Vibration control is one of the most crucial improvements a generator manufacturer can make to better their product. By lowering the vibration on the generator, you reduce the noise and limit the vehicle's vibration. There are many factors to control vibration on an onboard generator set, and this case study demonstrates the steps taken by the team of PowerTech engineers.
An OEM reached out to our Midwest sales manager on a vibration issue with one of their medical coaches. The specific medical coach would be drawing blood right above the generator. It was essential to reduce the vibration to the point where the generator did not affect the employee's tasks.
The first solution to the vibration problem was to offer an airbag mounting system to the generator. However, this mobile medical coach was not equipped with an air compressor to keep the airbags inflated. The space above the generator was tight, and airbags sit higher than rubber mount systems when fully inflated. The sales and engineering team knew they needed a low-profile rubber mount solution for this custom generator. The PowerTech team consulted with our mount vendor and performed various tests.
The vibration analysis was carried out on an array of PowerTech generators utilizing the new mounts suggested by vibration attenuation experts, both in our laboratory and on a customer's vehicle. The generator was securely mounted to a flat, level steel workbench in the lab. The generators were tested at full load, representing the highest vibration situation for the units using a PCE-VT 2700 vibration tester, using a single axis transducer affixed to the generator with a magnetic base. The vibration was measured using displacement in thousandths of an inch. The PowerTech engineering group took measurements at each corner of the base pan from the x, y, and z-axis resulting in 12 measurements per testing cycle. Baseline testing resulted in an averaged displacement of 2.01 compared to the best performing mount, which rated at 1.06 removal, resulting in a net improvement of 52.7%. The new generator mounting configuration was applied to all PowerTech OPU and ENC-style generators.
After collecting intensive data and vibration calculations, PowerTech sourced a softer Puck/Mount that would satisfy their requirements, and they approved the configuration. The new mounts cut the vibration in half compared to the original mounts. After this experience, PowerTech decided to apply the change in mounts for all generators (vibration data available upon request).