Temperature Humidity Meter with Display: Logging Thermo Hygrometers

A basic digital thermo hygrometer is cheap and useful, but it only tells you what the room is doing right now. It does not know what happened overnight, it cannot call anyone when the air-conditioner trips, and the paper chart someone fills in twice a day is the only record an auditor gets. A logging meter keeps the display and adds the three things a plain meter lacks: a continuous record, an alert when a limit is crossed, and a report that can be defended.

The 50-series loggers are designed as a direct replacement for the wall hygrometer. They mount on the wall, show live readings on the OLED screen, and log in the background at a 15-minute interval by default (configurable). The internal memory holds 90 days of readings at that interval, so a network outage or a standalone installation does not leave a gap in the record.

Each unit carries a 1.3-inch 128 x 64 pixel monochrome OLED display that shows the current temperature and humidity, so the room reading is visible without opening an app. The enclosure is IP64 rated and wall mountable, and the device is plug and play on a 5 V / 1 A DC input. An internal lithium-ion battery keeps the meter reading and logging for up to 20 hours on the connected models and up to 24 hours on the standalone model when mains power fails.

Because the sensor is built into the body, the meter must be mounted in the space it measures. Place it at the height of the stored product or the working area, away from air-conditioning diffusers, doors, windows and heat-generating equipment, so the display reflects what the product actually experiences rather than the air leaving a vent.

The measurement is identical across the range: a built-in sensor reading 0 °C to +50 °C with ±0.5 °C accuracy and 0.1 °C resolution, and 0 to 100 % RH with ±2 % RH accuracy and 0.1 % RH resolution. Choose the model by the network available at the site.

The 0 °C to +50 °C range covers every ambient space a humidity temperature meter is normally used in: medicine stores held below 25 °C, operation theatres at 18 to 24 °C, server rooms, warehouses and offices. ±0.5 °C and ±2 % RH is the accuracy regulators and NABH assessors typically expect from a room monitor, and 0.1 resolution means small drifts show up before they become excursions.

For regulated use, pair the meter with a calibration certificate so the reading is documented as well as recorded. NABL-traceable calibration certificates are available on request. If you need to measure inside a refrigerator, freezer, chamber or oven, the built-in sensor is not the right tool; see the probe-based models below.

The connected models (WTH50, MTH50, ETH50) report to the Ideabytes cloud platform, with web and mobile apps for iOS and Android. Set a high and low limit for temperature and humidity on each meter and the platform raises live alerts and app push notifications, with SMS available, when a limit is crossed. Every alarm is kept in an alarm log with an audit trail, and excursions can be closed with a CAPA entry.

Reports are 21 CFR Part 11 compliant PDFs with trend graphs, mean kinetic temperature (MKT) and the audit trail, generated on demand or on a schedule. The standalone OTH50 produces the same 21 CFR Part 11 PDF reports, MKT, audit trail, alarm logs and trend graphs from its own stored data, without a cloud connection. Software features are provided in different plans; ask Sales for details.

The catalogue lists these meters for pharmaceutical storage monitoring, food safety and cold chain management, laboratory and research environments, industrial process monitoring and healthcare facility compliance. In practice that means retail and hospital pharmacies that must hold stock below 25 °C and 60 % RH, operation theatres and ICUs that need both values logged room by room, server rooms where humidity drives static and condensation risk, and warehouses storing moisture-sensitive goods.

A visible display matters most where people act on the reading: a pharmacist deciding whether to switch on the air-conditioner, a theatre nurse checking the room before the first list, or an IT engineer walking the server room. The logger behind the display then provides the record that paper charts cannot.

When the display must stay outside and only the sensor goes inside, for example in a stability chamber, a walk-in cold room or a fridge, choose a probe-based temperature and humidity data logger instead. The IBI-WTH120, IBI-MTH120 and IBI-ETH120 use an external probe rated from -40 °C to +120 °C with the same 0 to 100 % RH, ±2 % RH humidity specification and the same OLED display on the logger body. The full range, including USB and Bluetooth loggers for shipments, is on the temperature and humidity data logger page.