We have investigated the effect of edge localized modes (ELMs) on the total plasma current in JET tokamak plasmas using the earth leakage current detection circuit connected to the in-vessel saddle coils. These measurements, and the geometry of the saddle coil circuit, indicate that, in typical H-mode plasmas, up to ∼300 A (corresponding to a maximum of ∼150 A per MA of plasma current) can be deposited at each ELM in regions rather far away (∼50 cm) from the strike point position and divertor target plates. These current losses decrease with increasing ELM frequency (fELM), being practically below or around the detection limit for fELM > 60 Hz, and show some saturation for increasing diamagnetic energy losses for 'slow' Type-I ELMs at fELM < 10 Hz. The measurements reported here are consistent with the ELM phenomenon being associated to a peeling of the edge magnetic flux surfaces.
Characteristics of the edge localized mode in the JFT-2M H-mode