Wireless Temperature Transmitters – Benefits and Drawbacks
What is a wireless temperature transmitter?
First, let’s define what a temperature transmitter (TT) is in general. A TT is a device that both measures the temperature of something, like a room, and transmits the signal to another location to be use to control a piece of equipment or to record the temperature of something. A classic example is to control the flow of heating or cooling for a room using a thermostat. Traditionally these devices sent, or transmitted, their signals over wired connections, but this isn’t always the case these days.
Wireless temperature transmitters have been around for a number of years and are used for various purposes including home thermostats, as part of heating and cooling systems for commercial buildings, and in industrial applications to measure process temperatures such as at refineries and chemical plants.
Parts Associated With A Wireless TT
These devices have a couple of main components, a transmitter and a receiver. The transmitter is the part that senses the temperature and sends that signal to the receiver. You can see an example of a wireless transmitter in the picture above. This style has the sensor, or temperature probe, attached to the transmitter by a cable so it can be mounted somewhere near the transmitter but not in the exact same location. This one has a 25 foot cable, so that is the limit on how far away the sensor can be from the transmitter. The transmitter will interpret, or make sense of, the signal the probe senses and then transmitt that signal to the receiver.
The receiver is the device that is located in another area and that receives the wireless signal from the transmitter. The receiver isn’t shown in the above picture, so I’ve included the below sketch to show the components.
Some transmitters have an onboard display so you can see the temperature locally on the transmitter without having to go and look at the receiver. This is useful in the case where you need to visually monitor something is at the right temperature while working local to the TT and also record that temperature remotely by sending a wireless signal to the receiver. For instance, if you’re working on a chemical process.
Say you are in a room charging chemicals into a tank and need to know if the reaction is occurring within acceptable temperature limits. You’d want to be able to check the temperature while you’re adding the chemicals and, in some cases, also have records to verify the temperature was within spec. This could be done by recording the data from the receiver by wiring it to a chart recorder, programmable logic controller (PLC) or other recording device.
Wireless TT’s at Home
There are a few good reasons to use wireless TT’s in residential buildings. One is when retrofitting a home with new heating or cooling equipment, such as adding a new section of baseboard heating. There’s a good chance that you would have to cut into a finished wall and/or ceiling to run a new wire to a new TT. This is doable, but may not be ideal. Some houses may be quite old and have decorative or hard to replace plaster, or it may be too inconvenient for a do-it-yourselfer to crawl up into their attic space to run a wire.
Enter the wireless TT. You would just screw the transmitter (thermostat) into the wall where ever makes sense, and have the receiver pick up the transmitter’s signal. The receiver does not get wired to the transmitter but does get wired to a controller or valve or other device to use the transmitter’s signal. In the case of the a thermostat controlling a baseboard heater, you’d likely wire the receiver into a boiler controller (see the figure above). The beauty of this would be the wire only has to go from the receiver to the boiler where you can mount the receiver in the same room as the boiler. Thus eliminating the need to cut holes into the walls or ceiling to run wires.
Wireless TT’s are often battery powered and have a somewhat substantial battery life, including up or even more than a year. For the ease in installing a thermostat by just mounting it on the wall and turning it on to connect to the receiver that is wired locally to the boiler (or air conditioner, etc.), replacing a battery can be a small price in comparison.
Wireless TT’s In Office or Other Commercial Buildings
A similar thought process can be employed when considering the use of wireless temperature transmitters in commercial buildings as for residential. If adding a new TT for a renovation, a wireless one may do the trick. An additional consideration in the commercial environment is the potential increased density of materials of construction. These would be things like block walls and steel doors, basically any construction that may impede the ability of the TT to get the wireless signal to the receiver.
Signals from wireless TT’s must make their way from point A (transmitter) to point B (receiver) through the air. If something in the path of the signal is too dense, the signal may be dropped sporadically or may not be picked up at all. If possible, I would suggest trying the transmitter and receiver in the actual desired location in a commercial application before permanently mounting the associated receiver, although you’ll need to set it up to see if it’s capturing the signal of course.
Security may play a role here, where a wired signal is more secure since its not being transmitted through the air. If you want to ensure your signal is not attenuated (captured) by a device other than your receiver, or if you want to make sure your receiver doesn’t pick up a signal from anything other than your desired TT(‘s), a wired connection is a safer bet.
Wireless TT’s at Refineries and Other Industrial Sites
Refineries are places that process raw materials that have been extracted from the ground, like crude oil or ores like iron. These facilities can be huge, sometimes having miles between structures. Running cables between such expanses is very costly. Historically, refineries have used manual readings to save on capital installation costs. Employees would literally drive from one area to the next, taking and recording critical readings.
As you can Imagine, there are also costs for these manual readings, including continuously paying personnel and purchasing and maintaining vehicles. Using wireless temperature transmitters at these sites can be a great option to save on these recurring, but do have their own installation and maintenance costs.
Chemical, pharmaceutical and other types of industrial plants can have a lot of heavy construction, especially in the processing areas. This can make it tough to transmit a signal from one room to another. Another concern here is the smaller amount of options for wireless explosion proof solutions than wired TT’s. Often times it is necessary to use the wired type of transmitter in these applications.
Wired or Wireless, Which is Better?
There are a few clear advantages of wireless temperature transmitters over wired ones, including less wiring and cutting into existing construction and easier installation. They do have their drawbacks though, like the ability to have signals captured by unintended devices, unintentionally capturing signals or interference from other devices, not being able to pass reliable signals through some types of building materials and less available models that use wireless technology.
In summary, it really depends on the application as to which style of TT is better suited.
I trust this guide sheds some light on what to consider when choosing between a wired or wireless TT. Please let me know if I can help answer any questions by leaving me a comment on this post.
Thanks so much for Reading!