What pressure must totally enclosed inert gas-filled motors maintain within the enclosure?

Totally enclosed inert gas-filled motors require a positive pressure within their enclosure to ensure proper operation and safety. This positive pressure creates a barrier that prevents the ingress of potentially explosive or hazardous gases from the surrounding environment. By maintaining a higher internal pressure than the external atmosphere, the risk of any flammable gases entering the motor is minimized, which is crucial for preventing ignition in hazardous locations.

Inert gases, such as nitrogen or argon, can help to displace oxygen and further reduce the likelihood of combustion. Keeping the pressure positive helps to ensure that the inert gas remains contained within the enclosure and provides a protective environment for the motor components.

Other options such as negative pressure, neutral pressure, or static pressure would not provide the same level of safety and could potentially allow dangerous substances to infiltrate the housing, thereby increasing the risk of an explosion or fire. Therefore, maintaining positive pressure is essential for the safe operation of these motors in hazardous environments.