Mobile Equipment Inverter/VFD Repair
Case Study
Mobile Equipment Inverter/VFD Repair
Problem faced:
A manufacturer of bus climate control systems was faced with repairing over 150 Parker SD2 inverter drives responsible for powering the air conditioners on large city buses. There was an increased sense of urgency due to the quickly approaching summer season. In order to keep the buses running and the passengers cool and content, the manufacturer needed to get all of the aforementioned inverters repaired and returned in a limited amount of time – what in the repair industry is known as a ‘Hot Rush’. Having been a loyal customer of AFi for many years, they did not hesitate in putting their faith in AFi Systems' capability of processing this repair order in a very short period of time.
Introducing:
Parker MB2 Series Motor Controller
The MB2 mobile motor controller product line represents Parker's newest option for on-road or off-road hybrid electric and all electric vehicle platforms. This highly efficient IGBT power electronics device is capable of controlling AC induction and AC permanent magnet motors.
With a very rugged design, optimized cooling channels, and enclosure, the MB2 Series meets stringent mobile requirements. Supported by Parker's background in controls technologies, the MB2 is designed with multiple digital and analog I/O options and CAN communication. Its 4-Quadrant design enables full regenerative operation.
Parker Documentation MB2 Series Mobile Inverter.pdf
AFI Systems solution:
AFi Systems chose a small team of experienced technicians and dedicated them to completing the mobile inverter repairs in a professional and timely manner. As the inverters came through in batches, they went directly from receiving to the benches for evaluation and repair. Of the 158 drives received to date, only 10 of them were deemed unrepairable, due to excessive damage caused by overvoltage conditions. The rest were repaired and returned to the customer with an average turnaround time of 7 days. The customer was able to rest easy knowing that AFi Systems was a reliable business partner, helping to increase their overall efficiency and reduce their repair turnaround to their customers, which in turn allowed them to focus on other matters at hand.
Common issues faced during Mobile Inverter Repairs
Mobile Inverters within the transportation industry, also known as mobile inverters, commonly face spikes in DC voltage from the generators or alternators that supply their power. These spikes commonly lead to blown components, sometimes invisible to the naked eye, but often will burn-out the IGBT power modules and circuit boards. During the initial visual evaluation, these failures were easily identified by AFi Systems' trained technicians.
Blown Capacitors
One of the first, most obvious signs of component failure is blown capacitors. This can be due to over voltage, but is sometimes a result of environmental conditions, such as heat, or age.
Damaged Trace Lines
Another common fault is damaged trace lines, these can be the cause of the inverter board failure, but can also be a side effect of other blown components nearby on the board.
Various Methods for Testing Failed Inverter Drives
What the eye cannot see in an initial examination requires extra attention. Various methods for testing and diagnosis are performed by AFi Systems to both determine the cause of failure and ascertain that repairs are complete and durable. From examining boards under the microscope to running extended duration testing by connecting the inverters to motors, AFI systems assures that each of these inverters has an extended life span that will power the A/C systems on city buses for years to come.
Focus on AFi Professional Repairs
Express Return Shipping and Handling
AFi Systems has a large staff of highly experienced technicians that can quickly turn around industrial inverter repairs in any industry. We not only pride ourselves on professional, quality electronic repairs, but also on understanding that the job is not complete until the customer is back up and running 100%. Immediately after the repairs were complete, our shipping department went into high gear, properly packaging the inverter drives for shipment. AFi’s many years of experience has taught us the proper way to package and ship electrical components so as to assure the inverters’ performance upon arrival.
Conclusion:
The air conditioning system manufacturer was faced with a problem, quickly repairing a large number of Parker SSD inverter drives in order to power the A/C units on city buses. Their solution was to partner with AFi Systems in order to assure a quick turnaround on repairs in order to be ready for the summer transportation season. The results were as expected. AFi Systems was able to repair over 150 inverters with an average turnaround time of 7 days.