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Hello Dear Seeq users, I am trying to find a solution to determine the smallest deviation over a fixed period of time (e.g. 4 hours). Preferably between a minimum and maximum value (e.g. between 150 and 320). Basically, I am trying to find a formula to find the most constant time span of a single signal between 2 values. It would be very nice if someone could help me with this Yours sincerely, Jan

FAQ: I want to create a condition where a trend is within a specific range of slope so as to identify instances where it falls inside and outside these ranges. Is this possible?

I've calculated a scorecard metric that I want to use in a calculation of a condition. While the scorecard metric is visible in trend view, it is not provided as a signal choice in the drop-downs on the tools or in the Seeq formula window. Can my scorecard metric be used in calculations of other signals/conditions?

Background: Sensors or calculated tags that totalize a value over time often need to be reset due to maxing out the range of the sensor or the number of available digits in the calculation database. This can create a saw-tooth signal that resets every time this range maximum is reached. In actuality, the signal is constantly increasing rather than building up to the range max and then stepping down to zero to begin counting back up towards the max. Solution: Use Seeq Formula to convert the saw-tooth signal into a continuously increasing signal bounded in time by some reset period determined by the Subject Matter Expert. 1. In this example we begin with a saw-tooth counter signal that resets every time the sensor reaches its range max of 100. 2. Use Seeq Formula to convert the sawtooth signal into a continuous, increasing signal. Note that in order for Seeq to do this calculation, a bounding condition is required. This can either be a repeating periodic condition, or a condition created using the custom condition tool. This can be done in one step using the following code: //creates a bounding condition for running sum calculation $reset = years() //calculates running delta of signal between each sample, compares to zero to ignore negative running delta values, //calculates the running sum of the running delta signal over the bounding condition $signal .runningDelta() .max(0) .runningAggregate(sum(),$reset) Content verified MAY2024

I've got a signal with drop-outs and I want to filter my signal to only visualize samples with values above a threshold. Is there a quick way to do this in Seeq?

Hi lots, Is there a functionality of "If...then...else" statements in formulars. Or is there at least a workaround? Thanks for your answer in advance!

Hello there, In my worksheet, I used formula function to create a signal used in my boundary. i.e, 0.tosignal(). I found this signal only shows in the worksheet I created, not the others. if there a way to pin this signal? so that i can reuse the signal i have created. Thank you

As a user, I would like to be able to display the name of the maximum signal in an organizer this will help simplify troubleshooting. Is there anyway to do this? This is relatively simple using Formula and the splice() function. The main trick is getting the string value into the scorecard metric. This can be done by creating a scorecard metric with no statistics to create a scorecard that just displays the value of this string. I have shown an example of this below. This functionality is very useful if you want to create a string signal that has more than one value. For example, say that I have three signals. I want to create a scorecard metric that tells me which of these three signals is the largest at any point in time. I will start by creating a signal who's value at any given time is the corresponding name of the signal with the max value. This can be done relatively easy with formula using the max() and splice() functions. Example Formula: $maxValue = $s1.max($s2).max($s3) 'No Max'.splice('Signal1 is Max', $s1 == $maxValue) .splice('Signal2 is Max', $s2 == $maxValue) .splice('Signal3 is Max', $s3 == $maxValue) The following shows the result of the formula. Finally, I'll use Simple Scorecard again to create a metric that displays this Max Signal for use in Organizer Topics. Content Verified DEC2023

