Hinkley point temperature scanning equipment

The equipment described is a data handling system with mag netic drum storage. Approximately 600 graphite, fuel element and gas exit thermocouples are scanned and the remainder of the 720 input positions are used for self-checking purposes. It is a high speed system, taking 144 seconds for a complete scan; there is a store of 20 scans, representing 48 minutes. Long life and extreme reliability of input switch ing is achieved using reed relays driven by transistors in a matrix arrange ment. Analogue to digital conversion is performed directly on the outputs of the thermocouples which are linearized so that the output is in degrees C rather than thermocouple e.m.f. Readout is on strip printers, a type writer and a tape punch. The operating range of the equipment is from 0¿799°C, the long term overall accuracy (excluding thermocouple variations) being ± 3°C.