IIoT Sensors

Introduction

Industrial Internet of Things sensors form the backbone of data acquisition and monitoring in connected industrial ecosystems. In this in-depth tutorial, we will explore the Power of IIoT sensors, answering fundamental questions and providing a comprehensive understanding of their role in the digital transformation of industries. 

What is an IIoT Sensor

An IIoT sensor is like a smart watchdog for machines in industries. It keeps an eye on them, providing real time data to maintenance teams. Unlike the old way of checking machines now and then, these sensors are always on the lookout for any issues. The power of IIoT sensors compared to traditional sensors is that these sensors can talk to the cloud, which is like a giant computer on the internet. This quick communication helps analyze data fast and makes it easier for people to make decisions.

Note | Instead of talking directly to the cloud, the sensors communicate with a middleman device called a gateway. 

This gateway collects information from multiple sensors and then sends it to the cloud.

In other way The IIoT sensors are industrial sensors with integrated sensor and computing functions that are connected to larger systems via wireless communications technology. Look at some of IIoT Sensors’ crucial functions:

• Continuous Monitoring.
• Real time Data Delivery to Maintenance Teams: This allows for swift responses to potential issues, minimizing downtime and preventing major breakdowns.
• Wireless Connectivity and Data Transmission: IIoT sensors transmit data and alerts wirelessly to platforms such as Control Systems, Edge, or the Cloud. This data assists companies in conducting advanced analysis and visualization for optimal decision making.
• Gateway Communication for Data Consolidation: collecting valuable information from multiple sensors and then transmitting it to the cloud. 
• Sensors and actuators: Sensors often work in conjunction with  actuators, but there are differences between them. While a sensor monitors conditions and signals when changes occur, an actuator receives a signal and performs an action. IIoT sensors enable remote, automated control of physical processes based on the actionable data they generate.

Popular Sensors Used for Industrial Automation

Let’s explore some Sensors:

Vibration Sensors

Vibration sensors can measure vibrations in different ways: as a displacement, a velocity, or an acceleration. When acceleration is measured, it can be integrated to velocity and doubly integrated to (periodic) displacement, which is what a vibration effectively is. The spectral content can be derived from the measurements: what frequencies are present in the vibration signal? This is important information, especially the changes that occur in the frequencies due to external (potentially maintenance-related) influences.

Vibration sensors can be used in an industrial IoT setting for collecting vibration data. This data can subsequently be analyzed either locally or in the cloud, for predictive maintenance or other purposes.

One of IIoT Vibration Sensors device is:

NCD Vibration Sensor

It is collecting data quick and safe. After, simply upload data to Edge Gateway and send data to preferred Cloud, User Interface, or Server.

Temperature Sensors

It’s used to measure temperature. This can be air temperature, liquid temperature or the temperature of solid matter. There are different types available and each use different technologies and principles to take the temperature measurement and they are:

• Thermistors: They measure temperature by measuring the change in resistance of the electric current there are two types NTC and PTC type.
• RTDs: work in a similar way to Thermistors and measure resistance to measure temperature, but they have a much wider temperature range and can measure extreme temperatures.
• Thermocouples: two conductors, made up of different metals that are joined at the end to form a junction. When this junction is subjected to heat, a voltage is produced that is directly proportional to the temperature input. Less accuracy comparing to NTC’s and RTD’s.
• Semiconductor-Based Sensors: it is an electronic device integrated into ICs capable of measuring temperatures accurately within a range of -55 °C to 150 °C.

Let’s explore one of IIoT Temperature sensors:

BLIIoT RTU5023 GSM 3G 4G LTE Environmental Monitoring Alarm Device

We have a list for sensors connecting to it for measurement:

• AM2301 Temperature &Humidity Sensor, cable length 1m.
• AM2305 Temperature &Humidity Sensor, cable length 5m.
• AM2320 Temperature &Humidity Sensor, cable length 20m.

Some of it’s Mainly Features: 

• Up to 10 authorized phone numbers, 5 can be used to receive call or SMS, and 5 can be used to call and SMS while alarm occurrence.
• Support remotely read historic data via SMS.
• Support Modbus TCP and Modbus RTU over TCP protocol for cloud monitoring.
• Secure - Using caller ID and password for identification, unknown callers are ignored.
• Programmable by SMS Commands or APPs with password protection.

