The 7 Most Important Sensors For IT & Facilities Monitoring
by Michael Sigourney - Remote Site & Equipment Management - June/July 2007
Environment monitoring is an important function for facilities of all types including IT data centers, warehouses, schools, hospitals, offices, restaurants, farms, factories, zoos, museums and more. It’s something that we as humans do automatically. Think about it. When was the last time you got into your car without adjusting the heater or air conditioner? When you get home from work, don’t you adjust the thermostat, open a window or put on a sweater? Most likely you do.
We are unconsciously programmed to operate in a specific range of environment conditions because we want to be comfortable, know that it makes us more productive, wish to avoid getting sick and for a variety of other reasons. Without an awareness of the immediate environment, an individual will eventually put their productivity, health or very life at risk.
Environment conditions are also important for electronics, food, documents, medicines, machines and products of all types. This is a common understanding and such monitoring is typically needed on a regular, if not continual, basis. The advantage we have as humans is that we can monitor ourselves and make changes on the fly to maintain our environment. This is not true of machines, property or anything else for that matter. It is this understanding that has created a new market known as ‘IT & Facilities Environment Monitoring’; a market that Forrester Research predicts will surpass $11 billion annually by the year 2010. It is arguably considered the fastest growing niche in the computer industry and yet surprisingly remains ‘under the radar’ of many IT and facilities managers... at least until disaster strikes.
The ‘constant’ in environment monitoring is that change will inevitably occur. Important questions include: When? How? Why? Unfortunately, the answers to these basic questions are unknown, different for each organization and continue to change as time passes and environments are altered. Like always, there is no crystal ball for environment monitoring that allows a view of the future before it occurs.
Monitoring is clearly important when something of value needs to be protected, response time is critical and a change in environmental conditions can cause harm to people, property or an organization. Most managers recognize that to avoid monitoring altogether will expose them to a degree of risk that far surpasses the cost of even the most expensive monitoring solutions available. With automated solutions available worldwide, there’s no need to operate blind to potential environment threats at work.
Sensor Types: Digital vs. Switch
Before describing the primary sensor types available to monitor environment conditions, allow me to establish a foundation that we can build upon. First, there are two primary ‘types’ or ‘categories’ that sensors typically are divided into. Unfortunately, vendors often describe these with different terms. Don’t get hung up on the terms used as these are often confusing. Instead, focus on understanding the functional differences in how the sensors operate. For example, our company, AVTECH Software defines these sensor categories as ‘Digital’ and ‘Switch’.
Digital sensors are those that monitor in real-time to provide digital values that can be viewed through a web or application interface, passed in alert notifications and/or logged for creating charts and graphs. Common digital sensors include temperature, humidity and power. Respectively, these allow users to receive temperatures as a numeric value of Fahrenheit or Celsius, humidity as a numeric percentage of relative humidity (RH) and power as a numerical value of amperage, wattage and voltage.
Switch sensors are those that do not provide real-time values and instead present their status as a condition of being in or out of a specific state. These sensors have a built-in switch or circuit that changes status as a threshold is passed. The status is often referred to as being on/off, open/closed, make/break or above/below. Perhaps the most familiar example of a switch sensor is the traditional thermostat on the wall of your home or office. Popular switch sensors include power, flood, smoke, room entry and air flow.
Popular Sensors Address Common Concerns
In IT & facilities environment monitoring, there are seven primary concerns that are consistently of the greatest interest. These are referred to as the ‘Big 7’ and include temperature, power, humidity, flood, smoke, room entry and air flow. The order presented is intentional and the most popular automated monitoring solutions address concerns at the front of the list and continue from there. Leading vendors offer multiple models so organizations have options to choose from. In environment monitoring, there is no ‘one size fits all’ solution.
The most common events impacting environment conditions at a business include failure of a heater or an air conditioner, a loss of main power, high or low humidity, flooding or water leakage and inappropriate or unexpected human intervention. It helps to understand that although we are monitoring what some people call ‘mother nature’, the most frequent changes to a work environment are initiated by people. It is typically an organizations’ own staff that overloads power circuits, leaves doors open or unlocked, installs water cooled air conditioners above a computer room, blocks air vents, smokes where they shouldn’t, etc.
Let’s review sensors that can monitor conditions to immediately identify when a problem is developing. The objective is to give your staff the upper hand in monitoring environment conditions automatically in order to respond and resolve issues before they turn into a disaster. These sensors can be connected to an automated monitoring system that will allow you to be notified remotely, check sensor status from anywhere, log sensor data for later reference or graphing and even automate a response such as shutting down important equipment, turning on fans or pumps, starting a backup, etc. Automated monitoring systems are an inexpensive solution that can eliminate or reduce damage, protect valuable property or equipment and reduce downtime.
