Temperature Alarms, Wireless Temperature Monitoring, Remote Temperature Monitoring: What does it all mean?!

There are 3 primary levels of temperature measuring systems that have evolved over time: 1) Thermometers 2) Alarms and 3) Monitoring Systems.  We define a 4th level, Remote Temperature Monitoring, and we spend our time designing and thinking about “Level 5.”

Below is some discussion on what each is and what the benefits and drawbacks are for each one. Monitoring systems are the most complex with the widest range of significant features, so I’ll focus most of this post on them.

1) Thermometers

Imagine a good ol’ fashioned mercury-based thermometer. Thermometers can be electronic these days, but the functionality is the same.

The problem with thermometers is that you have to physically go and look at the thermometer to know the temperature, and the only way to have records is to manually record them. This is a laborious process and gets expensive if you have many temperature-sensitive areas that you want to keep an eye on.

2) Temperature Alarm Systems

A traditional alarm system triggers an alarm when the temperature goes outside of a designated range.   Generally this alarm will involve an audible alarm and possibly flashing lights.

There are several problems with these types of systems:

  • Temperature history is not easily accessible or analyzable, or may not be recorded at all.
  • Generally, if an alarm unit is not installed in the equipment by the manufacturer, these alarm systems are “hard-wired”–meaning wires are run to wherever temperature is being monitored, which makes them more expensive to install and limited in how many points can be measured.
  • Usually “trigger” temperatures, the conditions that trigger the alarm, aren’t especially intelligent.  Generally, only a few trigger temperatures are set, and if those temperatures are reached, the alarm is sounded.
  • An alarm is not a targeted form of communication.  Anyone and everyone is subjected to an alarm–potentially even customers in the vicinity. Also, if no one is around to here the alarm, it doesn’t do any good.
  • Alarm systems have no method of “self-diagnosing” problems — which means that if they malfunction, you won’t know about it.  This creates serious vulnerabilities. How do you know it’s working?

Temperature Alarm Systems as a part of Security Systems

There are also temperature alarm systems that are hooked into larger security systems, so if the temperature alarm is triggered, the security company becomes aware and calls whichever point of contact they have on file.  This is certainly a step up from an alarm that only alerts people that are in the vicinity.

3) Electronic Temperature Monitoring Systems

The next evolutionary leap for temperature measuring systems is electronic “monitoring” systems.  These have a few key features:

  • Temperature is measured by electronic temperature sensors (you could think of them as being similar to an electronic thermometer that is capable of transmitting data.)
  • Temperature is measured at defined frequency and is recorded electronically.
  • The temperature records can be turned into reports that can be printed out, emailed to the appropriate individuals, or checked on an electronic dashboard.
  • For any modern electronic temperature monitoring system, targeted and more intelligent alerts can be set that can make use of time variables and trigger temperatures. Generally, these alerts come in the form of text messages, phone calls, or email to designated personnel. For instance, you might set an alert that says, “send my facilities manager a text when the refrigerator goes above 41 degrees for 15 minutes.  And email me so I know it happened as well.”

While most systems share these characteristics, there are some important distinguishing features.

Wired Temperature Monitoring vs Wireless Temperature Monitoring

This is the first major differences between systems.  Wired Temperature Monitoring systems require wires to be run between where the temperature is measured and where the temperature data is stored.  There are several problems with these solutions:

  • Wired temperature monitoring systems are generally much more expensive to install due to the labor involved.
  • Wires generally prohibit highly granular measurements to be taken.  For instance, if you had a large warehouse and you wanted to know the temperature variation throughout by measuring temperature at 16 points throughout the facility, it would be difficult, expensive, and potentially disruptive to install such as system.

However one of the advantages of wired systems is that, so long as the wires aren’t damaged, the temperature measurement data can get from the point of measurement to the data storage unit without interference.  In some environments, only wired systems are suitable.  For instance, a beef distributor was interested in the freshsense monitoring system.  Unfortunately, this beef distributor happened to be located in an old nuclear bomb shelter with walls that were 8 feet of concrete and steel.  A completely wireless system would not have fulfilled their needs.  (But moreover, they actually were in need of a full resource management system–another class of products we can talk about later. We were sad that we could not serve them, but I think we were still helpful).

Wireless temperature monitoring systems get rid of of the wires and make use of wireless sensors that transmit data via wireless methods such as WiFi or radio waves ing and serving data). There are several important benefits of wireless temperature monitoring systems:

  • Installation costs are lower because wires do not need to be run to all the areas where temperature is monitored.
  • More areas can be monitored, since all that is required is placing the sensors.  This way you can get more granular data.
  • Wireless systems are much more mobile.  It shouldn’t be an issue to move the sensors around, although you’ll have to make sure the sensors are still within range of the “reader” where the sensors send their data.