Proximity Sensors

It’s a sensor able to detect the presence of nearby objects without any physical contact. A proximity sensor often emits an electromagnetic field or a beam of electromagnetic radiation and looks for changes in the return signal. Proximity sensors can be:

• Inductive: detect metal objects;
• Capacitive: detect all objects including non-metallic ones.
• Magnetic: non-contact proximity device which detects the magnetic objects.
• Ultrasonic: they are widely used in automotive such as parking sensors.
• Optical: they recognize, for non-contact and precisely, the positioning of the object.

Let’s explore one of IIoT Proximity sensors:

NCD Proximity & Light Sensor

Pressure Sensors

A pressure sensor is a device that senses and measures pressure. In this case, pressure is defined as the amount of force exerted over an area. Pressure sensors allow for more 

These sensors are used to observe pressure changes in gasses and liquids that your industrial facility may be working with.

Let’s explore one of IIoT Pressure sensors:

Omron E8PC

Some of its Features:

• Multi-sensing of "pressure + temperature" to prevent sudden stops or manufacturing defects.
• Various adapters are available to enable easy replacement of your current pressure gauges and flow meters.
• Includes an analog current output function in addition to the IO-Link communications function that is used to perform self-diagnosis of abnormalities in the sensor itself.

Gas Sensors

Gas sensors monitor and detect changes in the air.  These sensors are vital to our safety as they’re able to detect the presence of potentially harmful or even toxic gasses.

They are most commonly used within the mining, oil and gas, and chemical research. However, gas sensors are also prominent in most homes via carbon dioxide detectors.

Let’s explore one of IIoT Gas sensors:

SenseCAP Sensor Hub 4G Data Logger

The SenseCAP Sensor Hub is compatible with standard MODBUS RTU RS485 connections, which means that it can be used with most industrial grade sensors to send collected data to the cloud.

Some of its features:

• Simultaneously collect a variety of environmental data.
• Supports local storage of data.
• Compatible with standard MODBUS-RTU RS485 sensors.
• Support 4G/3G/2G communication, supporting global LTE frequency band
• Built-in GPS positioning function.
• Remote upgrade and maintenance capable
• Easy to install and deploy, without requirements of engineering background
• Industry standards, suitable for harsh outdoor environments

Humidity Sensors

Humidity sensors measure the amount of water vapor in the air. In scientific terms, they measure the amount of moisture or humidity in specific environments.

This kind of sensor is usually used in addition to temperature sensors when a manufacturing process requires absolute perfect working conditions.

They’re usually found in heating, ventilation, and air conditioning (HVAC) systems.

Let’s explore one of IIoT Humidity Sensors:

The Sentrius™ RS1xx temperature and humidity sensors

It enables battery-powered, local and wide-area sensor applications using LoRaWAN and Bluetooth 4.2! The RS1xx are small, rugged, and easily configurable sensors making it easier than ever to monitor environmental data with your own network of sensors.

It has its own mobile app too.

Level Sensors

Level sensors are usually installed to monitor levels of fluid, powders, granular materials, or chemicals in particular equipment.

They are used in many different industries and applications:

• Oil manufacturing.
• Beverage manufacturing.
• Food manufacturing.
• Water treatment.

Let’s explore one of IIoT Level Sensors:

Intellia Wireless Ultrasonic Sensors INT-D-02

Some of its Features:

• Single platform for monitoring necessary parameters.
• Live Location tracking of tanks with volume status.
• Liquid level supervision for each corresponding day.
• Real time calculated volume based on liquid level data.
• Remotely manage through web & mobile apps.

Infrared Sensors

These sensors emit or detect infrared radiation or measure released heat. Infrared sensors can help monitor things like blood flow in health care applications or remote control signals.

And one of Infrared Sensor is PIR Motion Sensor which is used in Motion and Human detection, and one of IIoT PIR Motion Sensor device:

NCD IoT Long Range Wireless PIR Motion Detection Sensor.

Some of its applications:

• Wireless Industrial Area Monitoring.
• Motion Detection.
• Human Presence Detection.
• IoT Security Applications.
• Wireless Human Motion Monitoring for AWS® and Azure@.

