What might cause overheating in a pressure compensated pump system during dwell times?

In a pressure compensated pump system, overheating during dwell times can occur when the main relief valve is set too low. When the relief valve is adjusted to a lower pressure, the system may continuously recirculate fluid back to the reservoir instead of allowing it to flow freely to the actuators or motors. During these dwell times, the pump is still working to maintain the pressure, leading to a situation where fluid is being diverted back through the relief valve at high flow rates, which can create excess heat due to the constant pumping action and minimal fluid movement in the system's active components.

Conversely, if the relief valve were set too high, it would allow the system to operate at higher pressures but could lead to the pump working harder than necessary, potentially causing other issues rather than overheating during idle times. Case drain blockage would trap fluid and cause pressure buildup, which usually leads to overheating but is more about physical obstructions than settings. Lastly, excessive fluid levels in the reservoir can also contribute to overheating by limiting the reservoir’s ability to dissipate heat, but the fundamental issue in the context of pressure compensation is how the relief valves regulate the system's flow and pressure during low-demand situations.