Final answer:
Motors with built-in thermal production do not always require external overload devices, but it is recommended to use them as an additional safety measure.
Step-by-step explanation:
In the case of motors that have built-in thermal production, external overload devices are not always necessary. Motors with built-in thermal production are designed to withstand a certain amount of heat generated during operation. However, if the motor is subjected to excessive current or load, it can overheat and potentially cause damage.
External overload devices such as circuit breakers and fuses can be used to protect the motor from overheating. These devices are designed to interrupt excessive currents and prevent thermal hazards. They automatically open the circuit when the current exceeds safe limits, thereby preventing damage to the motor.
So, while motors with built-in thermal production can handle some heat, it is still recommended to use external overload devices as an additional safety measure.