Assessment of the quality of low cost data acquisition equipment for remote lab setups

When creating remote laboratories the designer can choose between many different solutions for the data acquisition system. The solutions range from using high-quality components from well established companies, such as National Instruments, to using discreet components in order to reduce the cost by gaining full control over the specifications for the solution chosen. Recently, open source, low-cost microcontroller board layouts based on microcontrollers from Microchip and Atmel have become available. The topic of this paper is the assessment of the quality of the data acquisition solution made available by the use of the internal analogue to digital converters (ADCs) of such low-cost solutions. The quality is analyzed in terms of measurement errors such as offset, gain and linearity errors as well as comparison of quantitative data from the datasheets. This analysis is an important tool for assessing whether the low-cost solutions are sufficient for running some or most of the remote laboratories, or if the increased cost of the budget solutions from professional acquisition modules can be defended. In this paper we try to give an answer to this question.