Wireless Communication Methods

It’s worth noting that wireless temperature sensors might use a variety of wireless communication methods to transmit the temperature data.  Some possibilities are WiFi (your wireless internet), GSM (similar to a cell phone connection), or “RF” (similar to what most “EZ Pass” tags use that let you drive through toll booths without having to stop and pay with cash).  The best one depends on the context.  Our favorite is “RF” because of its low power consumption and large transmission range.

Non Web-based Temperature Monitoring vs Web-based Temperature Monitoring

The most import aspect of these two types are who manages the data and how that data is accessed by a user. What I’ve dubbed a “Non Web-based Monitoring System”, refers to a type of system that would require you to buy computers that would store your temperature data.  Here’s the problem with this type of system:

  • You need your own IT specialists to manage your computers and the software involved with the system.

This creates significant overhead.  Accessing the data might also require you to be on the “local network” which can create all sorts of headaches.

Web-based temperature monitoring systems are a fairly recent phenomenon that became more prevalent when the internet became faster and more widespread. Another important driver of web-based temperature monitoring systems was what people often refer to as “cloud computing.”  Here are the key features of  web-based temperature monitoring sytems.

  • The temperature monitoring data and software live on a server that is out “in the cloud.” This is a somewhat funny way to say that your software and data are on a server (a computer) that is accessible over the internet.  Addtionally this server is physically located in a facility with many other servers and a group of specialists that know how to take good care of computers.
  • You don’t need your own IT people to take care of the computers and the software.
  • You can access your data and set your alerts by simply logging into a website with a username and password. Moreover, you can do this from anywhere in the world with any device that has an internet connection.  You could check on your refrigeration temperatures on the beach with your iPad! (Now that’s living right!)
  • Software features are instantly made available.  When your service provider updates the data management software (let’s say they created a snazzy new report), as soon as the feature is ready, they deploy it, and it becomes available to you the very next time you log in.  At FreshTemp, we’re constantly making improvements to our Online Dashboard. Since it’s a web-based application, you get to enjoy those improvements without doing a thing.

Self-Diagnostics and System Alerting

I think this is a very important feature that most modern systems are starting to catch on to.  If you’re counting on your temperature monitoring system, you have to be able to rely on it and trust it. However with any system, especially systems that involve sensor networks, there is a chance that part of the system might fail.

Self-diagnostics answers the question, “is it working?” Essentially, a self-diagnosing system is aware of how well it’s working.  For instance, what happens if a forklift unknowingly smashes into a sensor? A self-diagnosing system would say, “wait a minute, something is fishy here, I haven’t heard from little Tommy Sensor in a while, something must be wrong.  I better alert someone!”  This is an important feature.  Yes, things go wrong even for the best, but if you know about it, appropriate steps can be taken.

4) Remote Temperature Monitoring


Remote temperature monitoring is the term we use to describe a specific type of system (like our freshsense monitoring sytem).  You would be right to consider it a type of wireless electronic temperature monitoring system, but this is the nature of the evolving world of technology products: advancements are made possible by their precursors.  Wireless temperature monitoring is a very broad class, and we think the technological advancements and configuration of features makes it deserving of a whole new level.  Remote temperature monitoring systems:

  • use inexpensive wireless temperature sensors (wireless devices have a come a long way in the last 5 years) that allow you to measure a lot of data points if you want to
  • is web-based, so you don’t have to spend time messing with software updates and computer crashes or worrying about losing your data.
  • have data accessible through a website, as well as the ability to configure alerts through the website.
  • are “real-time”–this means that the current temperature reading that you can see on the website reflects the current temperature where the sensor is sitting.  It doesn’t take 30 minutes (or even 5 minutes) for the sensor’s measurements to make it to the website’s reports.  (Okay, I have to brag here because I think it’s cool, on the FreshTemp Online Dashboard you can actually switch to a mode that allows you to actually see the data points pop up on a graph as they’re measured by the sensor.  This way you can see which way the temperature is trending.)
  • are self-diagnosing so you know when there is a problem.
  • are extensible, so you can add other temperature measurement devices (like our null) besides stationary temperature sensors to the system so all your data can be held in one place.

It’s worth noting that, even if a system has all these features, the performance can very a lot.  For instance, some temperature sensors only take a temperature measurement once every 10 minutes and have a battery life of less than a year.  Others can take a temperature measurement every 30 seconds and still last multiple years.

The Level 5 Temperature Monitoring System

You might think the evolution of temperature monitoring systems would stop here where most of the obvious problems have been solved. But, there’s a huge leap coming.  We’ll talk about this soon.  But for today, we just wanted to discuss what some of the key features and distinctions are that you might encounter as you attempt to navigate the maze of temperature monitoring.  Let us know if you have any questions! Just send a line to [email protected]