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It is common in manufacturing processing plants such as oil and gas refineries, to monitor the temperature trend in furnaces. Example in the refineries, the furnaces tube metal temperature (TMT) monitoring severity increases for dirty services such as crude distillation and coker units. Operation team uses this information to decide either to go for rate cut or feed rate skewing before the TMT reaching mechanical limits to prolong the run length. Upon reaching the limit, the furnace will be taken out-of-service by means of spalling or pigging, and consequently impacts the production rate. Use case: The objective is to highlight the highest and the second highest temperature out of several temperatures in a matrix. Seeq enables users to build a matrix table (or Scorecard prior to R51) to highlight the temperature priority sequence by using a combination of functions and tools including max(), splice(), composite condition and scorecard metrics. Step 1: Start by loading all of the signals we want to include in the matrix into the display. Step 2: Use max() to look for the highest value signal at any time in the formula tool. Type in formula below into formula editor. $t.max($t2).max($t3).max($t4).max($t5).max($t6).max($t7).max($t8) Step 3: Create the second highest signal using splice() and composite condition. To capture the second highest signal, we need first to exclude a signal with the highest temperature at any time and then identify the highest value out of the remaining seven signals. To achieve that, use the highest temperature signal we created in step 2, we then create a condition when a signal reads the highest value, for each eight signals. //Which is the max $if_t1_is_the_max = $t1 == $max $if_t2_is_the_max = $t2 == $max $if_t3_is_the_max = $t3 == $max $if_t4_is_the_max = $t4 == $max $if_t5_is_the_max = $t5 == $max $if_t6_is_the_max = $t6 == $max $if_t7_is_the_max = $t7 == $max $if_t8_is_the_max = $t8 == $max Prior to looking for the max a second time, we must remove or replace the values from each of the signals when they are equal to the max. In this method, we will replace the highest signal values with zero using the splice function during the condition when that signal was the max. With these highest values replaced by zero (or removed), applying the same technique with the max function will yield the value of the second highest signal. //replace the max with 0 $removing_the_max_value = ($t1.splice(0,$if_t1_is_the_max)) .max($t2.splice(0,$if_t2_is_the_max)) .max($t3.splice(0,$if_t3_is_the_max)) .max($t4.splice(0,$if_t4_is_the_max)) .max($t5.splice(0,$if_t5_is_the_max)) .max($t6.splice(0,$if_t6_is_the_max)) .max($t7.splice(0,$if_t7_is_the_max)) .max($t8.splice(0,$if_t8_is_the_max)) .toStep() return $removing_the_max_value Step 4: Create Metric Threshold Limits Subtract the highest signal by a fairly small value using Formula tool in order to use signal as a threshold limit. Repeat the step for second highest limit. $max-0.001 Step 5: Create scorecard metric for each signal. Create scorecards for all 8 signals, as an example we choose value at the end for statistic for daily condition and apply the threshold accordingly. In the table view: Do check this post by Nick. He used different approach to yield the maximum of three signals, and displayed signal string in a matrix table.

Sometimes when looking at an xy plot, it can be helpful to use lines to designate regions of the chart that you'd like users to focus on. In this example, we want to draw a rectangle on the xy plot showing the ideal region of operation, like below. We can do this utilizing Seeq's ability to display formulas overlaid against an xy plot. 1. For this first step, we will create a ~horizontal line on the scatter plot at y=65. This can be achieved using a y=mx+b formula with a very small slope, and a y-intercept of 65. The equation for this "horizontal" line on the xy plot is: 0.00001*$x+65 2. If we want to restrict the line to only the segment making the bottom of our ideal operation box, we can leverage the within function in formula to clip the line at values we specify. Here we add to the original formula to only include values of the line between x=55 and 5=60. (0.00001*$x+65) .within($x>55 and $x<60) 3. Now let's make the left side of the box. A similar concept can be applied to create a vertical line, only a very large positive or negative slope can be used. For our "vertical" line at x=55, we can use the following formula. Note some adjustment of the y-axis scale may be required after this step. (-10000*($x-55)) 4. To clip a line into a line segment by restricting the y values, you can use the max and min functions in Formula, combined with the within function. The following formula is used to achieve the left side boundary on our box: (-10000*($x-55)) .max(65) .min(85) .within($x<55.01 and $x>54.99) The same techniques from steps 1-4 could be used to create the temperature and wet bulb max boundaries. Formula for max temp boundary: (0.00001*$x+85).within($x>55 and $x<60) Formula for max wet bulb boundary: (-10000*($x-60)) .max(65) .min(85) .within($x<60.01 and $x>59.99)

This is a question that came into our Support system today that I thought a number of our users might find interesting. Question - I have a signal that is calculating a number of equipment events and I want to create a scorecard with our total compliance to our procedures showing % Compliance per week / month / year For this example we are going to use the Area A -> Compressor Power example data and create a scorecard judging our compliance with our policy that the compressor has to turn on ever day. Step I - Create a metric that measures if you met your compliance requirement. In this case I will use the Signal from Condition tool to calculate the max compressor power per day. Step 2 - Turn your KPI into a daily 0-100% score in Formula. In our case we are going to say that as long as the max KW per day was greater than 1 kW we are going to consider that a complying event. This step will be different for your calculations be the end result need to be a 1-0 signal with a sample for each compliance period (days in this example). Using the pattern $signal.min(1.tosignal()) will clip the signal at 1. The second part of the formula converts things into 0-100% which will make our scorecards looks nice ($signal*100).setunits("%") Step 3 - Create the scorecard and average all of your 0-100% samples over the reporting period of interest. The reporting period can be created using the Periodic Conditions tool To create different weekly or yearly compliance simply create another Condition in the periodic condition tool and generate another Scorecard. Multiple scorecards can then be combined into a Topic to create a like updating report that looks a bit like the following using Scorecard thresholds to color the values based on your preferences.