Header image strip
Banner image displaying our Wireless SAW Temperature Sensor systems used for Electric Power Grid and Culinary applications
Home > Products > Temperature Sensors
Click this Assistance button for help with any of your questions

Wireless SAW Temperature Sensor System

SenGenuity's Wireless SAW Temperature Sensor Systems are based on the technology of Surface Acoustic Waves and give customers an edge at manifold applications where wireless and batteryless temperature measurement is required.

Image of an electric power grid system where our temperature sensor would provide a solution
Wireless SAW Temperature Sensor System Overview
SenGenuity offers a passive (no batteries and no energy harvesting), wirelessly interrogated, SAW based temperature measurement system that is ideally suited for wide range of applications. These include high power switchgear, rotating machine components and wireless food probes; basically, any application that requires an electrically non-invasive solution, where access is limited or maintenance is difficult or impossible.

Elements

The SAW Temperature Sensor System consists of the following crucial elements:

Sensor System Elements

Functionality

  1. Wireless Reader (Interrogator) generates a RF Signal (limited bandwidth) and transmits it by the Reader Antenna
  2. Sensor Module Antenna receives the RF Signal and converts it into a Surface Acoustic Wave (SAW) inside the piezoelectric Sensor Element
  3. acoustic energy stored in the SAW Sensor Element is transmitted via the Sensor Module Antenna back to the Reader with a temperature dependent frequency
  4. This temperature dependent frequency received by the Reader Antenna is indicative of the measured temperature at the Sensor Element. The temperature information is transmitted via the requested interface to the PC/PLC
Wireless SAW Temperature Sensing System Diagram

Advantages

The SAW Technology used by SenGenuity offers some exceptional advantages to conventional temperature measurement systems. The sensor are:
  • Passive (No Batteries, No Energy Harvesting)
  • Electrically Non-Invasive
  • Low Cost
  • Small in Size
Additionally, SenGenuity's temperature sensors demonstrate exceptional performance stability characteristics, meeting DIN IEC 68 T2–27 specifications for shock rating and DIN IEC 68 T2–6 standards for vibration. Temperature stability characteristics are assured by DIN IEC 68 Part 2–14 Test N standards.

Key Features

The key attributes of the Surface Acoustic Wave System are:
  • 3 antenna ports enabling interrogation of up to 32 sensors
  • Wireless SAW based temperature sensors
  • Passive (no batteries, no energy harvesting)
  • Multi–Communication protocol: RS485, RS232; Analog–Output; Modbus; CAN; USB
  • Sensor temperature Range: –20°C to 120°C
  • RF operating range: 428MHz to 439MHz
  • System accuracy: ±2°C
  • Control room software with alarm capability
  • Enhanced operator and asset safety
  • Environmentally friendly
  • Real–time monitoring and data logging
  • Monitor inaccessible locations
  • Reading distance up to 3 meters1
Configurations

SenGenuity offers the customer
  • Scalable System Configuration:
    • 6 Sensor System
    • 12 Sensor System
    • Several different interfaces (eg. USB, RS232, RS485)
  • Customized Sensor Module Configuration2
  • Support and Adjustment of Software2



1 Depending on RF environment and antenna
2 Customization upon request. Not all requests can be implemented. Customization is at the expense of the customer
Image of an electric power grid system where our temperature sensor would provide a solution
Wireless SAW Temperature Sensor System for Switchgear Measurement
Switchgear, which serve as important points of control within power distribution systems, transformers and other transmission and distribution components, are susceptible to failure if not closely monitored and controlled. Increased loads and often outdated equipment can greatly stress switchgears. The resulting increases in temperature and wear out of critical switchgear components can cause significant degradation of metal contacts and insulation. In turn, this increases the probability of internal short–circuits or increases the contact resistance, which, if unchecked can lead to catastrophic system failure and personal harm to system operators. Conventional methods are often expensive, providing only sporadic coverage or a snapshot of conditions which is not entirely effective. Furthermore, they often require human resources – raising reasonable safety concerns, regular maintenance and are not as accurate.

SenGenuity provides a broad portfolio of sensors and components to easy and cost effective monitor switchgears continuously and with little to no maintenance.

SenGenuity's passive, wireless temperature Sensor Modules enable the temperature measurement directly at suspected hotspots within the switchgear, indicating the condition of the system continuously online. Furthermore, the system can now be enhanced with a Partial Discharge (PD) Functionality to detect insulation breakdown issues. Since the systems condition is also impacted by the direct environment, SenGenuity can also offer a Humidity Sensor Reader (HSR–01) to measure relative humidity and ambient temperatures.


