Aiming at the problem of multi-variable comprehensive measurement, a multi-physical quantity group effect idea is proposed, which represents multi-variable measurement results in a multi-dimensional vector space with the samecommon time base, and shows the coupling, correlation, causality, and time sequence among them. It also explains tThe status, function and value of the delay time difference between channels in data acquisition system are explained., and introduces tThe method of using the delay time difference between channels to quantitatively evaluate the synchronization difference of different channels is introduced, and the time base compensation and correction of multi-channel synchronous acquisition is presented. Finally, the synchronization interface of data acquisition is extended to the measurement terminals of the sensor of in each channel.