VLT® Compact Starter MCD 200 Due to extensive use of the latest technology, such as new semiconductor control algorithms, the new soft starters are very compact and heat dissipation is very low. There is no need for extra ventilation or bypass contactors, which simplifies installation and keeps panel space at a minimum. VLT® Soft Starter MCD 500 is an integrated motor starting solution. Current transformers measure motor current and provide feedback for adaptive control of motor ramp profiles. AAC (Adaptive Acceleration Control) automatically employs the best starting and stopping profile for the application.