---
title: "How to use logical rules"
slug: "how-to-use-logical-rules"
description: "Learn how to use logical rules to control your structures"
status: "new"
updated: 2023-07-04T20:12:56Z
published: 2023-07-04T20:12:56Z
canonical: "help.floodmodeller.com/how-to-use-logical-rules"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://help.floodmodeller.com/llms.txt
> Use this file to discover all available pages before exploring further.

# How to use logical rules

Logical rules can be added to certain units to enable their control to be determined by specified situations. This could include:

- [Applying rules to control movement of a sluice or gated weir](/v1/docs/how-to-apply-logical-rules-to-a-sluice-or-gated-weir)
- [Applying rules to operate a pump](/v1/docs/how-to-apply-logical-rules-to-a-pump)
- [Applying rules to transfer flow via an abstraction unit](/v1/docs/how-to-apply-logical-rules-to-an-abstraction-unit)

based on the water level or flow at a reference point, for instance.

To allow for further flexibility, [global variables](/v1/docs/how-to-add-global-variables-within-logical-rules) can be defined, and these can also be controlled by and referenced in logical rules. This enables a user to, for example, create a timer to start when a certain condition is met, and for multiple gates, pumps, and/or abstraction units to then be controlled by this global timer.

Finally, ensuring your rules are being applied as expected is crucial. This can be checked quickly and easily by [visualising rules taking effect](/v1/docs/how-to-visualise-rules-affecting-structures) within time series plots.