About Alarm Rules and Operators

FlowWorks gives you the ability to configure rules to alarms and notifications, so that automatic alerts can be sent to those who must know when data is late arriving from a Site, or when data from one or more Channels fall outside specific bounds. This allows you and your team to respond to an adverse situation in a timely manner.

FlowWorks supports two 'levels' of data-based warnings: Alarms and Notifications. While the setup, triggering and functionality of alarms and notifications are the same,  when an alarm is triggered, the site's icon in Map View will turn red, and e-mail / SMS alerts will say "Alarm"; when a notification is triggered, the site's icon in Map View will turn orange and e-mail / SMS alerts will say "Notification". Thus, you could setup both a notification and an alarm for the same site, such that the notification is used as a 'heads up' that a site could be approaching an alarm condition, while the alarm indicates that a critical condition has been met, and 'immediate attention is required'.

In preparing to setup new alarms and notifications, it is important that you understand how our alarm rules and operators work. In subsequent topics, we discuss how to create new alarms and notifications using these concepts.

About rules

We use rules to define triggers - what FlowWorks' system must evaluate as 'true' for activating an alarm / notification. Once all defined rules in a trigger evaluate as 'true', the Alarm / Notification is activated, and the appropriate 'actions' (alerts) are deployed.

In the simplest case, an alarm or notification trigger has just one rule. FlowWorks' system will continually compare the rule with incoming data. As long as the rule evaluates as 'false', nothing will happen. However, when the rule evaluates as 'true', the user's specified actions will instantly deploy.

For example, let's say we have a channel measuring a sewer's depth level, and we  created a rule stating that an alarm must trigger once  depth exceeds 4-feet. For every new incoming data point, the system will evaluate the data-value against the rule. If the level is at 3.5-feet, the rule will evaluate as 'false' and no message(s) will be sent. However, as soon as a new datapoint exceeds 4-feet, such as 4.2-feet, the system will evaluate the rule as 'true' and the pre-defined alert(s) will be automatically  sent to the recipient(s) specified in the alarm's settings.

For any rule, the data in a channel may be compared to a trigger-value with the following options:

  • The channel’s data is greater-than () a value you assign.
  • The channel’s data is less-than () a value you assign.
  • The channel’s data is equal-to (=)  a value you assign.
  • The channel’s data is greater-than-or-equal-to (=)  a value you assign.
  • The channel’s data is less-than-or-equal-to (=)  a value you assign.
  • The channel’s data is not-equal-to ()  a value you assign.

Each rule you create - comparing a channel’s data to a value - becomes a clause in the overall trigger. You may then combine rules using the operators  AND and OR. The following sections in this article discuss both operators.

About the AND operator

Alarms and notifications can be built of several rules. We can use the AND operator to combine minimally two rules in a trigger, in which all rules must evaluate as 'true' for the trigger to be initiated. FlowWorks' system will always first evaluate each rule in a single trigger, returning either a 'true' or 'false' result. Then the operator(s) that group each of the rules in a single trigger will come into play - if we have a two-rule trigger, and the operator concatenating the two rules is "AND", then both rules must evaluate as 'true' for the trigger to activate.

The alarm will only be processed when new data is available for all channels in the rule at the same time. If data for these channels arrives at different times or with offset intervals, the alarm will not work as expected. Consider using two or more separate rules.

For example, let's say we have a channel measuring a sewer's depth level, and another measuring velocity of flow for the same sewer. We want to deploy an alarm when the sewer's water level rises past 4-feet, AND when velocity slows below 1-foot-per-second; this type of alarm could indicate that downstream from this point, something is blocking flow. We want to ensure that both Rules 1 and  2 evaluate as 'true' for the alarm to be communicated, because the location in which our measurements are taken can experience a level fluctuation - which is not a problem as long as the velocity does not slow to 1 foot-per-second and below. Thus, we  need to create two rules for this trigger, using the AND operator to combine them:

  • Rule 1: Level (Channel)  1.2, AND
  • Rule 2: Velocity (Channel) = 1.5.

The image below depicts how this setup would look in the Alarm Configuration page:

About the OR operator

We can use the OR operator to separate at least two rules in an alarm trigger, in which either rule must evaluate as 'true' for the alarm to be activated.  FlowWorks' system will always first evaluate each rule in a single trigger, returning either a 'true' or 'false' result. Then the operator(s) that group each of the rules in a single trigger will come into play - if we have a two-rule trigger, and the operator concatenating the two rules is "OR", then at least one rule must evaluate as 'true' for the trigger to activate the alarm.

The alarm will only be processed when new data is available for all channels in the rule at the same time. If data for these channels arrives at different times or with offset intervals, the alarm will not work as expected. Consider using two or more separate rules.

For example, let's say we have a few channels measuring a liquid's ability to pass electrical flow (conductivity) in microseimens (uS). We want to deploy an alarm when either channel reads a low conductivity level, as this may indicate a lower-than-desired concentration of dissolved ions in the liquid. For this type of alarm, we don't want to wait until all three of our channels relay a low salinity reading - as soon as at least one rule evaluates as 'true', we want to be notified. Thus, we would need to create three rules for this trigger, using the OR operator to separate them:

  • Rule 1: Conductivity 1 (Channel) < -100, OR
  • Rule 2: Conductivity 2 (Channel) < -1, OR
  • Rule 3: Conductivity 3 (Channel) < -3.

The image below depicts how this setup would look in the Alarm Configuration page:

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