Temperature control apparatus.

摘要

Temperature control apparatus for use e.g. in an air conditioner, utilises a thermistor (21) as a temperature detection device. The thermistor has a non-linear temperature/voltage characteristic which is compensated for, by means of a processor (14). The voltage output developed across the thermistor (21) is converted to digital form, and the processor (14) is pre-programmed with data concerning the non-linear relationship of the detector impedance versus temperature, which is used to compensate for the non-linearity of the thermistor. The stored relationship is of the form $where\; x\; is\; the\; impedance\; value,\; a\; is\; a\; constant,\; and\; t\; is\; the\; temperature,\; n\; being\; an\; integer;\; for\; example\; n\; =\; 3.\; As\; a\; result,\; the\; thermistor\; can\; be\; used\; over\; a\; much\; larger\; sensing\; range\; than\; hitherto.\mathop{\mathrm{image}}$