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OM-90-Series
Compact Portable USB Data Loggers
Models In Stock
- Measures temperature (-20 to 75°C) and humidity (0–100% RH) with high accuracy.
- Real-time mode displays live readings for instant monitoring.
- User-configurable high/low alarms with LED indicators for immediate alerts.
- USB-C interface with free software for easy data transfer and analysis.
OM-90-Series
From
C$
207.86
Models In Stock

Product Overview
- Alarm Note High and Low alarms for temperature and humidity; dedicated alarm LED indicator
- Battery life up to 4 yr
- Battery Size and Type CR2450, 3V Li-ion
- Electrical Connection USB Micro-B Female
- Form factor Handheld
- Height 15 mm
- LED Indicators Alarm and status LEDs
- Length 53 mm
- Memory 65520
- Operating Time Time automatically synced to PC
- Samples,Max 65000
- Sampling Rate 1 Hz (1 update/second)
- Sampling Rate Note 1 sec, 10 sec, 30 sec, 1 min, 10 min, 30 min, 1 hr (software selectable)
- Software Compatibility Windows XP/Vista/7, 8 & 10 (32-bit and 64-bit)
- Start Modes Adjustable Delay Start, Immediate Start, Push-button
- Supply Power Type Battery
- Temperature Accuracy Note ± 0.3°C from 5 to 60°C (41 to 140°F), Calibration Accuracy @ 25°C ± 20°C: ± 0.1°C
- Temperature Measurement, Max 80 °C
- Temperature Measurement, Min -30 °C
- Temperature Resolution 0.01 °C
- Time Accuracy 0.50 sec/day
- Weight 25 g
- Width 33 mm
The DwyerOmega OM-90 Series is a compact, portable USB data logger designed for reliable monitoring of temperature and humidity in transport, storage, and environment-sensitive applications. With small form factor and battery power, it offers the ability to log conditions in-transit or onsite without bulky instrumentation or constant supervision.
Built to be simple yet precise, the OM-90 devices measure temperature from -30 °C to +80 °C (-22 °F to 176 °F) and relative humidity from 0-100 % RH, with higher accuracy in most critical ranges. When paired with the free USB-based software, users can configure logging intervals, download data directly, and quickly export files for reporting and trend analysis.
This logger series includes high/low alarm indicators (via LEDs) to alert immediately when readings stray outside acceptable thresholds—a must for applications like vaccine transport, perishable food shipments, museum or archival item storage, and anywhere strict environmental control is needed.
Key strengths of the OM-90 include long battery life (up to 4 years in typical conditions), a clear interface, versatility in starting modes (delay, immediate, push-button), and very user-friendly software that requires no special drivers. Whether you’re monitoring cold chain compliance, conducting field studies, or managing asset condition in remote locations, the OM-90 Series delivers dependable data tracking with minimal fuss.
PDFs & Manuals
Software & Drivers
Show Ratings & Reviews
Rated 5 out of
5
by
Oenophile from
Stupidly simple to use
Bought this to monitor T and humidity in my basement for suitability of wine storage. Very easy to use, super simple, data output is straight forward and versatile. Easy-peasy
Date published: 2016-09-10
Rated 4 out of
5
by
carbonell from
Little bit usefull
This instrument works very fine. Data acquisition using this instrument if great.
Date published: 2017-12-18
Rated 5 out of
5
by
MagicsPawn from
Compact - Easy to Use
The mini CD that came with the product did not work. However, one call to Omega and tech support emailed me the software. Once installed, the setup was incredibility easy. I set the unit up, shipped it to my customer with instructions to install and to hit the small button on the right of unit to activate. 2 weeks later picked the unit up. Downloading the data and transferring to Excel was seamless. Highly recommend.
Date published: 2016-08-25
Rated 5 out of
5
by
TomC from
Works Perfect!
I purchased 2 of these about 2 months ago and they work great. I needed them to monitor temps in 2 tenant spaces.I have been using temp scribes from Grainger in the past and they are a few hundreds each. then you have to purchase chart paper and replace pencils. These are digital and can create a professional looking report to share with others if needed. For the price you can't beat them.
Date published: 2016-07-29
Rated 1 out of
5
by
The Admiral from
Can't really comment
The data logger came with a tiny CD which as everyone knows, almost no computers anywhere have a drive anymore. Went to the website to find file which was extremely difficult and once found, unable to load onto the chrome. So cant comment on items functionality cause I can not get it to work. What can be said, it thank goodness I only bought one and it was only 60 bucks!
Date published: 2016-10-31
Rated 4 out of
5
by
Eric7383 from
Great product when you can find the software
I have had this about 45 days and it has preformed well. DO NOT lose the software disk that the product comes with. You will NEVER find the software on the omega site if you need to download it again
Date published: 2016-09-02
Rated 1 out of
5
by
longtimeuser from
Impossible to use.
Cannot download data from unit to software. Unit will not consistently connect. Software will not work with Windows 10.
Date published: 2016-09-01
Rated 5 out of
5
by
Leonel G from
Easy to use and configure
Acurate and easy to use temperature logger; app and set up easy and simple to use
Date published: 2024-04-21
Are these or any other temp/RH loggers waterproof?
Thank you for your question. Unfortunately, OM-92 or any other TEMP/RH logger we carry is waterproof.
Date published: 2021-03-02
Why even after i change the default directory the application always opens this directory: Local Disk (C) > Program Files(x86)> Omega PC Application > ?
Thank you for your question. Please send your question to DAS Engineering -DAS@OMEGA.COM
Date published: 2020-07-25
Is the OM-92 RoHS compliant?
The RoHS2 status of this part number has not yet been determined.
OMEGA is diligently working to determine the RoHS2 status of this product, but we are still waiting to receive information from our suppliers. The status of this product may change in the near future so please check back soon.
Thank you.
Date published: 2019-07-11
- lead time? - How do we read the measurement on a automation plc (analog signal 0-10V or 0-20mA or 4-20mA etc...) or is it direct modbus serial or tcp connection or other? - How often does it need calibration? - what is the life span?
Hello Marcio
This device strictly works via USB on its own proprietary software, it does not have tcp or modbus capability.
Date published: 2019-09-25
I have an OM-92 and for some reason I'm not getting similar RH values to my standard. Why is this? Specifications say that the accuracy is 3% from 20-80%.
Thank you for your question. We will require more information to help on this question, please email the DAS team at DAS@dwyeromega.com
Date published: 2025-01-09
Good Afternoon, We would like to know if the Compact Portable USB Temperature and Humidity Data Loggers has internet access and if so, what kind of security protocol is in place? Thank you.
Thank you for your question. Unfortunately, the loggers do not have internet access.
Date published: 2022-06-14
How come the software version downloaded is 1.2.3 but as soon as it is installed it says 1.2.19 is available and needs to be downloaded?
Thank you for your question. Please e-mail your questions to DAS Engr-DAS@OMEGA.COM
Date published: 2020-07-25
Would this model be compatible in an environment with significant particulate concentrations?
Thank you for your question. The Om-92 logger as well as all of our Temp/Rh loggers would not work well in this environment.
Date published: 2020-11-20