Action rate limit

The action rate limit caps how often a single rule action can run inside a rolling time window. It protects recipients from notification floods when an asset flaps or a noisy rule fires repeatedly. Runs over the limit are not sent — they are recorded in the action history as suppressed, so nothing is silently lost.

A limit can be set two ways:

System-wide default — applies to every action that does not define its own limit.
Per-action override — set on an individual action in a rule, overriding the system default.

Out of the box, with nothing configured, actions are limited to 60 runs per hour.

System-wide default

Click the settings icon in the top right of the page and click Settings.
Navigate to Authentication on the left, under System.
Find the Action rate limit section.

Check Enable action rate limit to turn limiting on, then set the maximum number of runs and the time window. The defaults shown — 60 runs per 1 hour — mirror what the system enforces when nothing has been configured. Available windows are minutes, hours, days, and weeks.

Changes save immediately; there is no separate save button.

Unchecking Enable action rate limit turns rate limiting off entirely for every action that does not define its own limit — including the built-in 60-per-hour default.

Per-action override

An individual action can define its own limit, which always wins over the system-wide default.

Go to Rules and open the rule you want to edit.
Expand the Advanced section of the action.
Check Rate Limit.

Set Max runs and the time window. A newly enabled override starts at 10 runs per hour; adjust it to suit the action.

Leaving Rate Limit unchecked on an action means the action falls back to the system-wide default. To exempt a single action from the system default entirely, see the precedence table below.

Which limit applies

Per-action setting	System-wide setting	Result
Rate Limit checked	Any	The action's own limit applies
Not configured	Enabled	The system-wide limit applies
Not configured	Disabled	No limit — the action always runs
Not configured	Never configured	Built-in default of 60 runs per hour applies

How runs are counted

The window is rolling: each time the action is about to run, the system counts how many times that action has already run since now minus the window.
Counting is per action, not per recipient. An action that emails ten people counts as one run, not ten.
Suppressed runs are not counted. A suppression never extends its own block window, so the action resumes as soon as the earlier successful runs age out of the window.
The limit applies to all action types handled by the action emitter — email, SMS, and custom action types alike.

Example

An action limited to 5 runs per hour fires 5 times between 1:00 and 1:10. Any event between 1:10 and 2:00 is suppressed. At 2:01, the 1:00 run has aged out of the window, so the next event sends normally.

Finding suppressed actions

Every suppressed run is written to the action history with a status of suppressed and the response "Message suppressed: action rate limit exceeded". Use this to confirm a limit is doing what you expect, or to spot a limit set too aggressively.

If the rate limit check itself fails for any reason, the action is sent anyway and the error is logged. A missed alert is treated as worse than a duplicate one.

Choosing a limit

Start with the system-wide default and only add per-action overrides where a specific action needs to be tighter or looser.
Critical, low-frequency alerts (equipment failure, safety events) are good candidates for a generous limit or a per-action exemption.
Noisy threshold alerts on flapping sensors benefit from a tight limit — often combined with a grace period, which suppresses the run at the source rather than after the fact.