The resistance of commercially available RTDs ranges from 10 to 25,000 W. More common ones are 100, 200, and 1000 W strain-free platinum (>99.999%) probes and 10 W copper probes. Generally, the higher the resistance, the less affected the RTD will be due to small resistance/voltage fluctuations in the lead wires and circuit.
Common metals used in RTDs include platinum, copper, nickel, BalcoTM (70% Ni-30% Fe), and tungsten. Their temperature ranges are listed in the following table.
(70% Ni-30% Fe)