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Compact Portable USB Data Loggers

Portable Temperature Data Loggers

$132.20

Item# OM-91

Volume discounts available
Volume Discount Schedule
Quantity Price each
1-4 $132.20
5-9 $125.59
10-24 $122.95
25-49 $117.66
50-99 $115.01
100+ $112.37

In stock

Lead Time (If not in stock): 5 weeks
Portable Temperature Data Loggers OM-91 OM-91
  • Models for Temperature (OM-91) and Temperature/Humidity (OM-92)
  • Immediate, Delayed (Specific Date/Time) or Pushbutton Start
  • Real-Time Mode
  • User-Configurable High and Low Alarms

OM-91 Model Options

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Edit these specs to order a different model. Not all combinations are valid. Options compatible with previous selections will be in bold.

*Highlighted options are not compatible. Please select a different combination.

Measurement Type
Number of Measurements
Additional Feature
Input Type
Maximum Samples
Power
Data Interface
Max Sampling Rate


The OM-90 Series are portable, battery operated, temperature (OM-91) and temperature/humidity (OM-92) data loggers. The OM-90 Series data loggers offer accurate and repeatable logging for temperature and relative humidity. Temperature is measured to an accuracy of ±0.3°C over the range of 5 to 60°C (41 to 140°F) and ±2.0°C over the full range of -30 to 80°C (-22 to 176°F). Relative humidity is measured to an accuracy of ±3.0% RH over the 20 to 80% RH range and ±5.0% RH over the 0 to 100% RH range. Both temperature and relative humidity are logged at a user configurable logging rate which is software selectable.

These data loggers are ideal for transportation applications where it is necessary to document that the material in-transit has stayed within particular environmental limits. High/low alarm limits can be set above or below which LED indicators will be activated so that the user can become aware that the desired transportation conditions have been exceeded.

Each data logger can be assigned a 16 character name. This can be helpful in applications where multiple data loggers are used and there is a need to distinguish between them (for example based on location).

The data logger includes a very easy to use software application. The application is used for configuration of the logger, extraction of logger data, graphically viewing data, spread sheet analysis of data and saving data to file (typically in comma separated value CSV file format) for third party applications such as Microsoft Excel. The graphical user interface is completely intuitive in terms of configuring new devices and extracting data from a field device. When the user has multiple devices requiring the same setup then a logger setup from a saved configuration file can be preloaded into the application to help expedite the process and ensure all loggers get setup identically. The application does not require any driver installations to connect to the data logger. Just install the software, run it and then connect the data logger.

SPECIFICATIONS
Temperature
    Range: -30 to 80°C (-22 to 176°F)
    Resolution: 0.01°C
    Accuracy: ±0.3°C from 5 to 60°C (41 to 140°F)
    Calibration Accuracy @ 25°C ±20°C: ±0.1°C
Humidity (OM-92 Only)
    Range: 0 to 95% RH
    Resolution: 0.01% RH
    Accuracy: ±3% over 20 to 80% RH range; ±5% RH below 20% RH or above 80% RH
    Calibration Accuracy @ 25% RH: ±1.8% RH @ 25% RH
Memory
    OM-91: 65,520 temperature measurements
    OM-92: 65,520 temperature and 65,520 humidity measurements
Start Modes: Immediate start on disconnect from PC, delayed start (scheduled date/time) or pushbutton start
Recording Mode: Stop on memory full; when data logger operation is start/stopped by user intervention via button press, last memory location is retained
Recording Interval: 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)
Real Time Logging: Displays real time data when connected to a PC
Real Time Clock: Time automatically synced to PC
Battery Backup: Continues to keep time when off
Accuracy: 0.50 sec/day (~3 min/year)
Alarms: High and Low alarms for temperature and humidity; dedicated alarm LED indicator
LED Indicators: Alarm and status LEDs
Device ID: Each data logger can have a 16 character name assigned
Connections: USB-C port
Power: 3V lithium CR2450 battery included (user replaceable)
Battery Life: Over 4 year battery life while logging
Bypass Mode: Unit is powered from USB when connected to conserve the battery
Dimensions: 53 H x 33 W x 15 mm D (1.38 x 2.36 x 0.6')
Weight: 25 g (0.9 oz)
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Rated 5 out of 5 by 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 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 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 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 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 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 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 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
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Are these NIST recognized calibrated? Can they be calibrated on a routine basis?

