Wireless technology is a key enabler of asset management. In many cases, it works quietly in the background, such as when an operator or maintenance person is making their rounds and it is used to upload the resulting report over the plant Wi-Fi network to the central maintenance software.
According to IEC’s Electropedia, an asset is a physical entity or digital entity that has value to an individual, an organization or a government. When you think about it, that means it can be pretty much anything. Being able to track something is the first step in managing it. Keeping the asset working and able to perform its assigned role is a logical second goal of asset management. Combining these capabilities provides the following key asset management elements:
- Automate inventory control: Knowing what assets you have at any point in time.
- Physical asset monitoring: Knowing where assets are at any point in time.
- Precise maintenance management: Understanding the condition of assets.
- ·Loss prevention: Prevent loss of the asset itself or a negative impact on system reliability.
Because assets have value, asset tracking is one of the most widely deployed first-generation Internet of Things (IoT) applications. As IoT technology expands, the asset maintenance component of asset management will be the next logical area of growth.
In support of the above asset management elements, IoT-based sensor asset tracking solutions can provide broader visibility into three types of use cases:
- Asset identification: High-volume tracking of assets using very low-cost either reusable or disposables tags.
- Asset track and trace: Includes tracking the location of stationary or slow-moving non-powered assets using battery-powered sensors devices. Smart sensor solutions can also cover where an asset’s geolocation is traced including the ubiquitous access cards used for offices or to enter a facility.
- Asset condition monitoring: IoT applications that allow for remote monitoring of the condition, status or health of assets in the field.
The two most widely used wireless systems to collect asset information are RFID (radio frequency identification) and BLE (Bluetooth low energy). Passive RFID has the advantage of not requiring an energy storage device but can only respond to a read request from an active RFID Reader. Passive RFID is often used in conjunction with QR-codes for device identification. It is also used as a “stepping off” point to more detailed information access, for example, using alternate technologies with higher bandwidth with IEC 61406. This implementation can be used to create an intelligent device nameplate for the industrial automation sector.
Passive RFID tags have a read range from near contact to 25 m, while active RFID tags, which contain a power source, boosts their broadcast ability to 100 m.
Due to the low cost of the tags, typically a few cents, passive RFID is often used in situations where items are likely to not be returned.
BLE systems, on the other hand, usually establish their own wireless networks with a combination of Beacon and Hub devices. Many BLE solutions can incorporate mobile Bluetooth-enabled devices such as smartphones as a roaming hub, which helps simplify implementation and provides a convenient interface.
The ability to use consumer mobile devices as roaming hubs makes BLE a particularly common technology for location and tracking applications. It is one reason why several manufacturers include a BLE configuration interface in their devices.
Unfortunately, for the industrial environment, BLE solutions don’t function particularly well around metal or reflective surfaces. In addition, as we all know from personal experience, BLE devices also require pairing to connect.
Some other examples of asset tracking that we take for granted include BLE-enabled tags like my Tile for keeping trach of your personal belongings. Another BLE application example in a gas detector that also monitors for a “man down” situations when there is lack of movement for a configured period. It then notifies a central location to investigate.
BLE or other low-power wireless solutions, such as Zigbee, Ultra Wide Band (UWB), or Narrow Band IoT (NB‑IoT), can be made for relatively low cost and size. They are also suitable to collect and transmit small payload asset conditions data, including temperature, vibration peaks (not the full spectrum), torque and noise on rotating machinery. Such capability offers a high-value, high-maintenance application.
Not all asset management information will be collected wirelessly, but wireless connectivity significantly reduces the barrier to entry of collecting the data, which is one step in the process. Analyzing and interpreting the meaning of the data is where the value is found. Fortunately, cloud-based services are also lowering that barrier to entry as well.
