An installation for enabling the scanning of a leg of a horse with a magnetic resonance imaging device comprises a floor section on which the horse stands with the leg to be scanned. The switching device according to the invention comprises a case containing at least one pair of contacts that can be reciprocally coupleddecoupled. Arrival times and required arrival times are propagated as parameterized random variables while taking correlations into account. The overflow section has a first end communicating with an overflow opening formed with the rain barrel and a second end extending away from the rain barrel. The compensation structure is formed of a material having a coefficient of thermal expansion less than a coefficient of thermal expansion of a material forming the substrate.