HOW DO I RESET OR RESTART THE MIXER AFTER IT JUST STOPPED IN MID MIX

Trina you might be better off to contact Hobart or an authorised Hobart service agent about this. The lack of answers probably indicates resident hobart experts are absent.

There is a good chance you burned up the electrical Connectors to the motor or you have have blown the FUSE that is located inside the housing. The Motor has a Self Shut Off when it overheats but if you have over taxed the motor more than once, then there is a good change you need to repair/replace it with something that can handle harder work. My sister got a Mix Master the same time I got my Kitchen Aid, My Kitchen Aid is running strong since 2003 and her Mix Master died in 2005 and I bought her a Kitchen Aid. Sorry but I am not fond of the Sunbeam Mixer's.... Quality has gone down hill over the years to keep their prices low.

Please elaborate.

there is gear damage inside unit. will need disassembly to evaluate damage.

You have broken the intermediate gear in the head. This gear can be a bit of a problem to change. Here is the parts manual for the KSM150PS.
The part is probably #6, worm gear.
Check with Kitchenaid on where to buy parts.

Mixer has a power control board inside the domed end cap. If it has failed then you this would cause these symptons.

chances are you have oerloaded the mixer or it is unevenly loaded give it a few mins it may have a safty and a reset button check you main fuse box as well the toggle may need to be reset

Take the mixer back and get a new one. I've had this happen too with KitchenAid's.

I dont know much about them but If you cannot get it repaired I do have a lift bowl stand mixer that I bought without the bowl or attachments that I would sell for $80.00 Or I will buy your attachments. Thanks, Mark.

Sounds like the hinge pin may have slid out of half of the base..