RAD_CTL Return Air Damper Control - Operation Manual - ELC.E14 - EM1.8D - EM1.8R - EM1.8U

Description

This function block set has the same control logic with "MAD_CTL Mixed Air Damper Control". It is used to control the output of an analog return air damper, which is mainly linked to the output of an outside air damper, i.e., the opening percentage of the return air damper is equal to the subtraction of the outside air damper from 100 %.

This set also has a manually override function. If "Return Air Damper Mode Select" is "0 - MAN (manual)", the output is "Return Air Damper Manual Setpoint". If "Return Air Damper Mode Select" is "1 - AUTO", the output is the automatic logic value of the application.

Function

At any time when "Return Air Damper Mode Select" is "0" (0-MAN/1-AUTO), "Return Air Damper Control" is "Return Air Damper Manual Setpoint".

When "Return Air Damper Mode Select" is "1" (0-MAN/1-AUTO)", "Return Air Damper Control" is equal to the larger value of "Return Air Damper Minimum Setpoint" and the subtraction of the outside air damper from 100 %.

NOTE: The basic logic is the same with mixed air damper control.

Internal logic

Input

Output

Example