# What is split range control system?

**URL:** <https://forumautomation.com/t/what-is-split-range-control-system/1431>\
**Category:** Industrial Automation\
**Created:** [October 12, 2016, 5:49am UTC](https://forumautomation.com/t/what-is-split-range-control-system/1431 "2016-10-12T05:49:53Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![denizen](https://forumautomation.com/letter_avatar_proxy/v4/letter/d/848f3c/32.png) [@denizen](https://forumautomation.com/u/denizen)\
**Post date:** [October 12, 2016, 5:49am UTC](https://forumautomation.com/t/what-is-split-range-control-system/1431/1 "2016-10-12T05:49:53Z")

</div>

**Split range control system or Duplex Control**

Split range controller has one input and two output.

Split control divides the controller output in to two distinct functions.

Heat/Cool controllers are one example of split control.

 ![Split range Control System Example](https://cdn.forumautomation.com/original/1X/c11e5056883491cdfaccd7d7597de0c892c26336.jpg)The controller senses the value of PV and SP at its input.A proportioning signal is generated in block A. The signal varies from 0 to 100% depending on the size and direction of the process error.

When PV is equal to SP and error is zero,the H/C signal is at 50%.

If the value of the PV decreases below SP,the H/C signal increases proportionally.

If the value of the PV increases above SP,the H/C signal decreases proportionally.

 ![Split Range Control](https://cdn.forumautomation.com/original/1X/f3e31facb1fd2bf6a8dd620ee657f14a06295ca7.JPG)