What is the correct condition for the weight stack on a piston gage during operation?

The correct condition for the weight stack on a piston gage during operation is that it should be floating freely. This enables the weight of the stack to accurately apply pressure to the fluid in the piston gage, ensuring precise measurements. When the weight stack floats freely, it allows the piston to move without any restrictions or additional forces acting on it, which is crucial for maintaining accuracy in pressure readings.

In this context, if the weight stack were descending, it could imply that the pressure applied is changing or that the piston is not functioning properly. If it were to remain stationary or balanced, it might indicate a lack of proper movement or an incorrect application of the weight, which could lead to calculation errors in pressure readings. Therefore, allowing the weight stack to float freely is essential for the piston gage to operate effectively and produce reliable results.