Predictive maintenance and optimal use of resources
NORD DRIVESYSTEMS is developing cost-efficient and reliable virtual sensor functions for condition
monitoring.
Illustration: In applications with steady long-term load profiles, the drive PLC determines the best oil change
interval without costly sensors
The meaning of virtual sensors is explained using the oil lifespan as an example. This is to empower drive
technology to schedule maintenance dates solely based on calculations, with no expense for hardware
sensors. The onboard PLC evaluates extensive operational datasets on current, voltage, and speed. From
this data available in the inverter, the drive is always able to indirectly infer the current oil temperature.
Taking product-specific characteristics of the lubricant into account, oil aging can be determined, allowing for
optimal utilization of the lubricant. NORD has validated through testing that the calculated oil temperature
curve is nearly congruent with the real, measured temperature curve. Working up to launch a fully
operational solution soon, NORD is currently validating temperature curves under various load conditions.
Predictive maintenance functions are expected to be commercially available in all NORD drive electronics
units with an onboard PLC from late 2018.
AT A GLANCE: Virtual sensors for predictive maintenance
- Function in frequency inverters with an integrated PLC
- Precise definition of maintenance intervals helps
- reduce operating costs
- increase plant availability
- Due for launch: late 2018
- Pure software solution without hardware costs for sensors/control units
Company background
NORD DRIVESYSTEMS develops, produces and sells drive technologies with around 3.400 employees, and
is one of the international leaders in the industry. In addition to standard drives, NORD supplies
application-specific concepts and solutions, even for special applications, for example with energy-saving
drives or explosion-protected systems. Gross sales amounted to approx. EUR 540 mn in the 2015 business
year. The company founded in 1965 now has over 36 subsidiaries worldwide. The closely meshed sales and
service network ensures optimum availability for short delivery times and customer-oriented services. NORD
produces a wide variety of drive units for torques from 10 to 200,000 Nm, electric motors with powers from
0.12 kW to 1,000 kW as well as the necessary power electronics in the form of frequency inverters and servo
controllers. Inverter solutions are available for classical installations in the switch cabinet and for
decentralised and fully integrated drive units.
www.nord.com