# Loss Link Node

## General description

A **loss link** allows for the definition of a fixed proportional loss of flow that goes through this node.  Loss links are often used to represent **potable water treatment works** which incur some process losses.

The Max and Min flow attributes that are defined are applied to the net output after losses. 

The node itself records the net output in its flow attribute (which would be used by any attached recorders).

## Primary Attributes

<table><thead><tr><th width="181.33333333333331">Name</th><th width="342">Description</th><th>Required</th></tr></thead><tbody><tr><td>Allocation Penalty</td><td>The cost per unit flow via the node</td><td>Optional</td></tr><tr><td>Loss factor</td><td>loss_factor : float or Parameter. The proportion of flow that is lost through this node. Must be greater than or equal to zero. This value is either a proportion of gross or net flow depending on the value of <code>loss_factor_type</code>.</td><td>Optional, defaults to 0</td></tr><tr><td>Loss Factor Type</td><td>Either "gross" or "net" (default) to specify whether the loss factor is applied as a proportion of gross or net flow respectively.</td><td>Optional, defaults to "net" </td></tr><tr><td>Max Flow</td><td>The maximum flow constraint on the node</td><td>Optional</td></tr><tr><td>Min Flow</td><td>The minimum flow constraint on the node</td><td>Optional</td></tr></tbody></table>

## Example

<figure><img src="https://2363830371-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FODCd8VK2OOl9jOdp5KFf%2Fuploads%2FUOenCoomXivW5fq5gw1b%2Fimage.png?alt=media&#x26;token=0414898f-8da6-4703-8662-79f349169edc" alt=""><figcaption></figcaption></figure>

In this example 10% of the gross amount of water flowing into the node is lost.