Electro-chemicals Protect the Reliability and Performance of IoT Connectivity

By Jade Bridges, Technical Manager at Electrolube (A division of MacDermid Alpha Electronics Solutions)

IoT, otherwise known as the Internet of Things, is a platform enabling embedded devices connected to the internet, to collect and exchange data with each other. Devices can begin to interact and work with each other, even learning from each other’s experience as humans do. The potential for the IoT and connectivity is endless, as everyday objects can connect and share intelligence and knowledge. Some current examples deploying IoT include one of the earliest examples of this technology, wearable technology, which has now extended vastly to encompass the healthcare sector, sports, athletics and even implantables. Some other areas where IoT applications are experiencing rapid growth include the Smart Home, Health Care, Smart Cities, Smart Grids, Agriculture, connectivity within vehicles and Industrial Automation. 

The rapid rise of the IoT revolution is leveraging sensor usage to a whole new level. Sensors are devices that detect and respond to changes in an environment with inputs from a variety of sources such as light, temperature, motion and pressure. To facilitate efficient use in a broad mix of end-use environments, particularly harsh environments, sensors need to be protected to ensure reliability and performance especially within the remit of critical applications such as hazardous gas detection. For instance, a temperature sensor on a static device will have to withstand the temperatures within that immediate environment and any thermal shock or cycling that may take place. As an example, let’s look at a temperature sensor as part of a wearable device. It has the added consideration of physical interactions; the device will be moved, worn, will receive impact, will be flexed and will potentially be exposed to a number of additional elements, such as water or chemicals. Therefore, it is imperative that these devices are protected sufficiently to ensure reliable performance when utilised in their end-use environments.

Protection for the exposed electronics/components can be afforded in the form of encapsulation resins, thermal management solutions or conformal coatings. The sheer number of variables within different applications can also generate another challenge and that is to select the most suitable protection compound. IoT devices collate and transfer data, whether it be direct to another device or system or via a sensor to record changes in information gathered. This connection to other devices may operate via radio waves and consequently any protection compound used, must allow RF signals to be transmitted without any interference. In addition to this, the environmental conditions and general use of the device must be considered to produce a full picture of its working life. Electrolube has recently provided a solution for a customer who required protection for a container of sensors, which is used for analysing the status of industrial machinery to prevent field failures within many different environments and sectors, such as petrochemical, food processing and offshore platforms. The box of sensors is required to communicate with a server to update the information held, reporting back to phones and tablets. This ultimately allows for predictive maintenance selection and scheduled downtime for maintenance rather than failures. The protection required a resin that would critically facilitate RF communication. Electrolube’s UR5118 solved the customer’s problem and matched their requirements perfectly for a resin that was opaque to protect their intellectual property, low permativity and fully enabling of RF frequencies. 

There are also resin solutions available for applications which require critical protection of the circuit design such as medical or military applications or other sensitive designs. Electrolube’s X-Ray Potting Compound is a specialist resin that ensures complete protection and privacy. After encapsulating the circuit, when x-rayed the circuit components and design cannot be seen, protecting the intellectual property and protecting the components from radiation.

Smart Home systems based on the IoT encompass a wide variety of applications for the digital consumer. IoT connectivity has allowed for areas such as lighting control (on/off/dimmers), voice-controlled items, security and locks, garden hydration, energy and water meters, heating, switches, and more. Electrolube was approached to develop a protective solution for a door sensor manufactured by an IoT smart home products manufacturer. The customer brief stipulated protecting the PCB from moisture, which was actively increasing current leakage and reducing battery life. The location was coastal and very humid. Initially, the customer had tried an acrylic based conformal coating, but this did not solve the problem as the battery typically discharged within 2-3 months.  The customer asked Electrolube for assistance and from our wide range of conformal coatings, we were able to make several recommendations, DCA, PUC and UVCL. Following extensive field testing, DCA was pronounced as the optimum solution satisfying all requirements including application method and cost.  

Smart Cities are also evolving and include the hypothesis of an optimised traffic system, enabling the smoothest flow of traffic possible, especially during peak hours. As you may imagine, the concept of one smart city cannot necessarily be automatically applied to another as the problems faced by one city are not necessarily identical to another. A few factors to be considered include air quality, disposal of waste, regularity of emergencies (for instance requiring police, fire or ambulance support), increase in urban concentration, environmental management, noise pollution and human behaviour. These parameters differ in cities all around the world and therefore affect each city in different ways. Planning organisations can use information gathered via IoT to analyse and plan for smart cities. Traffic signals will no longer work according to pre-set programs. Instead, they’ll respond to real-time traffic conditions, temporarily cutting stop times at certain intersections to clear congestion and then lengthening them again when possible. Better-circulating traffic means fewer emissions—not to mention happier drivers. 

Sensor technology will be sufficient to direct drivers to available parking spots, highlighting empty spaces on maps and offering directions to them. This will help reduce pollution by eliminating the endless circling of the area, looking for an empty parking space. Electrolube has collaborated with a customer to provide protection for a smart car park, where the level of protection needed to pot domed shaped sensors within a car park floor. The sensors not only had to withstand cars driving over them and be resistant to temperature extremes and water ingress, but also allow effective RF communication, whereby the signal can travel through the sensor and resin. UR5118 ticked all the boxes for this application with its dielectric constant of between 3-4 @50Hz, viscosity of 2300@23°C and 860@ 60°C and low exotherm (<35°C).

