Weight measuring apparatus for measuring a weight of fluids

A weight measuring apparatus to which containers containing fluids are fit, said weight measuring apparatus measuring a weight of the fluids, said weight measuring apparatus comprising:

• a first arm having a first fitting to fit a first container containing a first fluid;
• a second arm having a second fitting to fit a second container containing a second fluid, said second arm being connected to said first arm;
• a first measuring device that measures, as a first total weight, a total weight based on a change of said second arm, the total weight being a total of a weight of said first container fit by said first fitting and a weight of said second container fit by said second fitting;
• a third arm connected to said second arm;
• a second measuring device measuring, as a second total weight, the total weight based on a change of said third arm;
• and
• an alarm alarming, when the first total weight and the second total weight have different values having a difference equal to or greater than a predetermined value.