Powering wireless Industrial Internet of Things (IIoT) sensors for applications such as machine condition monitoring is challenging. Sensors must be compact, robust, easy to deploy, inexpensive, and work reliably for long periods of time with little or no maintenance. The effects of sensor failure range from loss of vital data about machine condition to costly repairs to catastrophic failure of a system or production line.

What is condition monitoring?

Condition monitoring overcomes the problem of preventive maintenance planning for large and complex machinery and processes. The technology relies on knowing the state of machine components so they can be repaired or replaced before failure occurs. For example, by constantly monitoring the vibration signature of the motor, the software can determine the wear status of the bearings and infer when the current wear rate will lead to failure. Such information allows engineers to extend service intervals while avoiding unplanned downtime.

Without maintenance, complex industrial processes and machines eventually fail, resulting in extended downtime. Repeated failures of worn-out equipment continue to occur even after repairs (bottom). Preventive maintenance schedules frequent service intervals to ensure that processes and machines run for long periods of time and that machines do not wear out, but are resource-intensive (medium). Condition monitoring allows extended service intervals while reducing maintenance costs (top) without risk of failure.

IoT sensors are a good choice for condition monitoring applications. These compact devices can be mechanically attached near known machine or process failure points to improve measurement accuracy. Wireless connectivity allows for regular status updates without the need for expensive communication lines.

Power design challenges for IoT sensors are daunting. Typical application environments are dirty, there can be a lot of vibration, temperatures can be very high, and dangerous voltages are common. Space is often at a premium, and sensitive electronics require continuous, clean, and precisely regulated DC voltages.

Rugged Commercial IoT Sensor Power Modules:

Advances in packaging, such as the integration of power and control components on the same silicon die and the use of low-profile transformers, have enabled manufacturers to provide high-spec isolated DC/DC converters for IIoT sensor applications. For example, RECOM Power DC/DC converters use design elements such as planar transformers to shrink the chip height to less than 3 millimeters (mm).