Asked by: Kurt1234
Hello Kurt Yes they can be NIST calibrated, the part number would be OM-92-NIST. We do recommend them to be calibrated at least once a year, depending on usage.
Answered by: JA Engineer
Date published: 2020-04-06

After installing the software for OM-92 from Omega website trying to run I come up w/ MSVCP100.DLL "not found" !?!

Asked by: BrunoJr
Thank you for your question. We will require more information to help on this question, please email the DAS team at DAS@OMEGA.COM
Answered by: Application Engineer PV
Date published: 2023-09-05

What is the latest version of the firmware?

Asked by: panosh
Thank you for your question. Please e-mail your questions to DAS Engr-DAS@OMEGA.COM
Answered by: Eagle
Date published: 2020-07-25

I have a 120 day shipping that I would like to use on Logger Is it possible to calibrate the logger (OM-92) to measure temperature and humidity once every 4 hours? Does it have enough memory to keep a record of the delivery time ?

Asked by: yoni
Thank you for your question. The longest duration for logging interval is 1 hr and 4 hrs is not possible. The memory is :OM-92: 65,520 temperature and 65,520 humidity measurements
Answered by: Application Engineer PV
Date published: 2022-11-07

Do you have an sdk to integrate the sensor in a bigger system ? There is a way to communicate in serial directly to sensor without using the software ?

Asked by: huotj
Thank you for your question. Unfortunately, there is no other way to communicate with logger other than the provided software.
Answered by: Bald Eagle
Date published: 2020-09-03

Can these be used inside of HVAC Ductwork? 

Asked by: Spiez
Thank you for your question. Yes, as long as it is in a non-condensing environment and free of any particles that can damage the sensor.
Answered by: Application Engineer PV
Date published: 2021-07-21

Do these come NIST calibrated upon purchase, do they come with a certificate?

Asked by: chris2299
Hello Chris Regarding your question, yes the -NIST versions are calibrated and they do include a certificate as well.
Answered by: JA Engineer
Date published: 2020-08-25

Can these loggers be sent back periodically for recalibration?

Asked by: APDE
Thank you for your question. Unfortunately, the loggers cannot be sent back for periodic calibration.
Answered by: Application Engineer PV
Date published: 2021-09-30

Who is Senonics Minnow?

Asked by: panosh
Thank you for your question. Please e-mail your questions to DAS Engr-DAS@OMEGA.COM
Answered by: Eagle
Date published: 2020-07-25

Is it possible to put OM-92 into an oven set at 60°C and at 145mbar for 30h?

Asked by: Christophe
Thank you for your question. We will require more information to help on this question, please email the DAS team at DAS@OMEGA.COM
Answered by: Application Engineer PV
Date published: 2023-02-21

Can I use the OM-92 inside of a walk-in mechanical convection oven, running at 60°C, anywhere from 2-4 months? It is an aging study oven, and we wish to capture humidity data that we can download after a 2-4 month cycle.

Asked by: Mvasquez
Thank you for your question. The application should be ok just note accuracy specs on data sheet.
Answered by: Raptor
Date published: 2020-08-08

What is the recommended NIST calibration interval for the OM-92?

Asked by: Maine Jason
Thank you for your question. There is none. Because it is not cost-effective for re-calibration so we recommend purchasing a new unit if you feel unit is out of calibration.
Answered by: Application Engineer PV
Date published: 2022-12-03

What are the CHECKSUM values of the various ZIPped files and why are they available from so many different locations, including unsecured FTP sites?

Asked by: panosh
Thank you for your question. Please e-mail your questions to DAS Engr-DAS@OMEGA.COM
Answered by: Eagle
Date published: 2020-07-25

The manual says the unit will shut down if the memory gets full but there's no indicator of remaining memory and no menu item in the program for clearing the stored data. How is this done?

Asked by: Calguy
Hello, thank you for your question. The memory is erased automatically every time you start a new logging session.
Answered by: Engineer DA
Date published: 2024-01-10

Would these be appropriate for use in a humid environment like a greenhouse?

Asked by: Liam1234
It will have to be an environment with dry humidity, if the humidity is condensing or developing moisture it can cause issues with the internal sensor.
Answered by: JA Engineer
Date published: 2022-07-28
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