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Show 9 blocks representing (from bottom to top) the first stage of the secondary superheater, the reheater, the second stage of the secondary superheater and the primary superheater. The nLlTlber displayed within this block is the percentage of heat transfer lost due to fouling. A few of the key operating variables are also displayed for quick reference. BOUNDARY DAM UNIT 3 CONVECTION SECTION CLEANLINESS BOILER LORD 149 13- BURNE:R TILT -II 12- [C) S'HEATER TEMP (F") !l9S RtHE:ATER 18- T[MP (F") 18S2 c::Ja.PN rURN EXIT ~ TEMP (F") 2115 IS c:::::sz::l L I GMT !I- ~ ~ EIIIHDWY Figure 7. Screen showing fouling in convection section. Historical Data Analysis System for Engineers On-line or off-line historical plotting of signals has proven very useful for data analysis. Software has been written so that every signal that is collected by the data acquisition systen can be displayed as a historical plot on a colour video display and then printed. Any length of time up to 3 weeks (the limit of storage of the Winchester hard disc), can be plotted on one graph. The ordinate scale of the graph can be set according to the magnitude of the plotted signal. If a nllTlber of simultaneous plots are desired for data analysis the plotting facility is run off-line or on a separate microcoJTl>uter. This more cOJT1)lex plotting program can be run so that all the signals appear on one plot although the practical limit for identification of signals is about six. As well, calculated values such as economizer cleanliness, overall efficiency and furnace exit gas temperature, to name a few, can be plotted. All historical plots presented in this paper have been generated with this plotting program. |