Perpetuum has launched a vibration-energy harvester to power wireless and battery-free devices that can send large amounts of data from many types of industrial equipment (see figure). The PMG7 microgenerator lets users power sensors, microprocessors, and transmitters for monitoring the condition of plant equipment and machinery without the need for batteries, cabling, or maintenance.
The microgenerator converts kinetic energy from the vibration of the equipment running at mains frequency (50 or 60 Hz) into electrical energy. It can generate up to 5 mW, which is enough to power a wireless transmitter sending up to 6 kbytes of data every few minutes, or smaller amounts of data—such as a temperature reading—several times a second. This practical device also can operate in most industrial environments and at minimal vibration levels (25 mg).
The microgenerator isn’t hard to install. Simply screw it into place or hold it in place with magnets. It then can be left in place with no need for maintenance.
RLW Inc. of State College, Pa., selected the Perpetuum microgenerator to power its wireless sensor nodes. In addition, field trials with Yorkshire Water, the U.S. Navy, and a major international oil company have proven the PMG7 a practical tool for continuous monitoring of plant and machinery.