Temperature Sensor – a digital sensor that monitors temperature in real-time to produce numerical values that are read continuously and fed back to a monitoring system. These values are translated into Fahrenheit or Celsius for display via a web browser, sent to mobile devices and/or logged. Changes in temperature can indicate power failure, air conditioning failure, equipment malfunction, poor ventilation, etc. Extreme temperatures can cause damage to all sorts of products and equipment as a result of freezing or overheating. Leading digital temperature sensors monitor from -67° F (-55° C) to 257° F (125° C).
Power Sensor – a switch or digital sensor that monitors power supply. Switch based power sensors monitor power for a change of state such as on/off or off/on. Knowing immediately that a power loss has occurred is vital to most organizations, regardless of size. If computer equipment switches over to a backup power supply, there may only be a few minutes available to complete an orderly shutdown to protect valuable data and equipment.
A digital power sensor allows monitoring of the power availability and consumption that a specific machine uses and whether or not it is getting an adequate or consistent power supply. Values monitored include amperage, wattage and voltage. By utilizing this type of sensor, an organization can schedule start-up times for large machines in order to balance power load, reduce spikes in power usage and protect other pieces of equipment on the circuit from the negative effects of spikes or surges. Machines and equipment that no longer function properly can be identified for repair or replacement. Users can also verify a manufacturer’s claim about a machine’s power consumption before committing to the purchase of a large quantity of new computers or other equipment.
Humidity Sensor – a digital sensor that monitors humidity in real-time to produce numerical values that are read continuously and fed back to a monitoring system. These values are translated into relative humidity (RH) for display via a web browser, sent to mobile devices and/or logged. Changes in RH can indicate excessive moisture due to flooding or water leakage, air conditioning or humidifier failure, power loss, equipment malfunction, poor ventilation, sump pump failure, etc. Leading digital humidity sensors monitor from 0 - 100% RH.
It is important to monitor humidity in computer rooms and other environments where static electricity build-up caused by low humidity can damage sensitive electronics. Excessive humidity will cause mold, mildew and/or condensation that can damage property, impact the health of employees and animals, or spoil foods and medicines. The corrosive properties of moisture can impact sensitive equipment, paper records, packaging, artwork, antiques, automobiles and more. High humidity will also have a significant impact on people and their productivity.
Flood Sensor – a switch sensor that monitors for a change of state such as water being present or not. Knowing immediately that flooding or water leakage is occurring can be critical because water will damage almost everything. If it reaches electrical circuits it can damage valuable equipment, cause a fire and/or electrocute people. An alert from a flood sensor could indicate a water main break, restroom flooding, an air conditioning system that has water leakage, an elevator shaft filling up with water, roof or structural damage, etc.
There are two main types of flood sensors on the market; these are ‘spot’ and ‘cable’ sensors. As their names imply, spot sensors are designed for monitoring in a specific location and are often heavy duty sensors that are easy to install. Flood cables are more advanced and therefore more expensive. They allow for monitoring along the length of a custom cable so that monitoring can be accomplished along a wall or perimeter. Sensor cables are normally available in 8’ and 24’ lengths although leading vendors now make extension cables (typically in 8’ lengths) that can be connected to the main cable to create cables of longer lengths. This allows a single sensor to cover a huge area.
Both types of flood sensors have their advantages so full consideration should be made as to your objectives. Spot sensors are nice because they are typically more rugged, less expensive and easier to install. However, if you install the sensor in the wrong spot, you could be inches away from flooding and not be alerted because the water did not run directly under the sensor. Flood sensors with a flood cable are nice because they provide a much larger area for water to come into contact with the sensor. These cables can be tucked under the trim along a wall, wrapped around a pole or laid out on the floor to completely surround an area to monitor for water entering from any direction. The down-side is that cables can get expensive as lengths increase, take more planning time during installation and may need to be cleaned after 4-5 years in order to maintain full sensitivity. I personally recommend the 8’ flood cable for most applications as it offers the greatest value for the price.
Smoke Sensor – a switch sensor that monitors for the presence of smoke, fire or other noxious fumes. These sensors monitor for a change of state such as smoke particles being present or not. This is critical because smoke and fire will damage everything. This is a perfect example of a sensor that you install with hopes of never needing it. If it does go off, the time advantage gained can mean the difference between life and death, both for people and the business. An alert from a smoke sensor could indicate a fire, an electrical short, an open window, smoldering grease (i.e. in a restaurant), friction of machine parts, poor ventilation, people smoking where they shouldn’t be, etc.
