Computrac MAX-1000 User's Manual - Arizona Instrument

Some samples contain more than one volatile material, for example nylon resins withlarge amounts of unpolymerized material (Caprolactam). In these cases, the rate willfall to some fixed value when all the moisture is evaporated, but the monomer is stillevaporating. The graphical display available from the FINAL TEST screen is ofgreat help in visualizing these cases. The rate ending criteria, if set above the rate ofmonomer volatilization, may give the best results.To change the rate ending criteria, move the selector bar to END TEST ON RATEand press the key marked “Selct.” The following screen, END TEST ON RATEappears and the “Selct” key becomes the “Edit” key. Press this key, to change thevalue, (or the “Esc” key to leave without making any changes). The cursor willappear on the first digit. Move the selector to the digit to be changed and use the“Incr” or “Decr” keys to change it. Press “Quit” when finished. Press the “Accpt”key to record the new values, or “Cancl” to revert to the previously stored value.Press the “Esc” key to return to the ENDING CRITERIA menu. Press “Esc” asecond time to return to the EDIT TEST screen and press “Esc” a third and fourthtime to return to the top of the MEMRY START menu.! SAMPLE SIZE OPTIONSThis feature enters an optimum sample sizeand the acceptable minimum and maximumsample range. Sample size ranges can beprogrammed from 2 grams to 39 grams.The sample size should be fairly consistentfor all tests on a particular product in orderto get the best standard deviation possible.When the values for the optimum sample Figure 27 SAMPLE SIZE OPTIONSsize and the minimum and maximum rangeare set, an audible "beep" can beprogrammed to indicate when the sample is too small or too large as it is beingloaded.These values are also used in the horizontal weight scale that is displayed whensample is being added. Use the SAMPLE SIZE OPTIONS menu to program thisfeature.To program this information, selectSAMPLE SIZE OPTIONS and press thekey labeled “Selct.” To enter or changean optimum sample size select SAMPLEFigure 28 SAMPLE SIZE31