Air Quality Sensors

Air quality sensors are used to maintain healthy work environments for factory or production plant staff as these facilities can produce harmful fumes and toxins, so it’s an indicator of how clean or polluted the air is, And It is measured with the Air Quality Index (AQI) that uses numbers from 0 (good air quality) to 500 (hazardous air quality that represents an emergency) to indicate the concentration of pollutants in the air at a specific site which may be:

• Carbon monoxide (CO).
• Carbon dioxide (CO₂).
• Particulate matter.
• Ozone.
• Volatile organic compounds (VOC).

Let’s see one of IIoT Air quality sensors:

ES101CO Outdoor CO Carbon Monoxide Sensor for air quality monitoring.

Outdoor Protective Design:

• Prevent direct ultraviolet radiation to the sensors
• Avoid rapid aging of sensors under harsh environmental conditions.
• The sensor parts are ventilated for truly sensing the changes in external detection parameters.
• Single or multiple parameters both can use small shutter, small size, lightweight and easy to install.

Some of its features:

• Support Modbus protocol.
• Real-time online monitoring, analysis, reporting.
• Remote cloud security and visual management.

Current Monitoring Sensors

They provide accurate power consumption readings that help keep utility bills under control and facilitate sustainable operations. And ability to forecast machine failure.

Let’s see one of IIoT Current Monitoring sensors:

NCD 2 Channel Industrial IoT Wireless AC Current Monitor Sensor.

Some of its Applications:

• Industrial Current Monitoring.
• Pump, Motor, Generator Electrical Behavior Analysis.
• Current Abnormality detection.
• Handheld Current monitoring equipment.
• Key component of predictive maintenance.
• Current Measurement to Cloud like AWS/Azure.

Now let’s talk in brief about other types of sensors.

Theft Sensors

Theft detection systems continually monitor assets or environments to detect suspicious activity and send alerts to operators. And the major use of theft sensors is in the retail industry. Currently, the theft sensor is fixed with the valuable items to prevent them from getting stolen or the expensive tools and assets to stay in the acceptable location. 

Also they can be applied in electrical utilities, museums, warehouses, or any other site where a theft attempt may take place. Video cameras, proximity sensors, and other data sources can used to identify unauthorized access.

Speed Sensors

Industrial speed sensors are imperative for ensuring that your machinery is working properly. They can quickly alert employees to operational issues that need to be addressed by monitoring the speed or direction of a rotating shaft. Moreover, if a significant problem is detected, they’ll quickly shut down the machine to limit damage from faulty mechanics.

What are the most important types of IIoT sensors

The landscape of IIoT sensors is extensive, encompassing various types crucial for diverse industrial applications. 

IIoT sensors primarily serve the essential function of monitoring process- and safety critical components. Especially, vibration sensors play a pivotal role in identifying potential issues by detecting abnormal vibrations. Pressure sensors contribute significantly to preventing damage, while temperature sensors are vital for monitoring assets at risk of elevated temperatures and preventing product spoilage. To ensure the proper operation of plant assets, both independently and in conjunction, physical data is indispensable, and this is where wireless positioning and proximity sensors come into play.

How IIoT Sensors Work 

At its core, sensors simplify the complex they convert physical traits into measurable electrical signals.

These signals form a language through which algorithms spring into action when measurements are abnormal. 

The operational framework of IIoT sensors involves several key stages:

1. Sensing Physical Data: IIoT sensors are designed to monitor specific physical parameters such as temperature, pressure, humidity, vibration, and more as we discussed above. Integrated into industrial equipment, machinery, or devices, these sensors continuously collect data about operating conditions.

In brief, in this stage Sensors Collect signals and turn them into data. 

2. Data Transmission: Collected and processed data can be transmitted in real time Using Network protocols just as example MQTT or suitable communication protocols to centralized systems, control systems, edge devices, or directly to the cloud.

In the figure below we will see that AWS IoT Core Enables to communicate with different IoT devices so we can get data from IoT Sensors and then make all different operations on the data using different AWS services.

3. Wireless Connectivity: Also data can be transmitted using Wireless as we discuss above there are wireless sensors that send data to Gateway using wireless communication technology then data can be transmitted from the Gateway. Let’s see a network of wireless sensors that collect different types of data and all send their data to the same gateway next to the cloud.

