Patent GB-968729-A (GB)
Title: Data acquisition and display apparatus
Inventor: MCAFFER NEIL THOMAS CAMERON
IPC: G21C17/10
Filed: 1962-02-05
Abstract: 968, 729. Measuring temperature electrically. UNITED KINGDOM ATOMIC ENERGY AUTHORITY. Feb. 1, 1963 [Feb. 5, 1962], No. 4316/62. Heading G1N. [Also in Division H4] Signals representative of successive operating conditions at a plurality of points in a plant are derived in sequence by a scanner means and fed to a recording device from which they are supplied to a cathode-ray tube and displayed in a pattern representing the spatial distribution of the points within the plant. The invention is described in connection with monitoring the temperature of a plurality (100) of positions in reactor core and as shown in Fig. 1, comprises a scanner means 11 in the form of a selector switch fed with signals from 100 thermocouples and arranged to supply repeated sequences of rationalised and digitalised output signals proportional to the input signals. The scanner means 11 also pulses a binary counter 12 producing signals representative of the position of the measurement points and these signals together with the scanner output signals are fed to a recording head 13 and recorded on separate peripheral tracks on a magnetic drum 15, basic time signals produced by a pulse generator 10 being also recorded on a further track. The signals are recorded on the drum at the rate of acquisition (about one per second) but in order to produce signals suitable for display the drum rotates at about 3,000 r.p.m. and is synchronised with the acquisition rate such that between successive recordings it completes one revolution plus the distance between successive recordings. All of the signals are then read-off by a continuously responsive replay head 16 and supplied to appropriate units e.g. 21, controlling the horizontal time-base deflection of the display tube 18, a digital-to-analogue counter 17 controlling the vertical deflection via a beam switching device 19 and directly to the latter to control the position of each horizontal line. Additionally a second unmodulated beam is operated by a Y shift control 22 for measuring purposes. Fig. 2a, shows the display produced by this arrangement and comprises four lines 32 each of twenty five signals 31 the heights of which indicate the amount by which the temperature exceeds a reference value determined by the base lines 32 and the positions of which are indicative of the measurement positions in the reactor core. If desired the variation of the temperature of a selected thermocouple may be displayed by continuously recording the signals from such thermocouple during a period of time as determined by a programme unit 14 via a comparator 23 and digital clock 24 and at the end of such period displaying the recorded signals in a pattern similar to that shown in Fig. 2a. By introducing a pulse stretching unit between the digitalto-analogue convertor 17 and the beam switching device 19 the display may be produced as a trace 33 (Fig. 2b) and a pre-set reference trace 35 representing maximum acceptable temperatures may be produced above trace 33 or may be inscribed on the tube. By replacing the elements of "box" 25 (Fig. 1) by elements described with reference to Fig. 3 (not shown) a display in the form of Fig. 2c may be produced in which the positions and brightness of each "dot" represent the positions and temperatures of the various thermocouples but in which no "dots" are produced if the measured temperature is less than a predetermined temperature. The invention may be employed in plants other than Nuclear reactors and may be used for the display of parameters other than temperature.