The pulse-discharge detector (PDD) uses a low-power DC pulse discharge in helium as an ionization source. The impulse discharge is observed between two blades, made of platinum wire, 1.5 mm apart. The discharge voltage is between 1-10 kV and its duration is from 20 to 60 μs. The detector enables detection of all compounds, including hydrogen.
Application:
Often used as a more sensitive alternative to the TCD detector.