Wireless Sensor Reader WSR–T2

The Wireless Sensor Reader WSR–T2 is the electronic Reader unit required for interrogating SenGenuity's passive and wireless Sensor Modules as well as using the Partial Discharge (PD) functionality.

Wireless & Passive Sensor Modules

SenGenuity's wireless and passive Sensor Modules are ideally suited for switchgear applications to monitor the temperature of current bus bars, breakers and other suspected hot spots. Due to their passive nature – no batteries, no cables – there is no risk of creating flash overs inside a cabinet.

The Standard Switchgear Sensor Modules are available both as 6 Sensor and 12 Sensor System.
Bolt Mount with Hole 2
Photo of the Bolt Mount with Hole 2 sensor
6 SM Datasheet
12 SM Datasheet
Universal Mount 2
Photo of the Universal Mount 2 sensor
6 SM Datasheet
12 SM Datasheet
Universal Mount 3
Photo of the Universal Mount 3 sensor
6 SM Datasheet
12 SM Datasheet
Customized Sensor Modules maybe required depending on specific application and can be designed within SenGenuity thanks to the broad knowledge and having all expertise available in house.


TempTrackr® Starter Kits

A good option for testing the functionality and application of the 6 Sensor System offers the Starter Kit consisting of 6 Sensor Modules with three different mounting versions, three different Antennas, and one WSR–T2 Reader. All compiled for easy plug–and–play testing.

Wireless SAW Temperature 6 Sensor System Kit Datasheet:

WSR–T2 Reader Antennas

Every WSR–T2 Reader comes with three SMA connectors for Antennas. SenGenuity has developed some Planar Inverted F–Shape Antennas (PIFA's) that are ideally geared to the Sensor Modules. Additional, these Antennas are perfectly suited to simultaneously use the Partial Discharge (PD) Functionality.

Wireless SAW Reader Antenna Datasheet:

Partial Discharge Functionality

For an even more comprehensive monitoring system of switchgear cabinets, SenGenuity has added the Partials Discharge (PD) Functionality to its WSR–T2. This integrated functionality requires no further hardware and uses a highly efficient real–term algorithm along with a Reader Antenna to analyze signal patterns and report partial discharges.

Related Application Note:

Humidity Sensor Reader HSR–01

Since humidity has a big influence on partial discharge and system aging, our Humidity Sensor Reader HSR–01 is a perfect supplement for the switchgear monitoring system.

The HSR–01 can be operated both, as a stand–alone sensor for relative humidity and ambient temperature or connected via RS485 interface to the WSR–T2.

Humidity Sensor Reader HSR–01 Datasheet
Humidity Sensor Reader

Image of a Culinary application where the SenGenuity Wireless Food probe would be used as a solution
Wireless SAW Temperature Sensor System for Food Probe Measurement
Conventional, wired food probes greatly reduce the overall burden of monitoring food temperatures. By providing an embedded solution, wired food probes eliminate the need to have external gadgets to monitor food temperature. However, the wire that links the probe to the oven has disadvantages associated with it: Photo of the SenGenuity Wireless Food Probes and interrogation unit which monitors temperature wirelessly and batterylessly
  • The wire can cause injury when hot, so the user has to be extra cautious while handling.
  • The wire can either be too long or too short.
  • If too long, it has to be coiled up and neatly arranged within the oven cavity.
  • If too short the probe can only be inserted at certain angles causing the user to potentially struggle with the placement of the food within the oven cavity.
  • Cleaning the wired food probe can be difficult and unwieldy. This can greatly discourage use of the probe.
  • Wires are likely to be damaged, which increases maintenance costs.


However, today the technology to make the food probe completely wireless and batteryless exists. Surface Acoustic Wave (SAW) Technology allows passively powered sensors to be wirelessly interrogated to obtain temperature measurements. Using this technology, many of the before mentioned disadvantages with wired food probes are completely eliminated:
  • The shape of the wireless food probe enables an easy handling and removal even when hot.
  • There is no need to worry about wire length as the probe is wirelessly linked to the oven.
  • The wireless food probe, just as any other utensil, can be easily cleaned as it is dishwasher-safe.
  • Ease of use
  • Reduce the maintenance cost due to absence of the wires and batteries.
Wireless SAW Temperature Sensor System for Food Probe Datasheet: Related White Paper and Application Notes: Wireless SAW Reader Datasheet: