond the meter itself, capability is extended through interface and power options. PC connectivity can be configured as an RS232 link (software and cable) or as a USB link (software driver and cable), and continuous bench use is supported by an optional AC adaptor. Spare RS232 and USB interface cables are also available so a single HH303 can be adapted to different logging setups.

Key Product Differences

The series centers on one meter with a set of matching interface and service options:

  • HH303 — Type J/K handheld 0.1°C/F thermometer
  • HH310-SW — Software and RS232 interface cable for HH303
  • HH300-SW-USB — Software driver and USB interface cable for HH303 (requires HH310-SW)
  • HH300-ADAPTER — AC adaptor for HH303
  • HH300-CABLE — Spare RS232 interface cable for HH303
  • HH300-CABLE-USB — Spare USB interface cable for HH303
  • CAL-3-HH — NIST-traceable calibration, with points

A free Type K insulated beaded-wire thermocouple with subminiature connector and wire spool caddy is included (one per channel); spares can be ordered as model SC-GG-K-30-36.

Rated 2 out of 5 by from Temperature logger needs working app for Win10 The HH303 temperature data logger is an acceptable device, but it lacks a functional computer application that works on WIN10. I had to write my own using VB. I then added communication capability for HH378. I don't know why OMEGA can't write one app to rule them all.
Date published: 2021-03-26
  • y_2026, m_7, d_28, h_9
  • bvseo_bulk, prod_bvrr, vn_bulk_3.0.48
  • cp_1, bvpage1
  • co_hasreviews, tv_0, tr_1
  • loc_en_US, sid_HH303, prod, sort_[SortEntry(order=HELPFULNESS, direction=DESCENDING), SortEntry(order=POSITIVE_FEEDBACK, direction=DESCENDING), SortEntry(order=SUBMISSION_TIME, direction=DESCENDING)]
  • clientName_omega
  • bvseo_sdk, java_sdk, bvseo-4.0.0
  • CLOUD, getReviews, 7ms
  • REVIEWS, PRODUCT

I am looking for a temperature indicator that gives an indication once the reading settles down (steady state). Imagine a body temperature thermometer that indicates once the temperature stops rising. Can you suggest a model

Asked by: SanjayV
The Thermometers Omega sells will sample and display at a preset rate and do so continuously. On most meters there is a max., min. and avg. function that may provide a good record of how the temperature acted over a measurement period which may be helpful.
Answered by: ApplicationEngineerANB
Date published: 2020-04-22
  • y_2026, m_7, d_29, h_9CST
  • bvseo_bulk, prod_bvqa, vn_bulk_3.0.48
  • cp_1, bvpage1
  • co_hasquestionsanswers, tq_1
  • loc_en_US, sid_HH303, prod, sort_[SortEntry(order=NUM_ANSWERS, direction=DESCENDING)]
  • clientName_omega
  • bvseo_sdk, java_sdk, bvseo-4.0.0
  • CLOUD, getContent, 12ms
  • QUESTIONS, PRODUCT
en-US
en
Save Configuration