Now Sensors sense physical quantities then convert it into Data this data can be transmitted using different Communications protocols to different systems platform or to The Cloud, now we get data so let’s see what the importance from getting data into different system:

1. Storage Data: Data can be stored and organized in different databases. 
2. Data Processing and Analysis: We can use Cloud computing resources for utilized advanced analytics, data visualization, and large scale storage too. 
3. Decision Making and Automation: After analyzing Data a better decisions can be made also triggering automated responses or providing insights for human operators, this enable energy efficiency, and overall operational optimization
4. Remote Monitoring and Control: remote monitoring and control of industrial processes, equipment, or assets depending on analysis of receiving Data.

We can say in the realm of IoT or IIoT, multiple components join forces seamlessly. Picture it like a team effort involving sensors, the cloud, data processing, and a user friendly interface. Let's break it down into a simple point:

1. Sensors.
2. The Cloud.
3. Data Processing.
4. End User Interface.

Send data Using PLC with traditional sensors to Cloud

As we discussed above we know now that IIoT sensors transmit its data to IoT gateway then to the cloud it’s the same here we can use traditional Sensors connecting to PLC and connect PLC to an IIoT Gateway using suitable communication Protocols then this gateway can transfer PLC sensor’s data to The Cloud, let’s explore this operation.

1. Using any suitable Gateway for PLC

We mean by suitable here that the PLC and the Gateway device have the same communication Port.

2. We can use Node-Red

We can use edge devices Like Raspberry PI as a gateway to send PLC’s data to the Cloud.

Note | now we know how IIoT Sensor work and how to transmits Sensors data connecting with PLC to the Cloud so now let’s explain something important as all we discuss above we notice that IIoT sensor devices  consist of 3 component first one is the sensor and second one is the device with Communication and final one is the gateway and if we have a plc we know how to transfer Sensor’s data to the cloud let’s stop here what if the operation in the factory uses only Classic control components so we don’t have devices or PLC to get data from the sensors we have two solutions here first one is to get a gateway with I/O module and connect directly with sensors but if the gateway doesn’t have I/O module ? Here the second solution is to get edge devices connect to sensors to get data and then these edge devices communicate with gateway finally gateway send data to Cloud. 

Benefits of IIoT sensors

IIoT sensors play a pivotal role in enhancing operational efficiency, data integration, and cost effectiveness for businesses. Benefits of IIoT can be considered in three general Benefit which are:

1. Monitoring Improvement 

IIoT sensors provide 24/7 monitoring of critical equipment instead of relying on periodic manual checks. This can be especially valuable in collecting data from assets that are remotely located. Sensor alerts can be sent from scattered equipment and gathered in a centralized computer system.

2. Cost Savings

The price of sensors themselves have dropped significantly in recent years. Sensors also reduce labor costs in equipment monitoring. By triggering less expensive preventive maintenance tasks, sensors can reduce the amount spent on major problems or emergency repairs.

3. Integration Capabilities

Sensors data can be sent to a computerized maintenance management system (CMMS) for analysis. This allows maintenance managers to look at historic trends of particular assets, as well as pinpoint failure spots and frequency. This integration of data generates the information to make better future business decisions

But they are also especially important for Predictive maintenance so let’s explore it more briefly.

Predictive maintenance

We can brief the way of predictive maintenance by using IIoT into 4 stages:

• IIoT Sensors: collecting data.
• Data Transmission: Transmit the collected data to the Cloud.
• Storage Data: Storage and Analysis Data.
• Predictive Analysis: according to the analysis of new data and all past data we can make predictive Maintenance decisions for equipment. (it is also done by using Ai and ML technique)

Conclusion

Having the knowledge about the wide range of IIoT sensors along with their functionalities can help the industries in analyzing their procedures and then integrate the most useful sensor as per their requirements. IoT has changed the way humans live and industries work, and in this regard, the sensor companies are revolutionizing and innovating at a faster pace to enable industries in automating procedures. Furthermore, oil and gas, fleet management, manufacturing, healthcare and agriculture are the most important industries that can significantly benefit from IIoT sensors.