The bag sewing machine started to twist in the opposite direction, what could be the matter?

Question

Electronics

Meshkozashivochny car Japanese newlong np-7a

Answer 1

If the motor is three-phase, the phases have been changed somewhere.
Wave any two phase wires between each other.

Answer 2

Someone put their crooked hands into the car.
The machine is mechanical, the motor is turned on with a button and spins, there are no firmware or chastotnikov.
The motor is a collector asynchronous, the direction can change if you disassemble it and switch a pair of contacts in the winding. Perhaps this is the result of an unsuccessful attempt to repair.

Answer 3

• Mixed wires on the engine or chastotnik.
  
• They mixed up the contacts for switching on the forward and reverse on the chastotnik.
  
• Climbed into the settings chastotnika and changed direction.
  

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