Calibration of conditioning amplifiers for dynamic application : Guideline DKD-R 3-2

Sensors for kinematic or mechanical measuring variables such as acceleration, angular velocity (rotation rate), force, torque or pressure are extended by a conditioning amplifier to be connected to data logging and/or display systems. In combination with this amplifier, the sensor forms a measuring chain. To ensure the exchangeability of the components of this measuring chain, sensor and amplifier are to be characterised individually. This guideline describes validated methods for the characterisation of conditioning amplifiers of different types and functions for application in dynamic measurements. The response of time changing signals is of particular interest. It is described by the complex transfer function as a function of the frequency of the input signal. For the purpose of this guideline, the amplifier to be calibrated is assumed to be linear so that the complex transfer coefficient at a given frequency is independent of the amplitude of the input signal. Other characteristics of conditioning amplifiers such as temperature influence, noise etc. are not covered by this guideline. The following technical specifications help to define the scope of the guideline: · Input measuring variables: Voltage, charge, resistance (voltage ratio) · Output measuring variables: Voltage (for digital outputs) · Typical frequency range: DC (0 Hz) to 100 kHz · Transfer characteristic variables: magnitude and phase of the complex transfer functio