... the participant can assess the condition of the [electric motor] layer coils or layer windings [troubleshooting / testing]

sources:

The Electric Motor - Edison Tech Center
www.edisontechcenter.org/electricmotors.html

Winding or "Coil"- copper wires wound around a core to used to create or receive electromagnetic energy.

Wire used in the windings MUST be insulated. In some photos you will see what looks like bare copper wire windings, it is not, it is simply a enameled with a clear coating.

Copper is the most common material for windings. Aluminum is also used but must be thicker to carry the same electrical load safely. Copper windings allow for a smaller sized motor.

Burning out a motor, troubleshooting:
If a motor is run for too long or at excessive load, it may "burn up". This means that that the high temperature caused the winding insulation to break down or melt, the windings then short when they touch and the motor is damaged. You can also burn up a motor by putting more voltage into it than the winding wires are rated for. In that case the wire will melt at the weakest point, severing the connection. You can test a motor to see if it has burned out this way by testing for Ohms (resistance) on a multi-meter. In general you want to look for black marks in the windings when you check a motor.

How To Test Three - Phase AC Motors ~ Learning Electrical Engineering
www.electricalengineeringtoolbox.com/.../how-to-test-three-...
Three Phase Motors, AC Motors, Insulation Resistance. ... (d) AC Motor Winding Continuity Test (e) AC Motor ... Further troubleshooting maybe required. Power Supply Test For three phase motors, the expected voltage for a 230/400V system is 230V phase to neutral and 400V between each of the three phase supply lines.

How To Test and Check Single phase Electric Motors ~ Learning ...
www.electricalengineeringtoolbox.com/.../how-to-test-and-ch...
... (b) Earth Continuity and Resistance Test (c) Power Supply Test (d) AC Motor Winding Resistance Test (e) Insulation Resistance Test (f) Running Amps Test. General Inspections For the single phase motor, do the following: (1) Check the appearance of the motor. Check for burnt, damage to body or cooling fan or shaft.

Rewinding and Renovation of the Electric Motor: 45 Steps (with Pictures)
www.instructables.com/.../Rewinding-and-Renovation-of-the-E...
In next steps I will show you how do disassemble electric motor, remove bearings, make winding diagram, rewind motor, chose right capacitor and reassemble it ... is placed in 2 slots. Draw coils from your stator to your winding diagram. Do same for all coils. There cant be 2 coils in one gap (if you have Single-layer winding).

A new 4/6 pole-changing double layer winding for ... - ResearchGate
https://www.researchgate.net/.../224184667_A_new_46_pole-cha...
30 nov. 2017 - more pole-changing motors are equipped with two-layer windings, which allow adjusting the coil pitch for reducing the air gap mmf space harmonics. Conversely, two-layer windings are more difficult to insert in the stator slots,. M. V. Cistelecan is with the Research Institute for Electrical Machines.