Overvoltage protection for RTD-based measurement ysstems Question: Is it possible to design a complete RTD module with overvoltage protection? Answer: RTD (resistance temperature detectors) can provide excellent stability and accuracy, and reduce the impacts of noise and interference. RTD sensors can be made up of either 2-wire, 3-wire, or 4-wire versions, and require an excitation current to produce an output voltage. AD7124-4/AD7124-8 contain two well matched current sources, a PGA, reference buffers, and diagnostic functions, which are ideally suited for high reliability RTD modules. Incorrect operations, careless connections, and exposed wires usually lead to overvoltage faults in industrial circumstances, which will damage the electronic devices and cause undesirable consequences that may flow from the damage. Overvoltage protection ability is a key specification for an RTD module. Outside of transient overvoltage protection, durable overvoltage protection must be considered during actual production.