Keep in mind that the location of smoke sensors is extremely important. Smoke sensors should be mounted on a ceiling or high on a wall, away from corners and in the air flow path where smoke will be carried towards the sensor.
Room Entry Sensor – a room entry sensor that monitors whether a door, cabinet or window is open or closed. These sensors are basically a set of magnets that trigger an alert when they are separated or joined together. The most common application is to mount this on the inside frame of a door to indicate that the door is open or that someone has entered the room. The primary benefit is to know that a room is secure or when people come and go. Some people purchase these thinking that they will operate as an alarm system. If your monitoring system is checking the sensor status every minute and someone opens and then immediately closes the door during that minute, you may not be alerted. That is to be expected based on the design of the technology used. If you need to know that someone passes through a doorway, I suggest using a motion sensor because they have a delayed reset function that can be detected several minutes after the sensor is triggered.
Air Flow Sensor – a switch sensor that monitors the air for movement or lack thereof. This could indicate a fan turning on or off, failure of an air handler or blower to keep air moving above a drop ceiling, through a rack, under a raised floor or through a vent, etc.
Proper air flow is a vital part of cooling as air circulation through an environment will help keep temperature and humidity more consistent. Without good air circulation, an environment is more likely to develop hot spots, waste power on over heating/cooling, encourage the development of mold, enable corrosion and create static electricity that can damage electronic equipment.
Special Sensors For Unique Applications
It’s easy to focus on the most common environment monitoring concerns above. However, other types of sensors will enable you to monitor unique situations or applications.
Sound Sensor – a switch sensor that monitors audible sound decibels for highs, lows or a change in sound level. This could indicate a break in, people where they should or shouldn’t be, equipment failure, audible alarm from a non-integrated sensor, an explosion, animal entry, inventory or structural collapse, vehicle collision, etc.
Light Sensor – a switch sensor that monitors for the presence or absence of light (i.e. turning on, off or a change in light level). This could indicate a break in, people where they should or shouldn’t be, power or generator failure, door or curtain open or closed, lightning strike, fire, refrigerator or cooler door open, rack cabinet panel removed, obstacle blocking an entryway, etc.
Motion Sensor – a switch sensor that monitors for the presence or absence of motion. These sensors are typically placed where a body mass moving through a specific zone could indicate a break in, people where they should or shouldn’t be, customer entry or exit, large animal entry (i.e. cows return to the barn), etc.
Panic Button – a switch sensor that is tripped manually by staff. This could indicate a robbery, medical emergency, simple need for assistance, overwhelmed employee needing manager help, manager needing warehouse staff to call the office, manufacturing line shut-down, etc. These sensors can be tripped momentarily or until they are manually reset.
Camera – use an IP network camera in response to other sensors that will capture snapshots of an environment, view live activity from a remote location via a web enabled device or record video for later review and/or long term archival. The camera can be initiated when events occur or on a scheduled basis for recording environment status, employee activity, customer volume, break-in, untimely entry, unexpected events, theft, violence, etc. Cameras may be installed as a legal requirement, for protection of people and property or as a warning to others that their actions are being monitored. Some cameras have a built-in switch sensor for motion that can connect to a monitoring system.
Additional sensor types can be found for many purposes. These range from simple to complex in regards to installation and use, from extremely reliable to ‘throw it away it never works’, and priced from inexpensive to ‘give me a break’ expensive. The objective is to implement sensors that will meet the specific needs of your monitoring application, integrate with an automated monitoring and alerting system and stay within the budget. It doesn’t matter how ‘cool’ a sensor is if it doesn’t meet your defined objective and costs more than you can afford to invest.
Don't Wait Until Disaster Strikes
Every organization will have their unique view as to what conditions need to be monitored and just how critical those issues are. However, the need to monitor what is important or valuable is common to us all. Should problems occur at your facility, and statistics say they will, questions will arise as to whether the need to monitor was known and why someone didn’t implement a monitoring system before disaster struck. Because the cost of an automated solution can start as low as $245 and the total risk to some organizations may be calculated into the millions, the question is why haven’t you implemented something already? My advice is exactly what you expect... Protect your facility before a disaster strikes, don’t wait until it’s too late.
There are two main types of flood sensors on the market; these are ‘spot’ and ‘cable’ sensors. As their names imply, spot sensors are designed for monitoring in a specific location and are often heavy duty sensors that are easy to install. Flood cables are more advanced and therefore more expensive. They allow for monitoring along the length of a custom cable so that monitoring can be accomplished along a wall or perimeter. Sensor cables are normally available in 8’ and 24’ lengths although leading vendors now make extension cables (typically in 8’ lengths) that can be connected to the main cable to create cables of longer lengths. This allows a single sensor to cover a huge area.
AVTECH Software, Inc.