| 摘要 |
A thermoelectric cold junction compensator connector module, for use with a thermoelectric device such as a thermistor, thermocouple, or resistance-temp erature device, has within a housing a cold junction compensator circuit which has means for lin earization of voltage output of the circuit relative to input to the circuit. Preferably the circu it also includes potentiometer means for adjustment of at least one parameter of the circuit, and means for adjustment of its voltage output to correspond to degrees Centigrade and deg rees Fahrenheit. In a preferred form there are included within the housing a pair of input te rminals shielded by ferrite material against stray electromagnetic induction signals, a printed circuit board which comprises a cold junction compensation circuit, a signal linearization circu it, a converter/amplifier circuit, and a circuit for selectively providing a degre e Centigrade and degree Fahrenheit output, a battery power supply, and a battery status indicator wi th means for bringing it into and out of operation, a plurality of potentiometers for preliminary setting up of the circuits, an on-off switching means for the powered circuits, and output ter minal means for connection to, for example, a voltmeter or a voltage recording device. The c ompact body may have a base portion on which the circuits and other items are mounted, and o ne or more removable cover portions securable on the base portion. Further, a thermocou ple voltage-to-analog connector is in the form of a compact hand-held module which contains all th e components and power supplies for converting an input of thermocouple output voltage to a linear and cold-junction-compensated analog output. A particularly advantage ous feature is that an on-board analog-to-digital converter only calculates and provides the lin earity correction, necessary for the specific thermocouple at a specific temperature, in the fo rm of a pulse width modulation signal output, so that about 95 % of the analog output is derived from the output of a thermocouple amplifier and temperature sensor, and only 5 % of the remaini ng signal is derived from the on-board micro-processor.
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