摘要 |
<p>In a three-wire RTD interface, a known current is connected to a first lead during a first measurement interval. In this configuration, current is directed to the first lead and into an RTD. This results in a first signal indicative of a first voltage drop resulting from the voltage drops across the RTD and the lead resistance of the first lead. During a second measurement interval, current is directed through a second lead having a lead resistance substantially identical to the lead resistance of the first lead. This results in a second signal indicative of the voltage drop resulting from the second lead. The first signal, the second signal, and the known current are then combined to eliminate the effect of the lead resistance and to determine the resistance of the RTD.</p> |