foreign amplitude Peak Peak to Peak RMS in the previous chapter we focused on the frequency of a vibration in this chapter we will take a closer look at the amplitude of a vibration as mentioned before the amplitude is depending on the stiffness of the construction but also on the applied force altering one of them will have an impact on the amplitude and or frequency the amplitude or the size of a vibration can be expressed with three parameters Peak to Peak zero Peak and RMS all three parameters are used when performing vibration measurements and each of them has its own added value this added value will be covered in detail in later modules during this training for now it is important to understand the relation between these parameters the peak to Peak or Top Value indicates the maximum results of the vibration the peak Peak value indicates the difference between the maximum positive and maximum negative amplitudes of a vibration waveform this is a useful value when measuring moving machine parts where the displacement is not allowed to exceed a certain value as this will result in mechanical stresses or machine damage examples of this are shaft vibrations both radial and axial vibrations and axial shaft displacements 2. the zero Peak value for a sinusoidal signal is half the value of a peak to Peak value basically this value is used when the peak Peak value has no added value for the signal evaluation the zero Peak value can be used to indicate single one-off or short events such as shocks and impacts this value can also be used to register pure harmonic sinusoidal motions the RMS value root mean Square also known as effective value is the most common way to express a vibration level for a purely harmonic movement the RMS value is one-half times the square root from the zero Peak value or 1 4 times the square root from the peak to Peak value in short or sinusoidal shaped amplitudes the RMS value is 0.707 times the zero Peak value or 0.353 times the peak Peak value the peak Peak value is 2.82 times the RMS value and the zero Peak value is 1.414 times the RMS value the peak Peak value is twice the zero Peak value for sinusoidal shape signals before we continue with the measurable quantities of mechanical vibrations in chapter 1.4 parameters displacement velocity and acceleration we'll briefly cover the potential effects of undetected excessive vibrations eight possible effects of machine vibrations monitoring vibrations provides better control over the safety and availability of your Machinery let's have a look at what might happen when excessive vibrations can develop undetected safety issues plant safety must be guaranteed at all times the sources of vibrations can often be resolved quite easily at an early stage however they can develop into serious safety issues if action is not taken when required not only can unidentified machine vibrations cause serious damage but more importantly they can cause human injuries and environmental harm machine damage when excessive vibrations are not identified at an early stage damage to the machine can occur in the most extreme cases the machine must be replaced entirely as a result of excessive damage reduced availability the availability of a machine could reduce as a result of excessive vibrations as it may be necessary to reduce the machine load unschedule downtime vibrations often develop gradually and are hard if not impossible to be detected without proper instrumentation as soon as they become apparent it is usually too late to take preventive measures and downtime is necessary for machine repairs supply issues unscheduled stops or reduced availability as a result of defective machine parts or damage could lead to production issues this is especially the case for plants where 24 7 production is required to adhere to supply agreements unnecessary maintenance machine parts are often replaced preventively to ensure machine availability even though this prevents unscheduled downtime there is a good chance that machines or machine parts are replaced unnecessarily before the actual end of life by monitoring vibrations repairs and Replacements are only performed when required we'll get back to this so-called condition based maintenance strategy further in this training semi-finished product when a machine has to be stopped or fails unexpectedly semi-finished products remain in the process in many cases these semi-finished products must be discarded this means that expensive raw materials are essentially thrown out or led to the flare quality issues vibrations could negatively affect the quality of the manufactured products we will now continue with the next chapter of the vibration training parameters displacement velocity and acceleration