A sensor 2 of a data collection system 2 is designed to make, in
a predetermined environment, an operation of writing output data of a sensing circuit
24 into a non-volatile memory 22 as reference-value data, and, in
a measurement environment, an operation of transmitting output data of the sensing
circuit and reference-value data stored in the non-volatile memory, under the control
of a memory control section 25, thereby selectively performing by itself
the data-writing or data-transmitting operation without receiving instructions
from a readout device.
