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ET2SN · 01-02-18, 12:17 PM

Well, to go even deeper-

The OP mentioned electric motors as a kind of justification but even that is shaky.
My first boat was the Barbel. Three standard navy diesels that turned generators which fed the battery wells which then fed two large electric motors coupled to a common shaft. No reduction gears and you still wouldn't want to just chuck it into reverse.

The best way to torture an electric motor is to do what's known as a Blocked Rotor Test. The motor sees the maximum possible amperage load and if the windings, cables, and brushes don't burn or blow up- you've got a good motor.

Now imagine the stress of reversing the field while the motor is running near its rated speed (at some point you'll also block the rotor for a couple of seconds).

01-02-18, 12:17 PM	#10
ET2SN Ocean Warrior Join Date: Oct 2017 Posts: 2,652 Downloads: 60 Uploads: 0	Well, to go even deeper- The OP mentioned electric motors as a kind of justification but even that is shaky. My first boat was the Barbel. Three standard navy diesels that turned generators which fed the battery wells which then fed two large electric motors coupled to a common shaft. No reduction gears and you still wouldn't want to just chuck it into reverse. The best way to torture an electric motor is to do what's known as a Blocked Rotor Test. The motor sees the maximum possible amperage load and if the windings, cables, and brushes don't burn or blow up- you've got a good motor. Now imagine the stress of reversing the field while the motor is running near its rated speed (at some point you'll also block the rotor for a couple of seconds).