> For the complete documentation index, see [llms.txt](https://create-deep-seas.gitbook.io/create-deep-seas-wiki/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://create-deep-seas.gitbook.io/create-deep-seas-wiki/deep-seas/diving/pump-controller.md).

# Pump Controller

<img src="https://1371052705-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FV22FKtcNjWW37kUFLLdR%2Fuploads%2Fgit-blob-ec857d948916a68664ce82ec2818b4916cf564e3%2Fpump_controller.png?alt=media" alt="Pump Controller" width="128">

A Create Mechanical Pump that the [Onboard Computer](/create-deep-seas-wiki/deep-seas/diving/onboard-computer.md) can drive. On its own it works like a normal pump. With a computer on the same submarine, the computer decides when it fills, drains or stops.

## Recipe

![Pump Controller recipe](https://1371052705-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FV22FKtcNjWW37kUFLLdR%2Fuploads%2Fgit-blob-bbbf1b641bcbb9c79dbd24cbba32ef66502fd2f3%2Fpump_controller.png?alt=media)

## How to use it

1. Pipe it between the [Ballast Vent](/create-deep-seas-wiki/deep-seas/diving/ballast-vent.md) and the [Ballast Tanks](/create-deep-seas-wiki/deep-seas/diving/ballast-tank.md), like a normal pump.
2. Give it rotation.
3. Place an Onboard Computer anywhere on the same submarine.

That is all. No link, no wire, no wrench. The computer finds every Pump Controller on its ship by itself, and each pump works out which of its ends leads to the tanks, whichever way you placed it.

{% hint style="danger" %}
**Use as few Ballast Tanks as possible, and as many Pump Controllers as you can, on a fast shaft (256 RPM).** Every tank is 8 more buckets to pump in and out. Too many tanks with too few or slow pumps, and the submarine takes ages to dive and to climb back up.
{% endhint %}

## Good to know

* More Pump Controllers or a faster shaft mean faster dives.
* On big submarines each controller pushes harder: it is sized for about 10 tanks, and past that its flow goes up so a huge submarine swings its ballast in about the same time as a small one. The stress cost does not change.
* When the submarine is condemned (120 m deep and 30 m past the limit of its hull), every Pump Controller seizes up, turns red and swells. They stop pumping until you climb 5 m back. See [Cracks, breaches and implosion](/create-deep-seas-wiki/deep-seas/mechanics/cracks-and-implosion.md).

{% hint style="success" %}
**Details to look for**

* Its cog sits slightly forward and spins at its own speed, so you can see which pumps are working.
* When the submarine is condemned, the pump turns red, its casing swells and the cog stops dead.
  {% endhint %}

## Video

{% hint style="info" %}
Video coming soon.
{% endhint %}