Agriculture is an industry that also lends itself very easily to applications within IoT. The world population is estimated to reach around 10 billion by the year 2050, resulting in much higher quantities of food required. To maximise agriculture, technology can be introduced and one of the prevalent methods is the concept of the Smart Greenhouse with controlled environmental factors that can increase yield and efficiencies. A simplistic example could be part of a crop requiring additional water or lighting and the sensor would highlight this, allowing the farmer to activate the appropriate switch or system via remote controls or via smartphone. The amassing and analysis of data illustrates clearly that this can be employed to maximise return and reduce energy, labour and resource usage. Electrolube was recently approached to provide a solution for an agri-tech firm who manufacture automated vegetable cultivation systems using hydroponic methods, which incorporates a soil-less method of farming, using different materials to support the roots of the plant and grow crops directly in nutrient-rich water. Hydroponics requires less space, less water and provides pesticide free, higher yields within a shorter harvest time. Electrolube’s general purpose, good all-round polyurethane potting compound, UR5064, is being used in this application for encapsulating a Total Dissolved Solids (TDS) sensor within the automated hydroponics system as well as an IoT based controller for water/ nutrition flow control. 

In the automotive industry, the technology involved in connected cars is huge and can be considered as a wide network of sensors, antennas and embedded software. This technology assists in the communication to navigate in our increasingly complex world and must be reliable first time, every time. An example of connective technology in vehicles is ACC Radar (Adaptive Cruise Control), which contains a sensor that analyses the changing speed of the vehicle travelling in front of you and links to your braking system, slowing your vehicle down to maintain your set distance with the vehicle in front of you. Electrolube has been involved in these applications with the usage of Electrolube’s thermal management product TPM (Thermal Phase Change Material) to offer thermal protection and maximise the lifetime of this sensor. 

Applications where RF signals are transmitted are rapidly increasing and the automotive industry is just one example; an increase in intelligent systems has resulted in information being transferred from various sensors positioned on a car to the dashboard display. The key property to refer to in this case is the dielectric constant or permittivity. High frequency devices, for example, would require a low dielectric constant of 3-3.5. These systems may include specialist fillers to obtain the lowest possible value, such fillers can also make the resin harder to mix and dispense due to the resultant high viscosity, however, using a specialist formulation and eliminating the fillers to achieve a slightly higher dielectric constant of 4, may result in the best compromise. In any case, it is important to test suggested resins to determine the optimum dielectric constant requirement for the application. Unfilled resin systems commonly deployed for RF applications include ER1448 – Unfilled Epoxy Resin, UR5118 Unfilled Polyurethane Resin and the SC2001 – Silicone Resin. 

Electrolube has many protection solutions for sensors used in IoT. Recent collaborations have included protecting a sensor within a fuel storage tank monitoring system. The sensor can detect the phase separation of the ethanol/water layer, which forms at the bottom of the tank, at its earliest stages of formation as well as measuring the degree of phase separation. The fuel storage tank monitoring system is also used to monitor fuel storage tanks for inventory tracking purposes, leak detection and water accumulation. Such accuracy requires the use of water-level sensors. Electrolube was approached by a manufacturer to protect the water level sensor. Electrolube’s two-part silicone potting and encapsulating resin, SC4003, is designed for the protection of electronic devices from challenging environments and answered all the protective requirements specified by the manufacturer. SC4003 cures at room temperature and provides excellent resistance to water and chemicals, it is also flame retardant and has excellent high temperature properties. 

A further collaboration with a temperature sensor manufacturer was found for a water temperature sensor. The solution was provided by Electrolube with the thermal interface material HTSP, Silicone Heat Transfer Compound Plus, with its advanced thermal conductivity even at high temperatures of 3.0 W/m.K. Electrolube has also developed a solution for a critical application with a large manufacturer of gas detection systems. The manufacturer required an encapsulation resin for a sensor control module, specifically for a gas detection device for use in hazardous areas. In any environment where toxic or flammable gases are used, generated, or stored, there is always a threat of employees getting exposed, a danger of explosions, or the risk of suffocation due to low oxygen levels. In such circumstances, gas detection and monitoring are very critical. This particular application’s protection requirements were solved with the two-part epoxy, flame retardant ER2188 general purpose potting compound. 

According to a Statistica report, the total number of connected devices in the world will be approximately 75.44 billion by 2025. IoT networks are known for their low energy consumption, low power transmissions and reduced number of data transfer through the network. It is essential that the devices on the network can operate for long periods, generate precise data and communicate with other devices on the network. Other applications may demand real-time data acquisition, exhibition of the collected information to users, long-range communications and battery-based devices. For effective operation and extended lifetime, electro-chemical solutions are a prerequisite for IoT applications.

Jade Bridges

Technical Manager – Electrolube

Jade.bridges@electrolube.co.uk

www.firefly-pr.com

0

Start typing and press Enter to search