Overview Often times two (or more) units that the same products and unit procedures. This is common in continuous processes that are running a specific "grade"; also in batch processes that are manufacturing the same product ID. Since they are identical pieces of equipment or units, the “profiles” of critical process parameters are similar and we want to use profiles from multiple units for our reference profile. In this example we will create a profile from 2 units - the same process can be applied for additional units ad infinitum. Then we will apply this profile to a running batch to look for deviations in near real-time. Step 1: Add Signals and Conditions to Display Add the signals for profiling. Then specify the modes of operation, or unit procedures, using Seeq's Condition logic to create capsules - there are various ways to do this using Seeq's Capsule logic Formula, Value Search, Custom Condition, Composite Condition, etc. Shown below are temperature signals for two units R-401 and R-402, along with their corresponding unit operations. Note that some capsules are overlapping in time, but don't worry, Seeq will handle this just fine. Step 2: View the signals in Capsule Time Here we use the Seeq trending tools to examine the profiles. Capsule Time is a great way to do this. The 'Group' button in the menu can select the appropriate capsules to overlay the signals - and handle those pesky overlapping capsules on the different units. We can filter out additional capsules if we want; but let's use them all in this example. Here are the profiles we’ll use to make our reference profile: Step 3: Build the Reference Profiles The key to building a reference profile with multiple signals and conditions is to use the Formula Tool. The Reference Profile Tool in the Tools Pane provides a nice user experience for a single signal with a single condition - that approach won't work for us here. We will create two unique profiles, upper and lower, but we’ll need 4 formulas so we can repeat the profile over both the R-401 unit procedures and the R-402 unit procedures. We “selected” each capsule in the formula by creating a bunch of capsule groups that just contained a single capsule. This approach works in all cases including overlapped capsules. Here’s the formula for the upper profile, +3 Standard Deviation, repeated over R-401 and we plotted the reference profile in capsule view. Below is the Formula that we used, for easy cutting/pasting. *Pro Tip* - Use the Start and End times from the Capsules Pane to define the capsule() times in the toGroup() function. The times do not have to match the exact times of the capsule - they only need to fully enclose the single capsule. Usually this gives us a little wiggle-room on the times. This formula uses the referenceTable() function to build the profile across the 2 units and 2 signals. We specified each capsule and each corresponding signal in each capsule then added them using addRows() to the referenceTable(). Then we told Seeq which condition to draw the reference profile using repeatOver() along with the statistic to calculate, +3 StdDev, in this case. Important! The referenceTable() function must include Bounded Capsules, i.e. those with specified maxDurations, otherwise you will get an error suggesting to use the removeLongerThan() function. Make sure that the $c401 and $c402 conditions are either bounded or were created with the removeLongerThan() function. $R401_1 = $c401.toGroup(capsule('2019-10-07T05:00-06:00', '2019-10-07T07:00-06:00')) $R401_2 = $c401.toGroup(capsule('2019-10-07T09:00-06:00', '2019-10-07T11:00-06:00')) $R401_3 = $c401.toGroup(capsule('2019-10-07T15:00-06:00', '2019-10-07T16:30-06:00')) $R401_4 = $c401.toGroup(capsule('2019-10-07T16:30-06:00', '2019-10-07T18:00-06:00')) $R401_5 = $c401.toGroup(capsule('2019-10-08T00:00-06:00', '2019-10-08T02:00-06:00')) $R402_1 = $c402.toGroup(capsule('2019-10-07T05:30-06:00', '2019-10-07T07:30-06:00')) $R402_2 = $c402.toGroup(capsule('2019-10-07T11:00-06:00', '2019-10-07T13:30-06:00')) $R402_3 = $c402.toGroup(capsule('2019-10-07T14:00-06:00', '2019-10-07T15:15-06:00')) $R402_4 = $c402.toGroup(capsule('2019-10-07T15:20-06:00', '2019-10-07T16:40-06:00')) $R402_5 = $c402.toGroup(capsule('2019-10-08T00:30-06:00', '2019-10-08T02:30-06:00')) $rt = referenceTable (2min) .addRows ($t401, $R401_1) .addRows ($t401, $R401_2) .addRows ($t401, $R401_3) .addRows ($t401, $R401_4) .addRows ($t401, $R401_5) .addRows($t402, $R402_1) .addRows($t402, $R402_2) .addRows($t402, $R402_3) .addRows($t402, $R402_4) .addRows($t402, $R402_5) .repeatOver($c401 , ReferenceTableStat.StdDev, 3 ) $rt Repeat the above process for the R-401 lower profile. *Pro Tip* - Use the 'Duplicate' functionality by clicking on the 'Item Properties' i-icon in the Details Pane. Then we only need to change the "3" to a "-3" at toward the end of the formula to do a -3 Standard Deviation. Repeat this process 2 more times for the R-402 upper and lower profiles. We only need to change the parameter in the repeatOver() function from $c401 to $c402. Here is everything plotted in Calendar Time as Reference Profiles and then as Boundaries after using the Boundary Tool. And now with Boundaries: Step 4: Apply Boundary to Running Unit Lastly, let's apply this boundary to a currently running mode of operation or batch. Let's focus on unit R-401 at the moment. All that we need to do is add the currently running capsule to the existing 'R-401 Unit Procedure - Product X' Condition. This can be done in a variety of ways using Seeq's Formula functions for modifying conditions. Here I'll simply add a Capsule by drawing it using the Custom Condition tool. Note, the result is a capsule that shows the boundary of the running batch, projected into the future. This same approach can be applied to unit R-402. Seeq is able to handle any arbitrary amount of units, signals, overlapping or not to create your reference/golden profiles.

There are many use cases where the user wants to do an aggregation over a periodic time frame, but only include certain values. For instance, in this example, we aim to calculate the average daily compressor power but only when the compressor is Online. 1. First, use Value Search to identify when the compressor is ON, which in this example is when the compressor power > 0.5 kW. 2. Then, use the 'Within' function in the formula tool to filter the signal to only include samples when the compressor is ON. 3. Create daily condition using either 'Periodic Condition' or 'Formula' Tool. 4. Finally, use 'Signal from Condition' tool to calculate average daily compressor power when it's ON. Content Verified MAY2024

Background: I have a sensor that shows a step change in the amplitude of the signal noise a couple of days prior to instrument failure. It would be useful to be able to identify that step change in the amplitude of the noise so that preventative maintenance can be scheduled rather than running the instrument to failure and causing an unplanned shutdown or production loss event. Solution: Use a combination of Formula and the Value Search tool to identify when this increased signal noise is occurring. Starting signal: 1. Use Seeq Formula and the runningDelta() and Abs() functions to calculate the absolute value of the running delta of the signal of interest. The formula code to achieve this is: //calculates absolute value of running delta of signal $signal .runningDelta() .abs() 2. Use the Value Search tool to identify the periods of time when this absolute value of running delta signal is above some threshold. In this example we use the remove short capsules/gaps functionality to remove capsules and gaps shorter than 1 hour to capture a single event each time the instrument noise increases.

I'm trying to display large values with more significant figures. For instance, annual reporting of large quantities via scorecard only display scientific notation rather than the actual value received within our historian database.I need to be able to display at lease nine significant figures within the score card and be able to view the trend line with the same number of significant figures. Anyone have any thoughts as to how this can be accomplished? Thank you,