An electrical assembly comprises a plurality of modules (36), each module (36) including at least one switching element (38) and at least one energy storage device (40), the or each switching element (38) and the or each energy storage device (40) in each module (36) arranged to be combinable to selectively provide a voltage source, wherein each module (36) includes a respective sensor (46) that is configured to monitor at least one other of the plurality of modules (36), each sensor (46) configured to selectively detect an occurrence of an operational hazard in the or each corresponding monitored module (36).