When aligning an electric motor to a hydraulic pump, why should the system be bled off and isolated?

When aligning an electric motor to a hydraulic pump, isolating and bleeding off the system is crucial mainly because high-pressure trapped oil could backflow through the pump. This scenario can occur if the pump is directly connected to a hydraulic system that is under pressure. Without proper isolation, any movement or adjustment during the alignment process risks accidentally releasing this trapped oil, which could lead to fluid spills or potential injury.

Maintaining a safe work environment is paramount, and ensuring that the hydrostatic pressure is released protects not only the components but also the personnel handling the alignment. This precaution helps to prevent sudden releases of pressurized fluid, which could cause accidents or damage to the equipment being aligned.

Other highlighted factors related to potential risks include temperature issues or energized components, but they do not directly address the consequences of trapped oil in the system as effectively as the risk of backflow does. Hence, the emphasis on isolating and bleeding off the system prior to alignment is grounded in ensuring safety by mitigating the risk of pressurized fluid release.